Control particles for volumetric assessment

Abstract

A biological analyzer's ability to report mean corpuscular volume (MCV) values may be tested using a method which includes providing a control sample, capturing measurements of particles, and reporting a set of MCV values based on the measurements. In support of such a method a sample may be provided which comprises different subsets of control particles which each have their own corresponding size range. These size ranges may be set so that no more than one of the subsets would be occluded by red blood cells (RBCs) that may also be present in the control sample, so that measurements of the remaining subsets may be used in determining the MCV value(s) to be reported.

Description

CONTROL PARTICLES FOR VOLUMETRIC ASSESSMENTCROSS REFERENCE TO RELATED APPLICATIONS

[0001] This is related to, and claims the benefit of, provisional patent application 63 / 651,589, filed in the United States patent office on May 24, 2024 for “Control Particles for Volumetric Assessment,” which application is hereby incorporated by reference in its entirety.BACKGROUND

[0002] Blood cell analysis is a commonly performed medical test for providing an overview of a patient's health status. A blood sample can be drawn from a patient's body and stored in a test tube containing an anticoagulant to prevent clotting. A whole blood sample normally comprises three major classes of blood cells including red blood cells (erythrocytes), white blood cells (leukocytes) and platelets (thrombocytes). Each class can be further divided into subclasses of members. For example, five major types or subclasses of white blood cells (WBCs) have different shapes and functions. White blood cells may include neutrophils, lymphocytes, monocytes, eosinophils, and basophils. There are also subclasses of the red blood cell types. The appearances of particles in a sample may differ according to pathological conditions, cell maturity and other causes. Red blood cell subclasses may include reticulocytes and nucleated red blood cells.

[0003] To evaluate and document whether an analyzer is able to effectively perform its tasks, such as, but not limited to, analysis of blood samples, it may be provided with a control sample having known characteristics, and the results of analysis by the analyzer compared with what would be expected based on the control samples’ known characteristic(s). Control particles can be used to test for various parameters, including counts and cell volumes - when used to assessred blood cell volume, the measurement is commonly referred to as mean corpuscular volume (MCV). One challenge faced when using these types of controls is excessive drift in the MCV measurement, as red blood cells (RBCs) used for MCV measurements tend to change volume (e.g., shrink) over time. To account for this volumetric change over time, refrigeration can be used to preserve the control sample / control particles, however this requires significant cost and attention to prepare and ship these in a refrigerated state, and there is also a limited shelf life. Accordingly, there is a need for improved control technology which can be used to evaluate an analyzer’s ability to make MCV measurements.SUMMARY

[0004] Described herein are manufactures, systems and methods which can be used to evaluate an analyzer’s ability determine MCV values and, in particular, which use multiple different sizes of fixed or synthetic particles to make MCV value determinations while accounting for the risk of being obscured by RBCs in the control sample.

[0005] In some aspects, the disclosed technology may be used to provide a method for testing a biological analyzer. Such a method may include providing a control sample, capturing measurements of particles, and reporting a set of MCV values based on the measurements. In support of such a method a sample may be provided which comprises different subsets of control particles which each have their own corresponding size range. These size ranges may be set so that no more than one of the subsets would be occluded by red blood cells (RBCs) that may also be present in the control sample, so that measurements of the remaining subsets may be used in determining the MCV value(s) to be reported.

[0006] While multiple examples are described herein, still other examples of the described subject matter will become apparent to those skilled in the art from the following detailed description and drawings, which show and describe illustrative examples of disclosed subject matter. Aswill be realized, the disclosed subject matter is capable of modifications in various aspects, all without departing from the spirit and scope of the described subject matter. Accordingly, the drawings and detailed description are to be regarded as illustrative in nature and not restrictive.BRIEF DESCRIPTION OF THE DRAWINGS

[0007] While the specification concludes with claims which particularly point out and distinctly claim the invention, it is believed the present invention will be better understood from the following description of certain examples taken in conjunction with the accompanying drawings, in which like reference numerals identify the same elements and in which:

[0008] FIG. 1 is a schematic illustration, partly in section and not to scale, showing a flowcell based analyzer.

[0009] FIG. 2 schematically depicts a schematic representation of a cellular analysis system.

[0010] FIG. 3 illustrates a transducer module.

[0011] FIGS. 4A-4C provide graphical illustrations of a potential relationship between RBCs and size ranges which may be used for subsets of control particles.

[0012] FIG. 5 illustrates a method which may be used to test a biological analyzer.

[0013] FIG. 6 illustrates acts which may be performed in connection with reporting a set of one or more MCV values(s).

[0014] The drawings are not intended to be limiting in any way, and it is contemplated that various embodiments of the invention may be carried out in a variety of other ways, including those not necessarily depicted in the drawings. The accompanying drawings incorporated in and forming a part of the specification illustrate several aspects of the present invention, andtogether with the description serve to explain the principles of the invention; it being understood, however, that this invention is not limited to the precise arrangements shown.DETAILED DESCRIPTION

[0015] The present disclosure relates to articles of manufacture, methods and analyzers for testing biological analyzers and, in particular, for assessing their ability to measure volumetric values. As described herein, the teachings of this document may be applied in a variety of different manners, and in a variety of different contexts. For example, the disclosed technology may be applied in or with analyzers that take measurements in a variety of manners, such as through imaging, impedance measurements, or other types of measurements. Accordingly, while this disclosure describes various concrete embodiments which may be implemented using aspects of the disclosed technology, those descriptions should be understood as being illustrative only, and should not be treated as limiting on the scope of protection provided by this document or any related document.

[0016] The term “mean corpuscular volume” and MCV may be used herein. The terms refer to a volumetric parameter of a red blood cell, that is a mean or average volume of a red blood cell. More specifically, taking a mean or average of red blood cell volumes for a plurality of red blood cells. Though these terms may be used herein, they are not meant to be overly limiting and should be construed as referring to measurement(s) involving or contributing to mean / average volumetric determination of a red blood cell.

[0017] Turning now to the drawings, FIG. 1 schematically shows an exemplary flow cell 22 for conveying a sample fluid through a viewing zone 23 of a high optical resolution imaging device 24 in a configuration for imaging microscopic particles in a sample flow stream 32 using digital image processing. Flow cell 22 is coupled to a source 25 of sample fluid which may have been subjected to processing, such as contact with a particle contrastagent composition and heating. Flow cell 22 is also coupled to one or more sources 27 of a particle and / or intracellular organelle alignment liquid (PIOAL), such as a clear glycerol solution having a viscosity that is greater than the viscosity of the sample fluid.

[0018] The sample fluid is injected through a flattened opening at a distal end 28 of a sample feed tube 29, and into the interior of the flow cell 22 at a point where the PIOAL flow has been substantially established resulting in a stable and symmetric laminar flow of the PIOAL around / surrounding (e.g., circumferentially in a circular cross-sectional arrangement, or surrounding a plurality of sides of in a non-circular (e.g., rectangular) cross-sectional arrangement) the ribbon-shaped sample stream. The sample and PIOAL streams may be supplied by precision metering pumps that move the PIOAL with the injected sample fluid along a flowpath that narrows substantially. The PIOAL envelopes and compresses the sample fluid in the zone 21 where the flowpath narrows. Hence, the decrease in flowpath thickness at zone 21 can contribute to a geometric focusing of the sample stream 32. The sample fluid ribbon 32 is enveloped and carried along with the PIOAL downstream of the narrowing zone 21, passing in front of, or otherwise through the viewing zone 23 of, the high optical resolution imaging device 24 where images are collected, for example, using a charge coupled device (CCD) 48. In this way, flow imaging is performed where images from the flowing sample stream and the cellular material contained therein are collected. Processor 18 can receive, as input, pixel data from CCD 48. The sample fluid ribbon flows together with the PIOAL to a discharge 33.

[0019] As shown here, the narrowing zone 21 can have a proximal flowpath portion 21a having a proximal thickness PT and a distal flowpath portion 21b having a distal thickness DT, such that distal thickness DT is less than proximal thickness PT. The sample fluid can therefore be injected through the distal end 28 of sample tube 29 at a location that is distal to the proximal portion 21a and proximal to the distal portion 21b. Hence, the sample fluid can enter the PIOAL envelope as the PIOAL stream is compressed by the zone 21. wherein the sample fluidinjection tube has a distal exit port through which sample fluid is injected into flowing sheath fluid, the distal exit port bounded by the decrease in flowpath size of the flow cell.

[0020] The digital high optical resolution imaging device 24 with objective lens 46 is directed along an optical axis that intersects the ribbon-shaped sample stream 32. The relative distance between the objective 46 and the flow cell 33 is variable by operation of a motor drive 54, for resolving and collecting a focused digitized image on a photosensor array. In one example, objective 46 can be thought of as a microscope or a part of a microscope, in that it magnifies an imaging area. In various examples, such relative distance is achieved whereby the motor drive 54 can move the objective relative to the fixed flow cell, the flow cell relative to the fixed objective, or the camera relative to at least one of the fixed objective or fixed flowcell. Additional information regarding the construction and operation of an exemplary flow cell such as shown in FIG. 1 is provided in U.S. Patent 9,322,752, entitled “Flow cell Systems and Methods for Particle Analysis in Blood Samples,” filed on March 17, 2014, the disclosure of which is hereby incorporated by reference in its entirety. Descriptions of approaches which may be used for focusing in an imaging system such as shown in FIG. 1 are provided in Published App. No. 2024 / 0357232 titled “Focus Quality Determination through Multi-Layer Processing,” filed on June 11, 2024, U.S. Patent 9,857,361 titled “Flowcell, Sheath fluid, and Autofocus Systems and Methods for Particle Analysis in Urine Samples”, filed on March 17, 2014, U.S. Patent 10,705,008 titled “Autofocus Systems and Methods for Particle Analysis in Blood Samples”, filed on March 17, 2014, U.S. Patent 10,705,011, titled “Dynamic Focus System and Methods”, filed October 5, 2017, and international application WO2023 / 150064 titled “Measure Image Quality of Blood Cell Images”, filed January 27, 2023, the disclosures of each of which are hereby incorporated by reference in their entirety. Descriptions of approaches which may be used for focusing in an imaging system such as shown in FIG. 1 are provided in Published App. No. 2024 / 0357232 titled “Focus Quality Determination through Multi-Layer Processing,” filed on June 11, 2024, U.S. Patent 9,857,361 titled “Flowcell, Sheath fluid, and Autofocus Systems and Methods for Particle Analysis in Urine Samples”, filed on March 17, 2014, U.S. Patent 10,705,008 titled “Autofocus Systems and Methods forParticle Analysis in Blood Samples”, filed on March 17, 2014, U.S. Patent 10,705,01 1, titled “Dynamic Focus System and Methods”, filed October 5, 2017, and international application W02023 / 150064 titled “Measure Image Quality of Blood Cell Images”, filed January 27, 2023, the disclosures of each of which are hereby incorporated by reference in their entirety.

[0021] In addition to the imaging based systems and modules described herein, in some cases the disclosed technology may be implemented or used in connection with other systems. These may include, for example, impedance systems, fluorescence systems, light scatter systems, VCS systems (integration of volume, conductivity, and scatter together), spectrophotometry systems, or any other suitable systems as would be apparent to one skilled in the art in view of the teachings herein. Such systems may be referred to as alternative systems or “non-imaging”, as those systems may not capture high quality images of microscopic particles. Some nonimaging systems may include systems that utilize a different imaging analysis process (e.g., different than the flow imaging described herein) to obtain data, etc. Non-imaging systems may collect sample fluid information including identical, similar, and / or different parameters compared to the information obtained by imaging systems described above. These nonimaging systems may be helpful in order to obtain certain particle information that may be difficult and / or time consuming to derive from images. For example, the imaging system may not be able to assess volumetric data related to cells, and thus a non-imaging system may be included with the imaging system in order to establish this volumetric data. Additional examples of how multiple types of systems may be integrated are provided in U.S. Patent 9,702,806, titled “Hematology Systems and Methods” and filed March 18, 2014, U.S. Patent 10,429,292, titled “Dynamic Range Extension Systems and Methods for Particle Analysis in Blood Samples” and filed March 17, 2014, and U.S. Patent 9,429,524, titled “Systems and Methods for Imaging Fluid Samples” and filed October 17, 2014, the disclosures of each of which are hereby incorporated by reference in their entirety.

[0022] Referring now to FIG. 2, a schematic representation of a cellular analysis system 200 is shown.In some embodiments, and as shown, system 200 may include a preparation system 210, atransducer module 220, and an analysis system 230. While the system 200 is described herein at a very high level, with reference to the three core system blocks (e.g., 210, 220, and 230), the skilled artisan would readily understand that system 200 includes many other system components such as central control processor(s), display system(s), fluidic system(s), temperature control system(s), user-safety control system(s), and the like. In operation, a fluid sample (e.g., a whole blood sample (WBS)) 240 can be presented to the system 200 for analysis. In some instances, the sample 240 is aspirated into system 200. Exemplary aspiration techniques are known to the skilled artisan. After aspiration, the sample 240 can be delivered to a preparation system 210. Preparation system 210 receives the sample 240 and can perform operations involved with preparing the sample 240 for further measurement and analysis. For example, preparation system 210 may separate the sample 240 into predefined aliquots for presentation to transducer module 220. Preparation system 210 may also include mixing chambers so that appropriate reagents may be added to the aliquots. For example, where an aliquot is to be tested for differentiation of white blood cell subset populations, a lysing reagent (e.g., ERYTHROLYSE, a red blood cell lysing buffer made available by Bio-Rad Laboratories, Inc.) may be added to the aliquot to break up and remove the Red Blood Cells (RBCs). Preparation system 210 may also include temperature control components (not shown) to control the temperature of the reagents and / or mixing chambers. Appropriate temperature controls can improve the consistency of the operations of preparation system 210. As discussed elsewhere herein, sample data such as light scatter data, light absorption data, and / or current data can be obtained (e.g., using a transducer) and processed or used to determine various blood cell status indications of an individual patient.

[0023] In some instances, predefined aliquots can be transferred from preparation system 210 to transducer module 220. As described in further detail below, transducer module 220 may be able to perform direct current (DC) impedance, radiofrequency (RF) conductivity, light transmission, and / or light scatter measurements of cells from the sample 240 passing individually therethrough. Measured DC impedance, RF conductivity, and light propagation (e.g., light transmission, light scatter) parameters can be provided or transmitted to analysissystem 230 for data processing. Tn some instances, analysis system 230 may include computer processing features and / or one or more modules or components which can evaluate the measured parameters, identify and enumerate the blood cellular constituents, and correlate a subset of data characterizing elements of the sample 240 with a White Blood Cell Count (WBC) status of the individual. In some instances, excess biological sample from transducer module 220 can be directed to an external (or alternatively internal) waste system 260.

[0024] In one embodiment transducer module 220 comprises an impedance detector which utilizes impedance, also known as the Coulter principle, to count individual cells as they pass through an aperture (correlating a displacement, and corresponding electrical response to cell size / volume). In one embodiment, the impedance detector is configured to measure one or more of red blood cells, white blood cells, and platelets. In one embodiment, the impedance detector is configured to measure red blood cells and platelets (e.g., configuring a threshold to only count cells in the range of a blood cell and platelet), mean corpuscular volume (average volume of red blood cells), and mean platelet volume (average volume of platelets).

[0025] In one embodiment, as each cell passes through an aperture of an impedance detector, a cell volume associated with each cell is detected (e.g., as a function of impedance or resistance detected, or a function of the conductive volume of fluid displaced by the cell). The individual cell volumes are then aggregated (e.g., via a population distribution) to produce a mean or average number which is reported as MCV. Alternatively, a calculation associated with cell parameters can be used to directly or indirectly derive this number, as would be readily ascertainable by one skilled in the art. This type of mean volume determination, as will be explained below, can be used for particles of interest (e.g., particles that are being tested, such as red blood cells or platelets which are being sized and / or counted) as well as control particles (e.g., red blood cell analogues / controls, or platelet analogues / controls).

[0026] In the context of FIG. 3, which illustrates a transducer module (and references an impedance portion of a transducer module), there are electrodes 334, 336 for performing DC impedancemeasurements of cells passing through an interrogation zone (e g., two tanks separated by an aperture which cells pass through). Signals from electrodes 334, 336 are transmitted to an analysis system 304 to process the data and establish a cell count and other numeric cell parameters (e.g., volumetric data). This data is then output to report 306. Any remaining fluid is discharged to waste 308.

[0027] In one example, the use of solely an impedance detector may have particular utility for red blood cells and platelets, or also counting white blood cells where discrimination between the various types of white blood cells is not needed. This is since it may be difficult to distinguish between various types of white blood cells (e.g., at least neutrophils, lymphocytes, monocytes, eosinophils, basophils) solely through an impedance measurement which would count the white blood cell and assess its size, but would need additional analysis to differentiate the type of white blood cell. By way of example, the impedance detector can be used on one or more of: red blood cell count, platelet count, mean corpuscular volume, mean platelet volume, and / or white blood cell count.

[0028] Whatever type of analyzer may be utilized in a particular case, whether it be an imaging or impedance based analyzer such as described in the context of FIGS. 1-3, or a different type of analyzer (e.g., a fluorescence based analyzer), when testing an analyzer’s performance, a control sample may be used to determine and report a set of MCV values, such as a high MCV value, a low MCV value, and a normal MCV value, thereby confirming the analyzer’s ability to report MCV in patent samples regardless of whether the sizes of corpuscles in those samples were above, below or within a normal range. A control which may be used to determine and report such MCV values may comprise a set of control particles which have a plurality of different sizes, which control particles may be made up of synthetic control particles, or blood cells fixed with a fixative such as glutaraldehyde or a stabilizing agent so that their size would not vary over time and they could be used to provide consistent predictable values when used in MCV reporting. In some cases, to support the determination of MCV values, such a set of control particles may be made up of three different subsets of particles, and each of the particlesin each of those subsets may have a size in a corresponding size range. The control sample may also include a plurality of unfixed RBCs, which may be used for making other types of measurements such as measuring RBC count, and the size ranges for the control particles used to determine MCV may be spaced such that no more than one of the subsets of control particles used for determining MCV would be obscured by (i.e., would overlap with) the range of sizes of the unfixed RBCs. An example of how this may be done is provided below in the context of FIGS. 4A-4C. It should be understood that, while some examples provided in the specification herein may use language regarding fixatives or fixation, the references in those examples to fixatives or fixation could be replaced with references to stabilizers or stabilization, and vice versa - such examples are used illustratively and meant to show conditions whereby certain control cells be designed, processed, or manufactured to retain their morphology without the need for refrigeration (e.g., controls that can be maintained at room temperature). Terminology and explanations for concepts related to stabilization and fixation have been provided herein. Illustratively, references may be made to some of these concepts (e.g., fixatives or fixation agents) however such examples should not be construed as limiting and can extend to broader stabilization concepts to help stabilization of certain control cell types (e.g., without need for refrigeration).

[0029] In some examples, the biological control material requires refrigeration to maintain cell integrity for certain analytical control processes (e.g., control processes that require size such as volumetric information, or morphological related information). In some examples, at least a portion of the biological control material does not require refrigeration because the control procedure relates to a parameter (e.g., count) where in-depth data such as size, volume, or other morphological related information is not needed. Other examples may involve stabilization of the biological control such that refrigeration is not required (e.g., the biological controls can be kept at room temperature).

[0030] Stabilization can involve techniques to keep morphological features of control particles / cells intact for an extended period of time. For example, stabilization of control particles at roomtemperature may be maintained for days, for at least a week or for longer than a week, or for as long as a month, or for a month or longer. Such techniques would utilize one or more stabilization agents during the preparation process to help stabilize the cells. In some examples, stabilization involves utilizing a stabilization agent which comprises nourishing media during the control cell preparation process to help stabilize the cells by expanding the timeframe that degradation of the cells occurs, or other techniques known to one skilled in the art. By example, suitable stabilizing agents can be an aqueous solution including a cell nutrient (e.g., lactose or AMP) and contain one or more of the following: a cell nutrient (e.g., lactose, AMP), a fungicide (e.g., methyl paraben, ethyl paraben, propyl paraben), an antimicrobial (e.g., kanamycin sulfate, neomycin sulfate, sodium penicillin, gentamicin sulfate), a surfactant (e.g., Pluronic F60, Pluronic 25R8, Pluronic F127, Kolliphor P188), a plasma protein (e.g., albumin, lipoproteins, globulins, fibrinogens and mixtures thereof), a buffer (e.g., citrate, phosphate), a metal chelating agent (e.g., citrate, EDTA), an agent to maintain tonicity (potassium chloride, sodium phosphate monobasic, and combinations thereof.

[0031] In some examples, stabilization utilizes a fixation process and a fixative agent, wherein cells are exposed to a fixative agent (e.g., an aldehyde, such as glutaraldehyde, formaldehyde, paraformaldehyde, and combinations thereof) which chemically cross-links the cell membrane to stabilize it. Additional information on stabilization and stabilization agents can be found in, for example: US7393688, US4213876, US4299726, US6569682, US5320964 and US4358394 - the contents of which are hereby incorporated by reference in their entirety.

[0032] Exposing red blood cells to a fixative fixes the cell sizes (or to a stabilizer / stabilization agent stabilizes the cell sizes), for example such that they will not need refrigeration to preserve their sizes. Therefore, having a fixed cell size for a control used for mean control volume (MCV) allows for known sizes to test for this parameter. A control used for other parameters (e.g., red blood cell count) can avoid utilizing a fixative or refrigeration; in this case cell sizes changing over time will not affect the control parameter since the control parameter is a count instead of size (e.g., the cell will still be counted regardless if the cell size expands or shrinks). Therefore,in some examples a control sample can utilize multiple populations or multiple cell types - for instance, a MCV control of fixed sizes (e.g., these cells being exposed to a fixative), and a control for other parameters (e.g., a red blood cell count control) which is not fixed and is kept at room temperature and therefore allowed to have its shape or size change over time. The control sample would utilize a certain cell type (e.g., red blood cells) where a first population or group of cells has fixed sizes (e.g., those used for MCV control) and a second population or group of cells is not fixed sizes (e.g., those used for count control).

[0033] The overall control sample can comprise various control cell types, for instance, red blood cells (e.g., of those the multiple population fixed and un-fixed types), white blood cells, and platelets to control for parameters (e.g., count) relating to these various cell types. In this way, the red blood cell control particles are part of a larger composition set of various other control particles (e.g., white blood cells and platelets).

[0034] Turning now to FIGS. 4A-4C, those figures provide graphical illustrations of potential relationships between RBCs and size ranges which may be used for subsets of control particles in some implementations. FIG. 4A illustrates a scenario in which RBCs in a control sample are in a normal size range of 80-100 femtoliters (e.g., if the RBCs have not experienced a drift in their volumes). In this scenario, a first subset of control particles has volumes between 55 and 65 femtoliters, and is not obscured by (i.e., does not overlap with) the RBCs. A second subset of control particles has volumes between 85 and 95 femtoliters, and is obscured by the RBCs. That is, the number of RBCs is so much larger than the number of control particles in the second subset that volume signals from the second subset of control particles may be lost in the signals generated by measurements of the RBCs. Finally, in the scenario of FIG. 4A, a third subset of control particles has volumes between 115 and 125 femtoliters, and is not obscured by the RBCs included in the control sample.

[0035] FIGS. 4B and 4C are similar to FIG. 4A, except that FIGS. 4B and 4C demonstrate potential impacts of RBC volume changes. Specifically, in FIG. 4B, the RBCs have expanded, and sohave volumes between 100 and 120 femtoliters, thereby partially obscuring the third subset, which is made up of fixed cells or synthetic particles having volumes between 115 and 125 femtoliters. In FIG. 4C, the RBCs have contracted, and so have volumes between 60 and 80 femtoliters, thereby partially obscuring the first subset, which is made up of fixed cells or synthetic particles having volumes between 55 and 65 femtoliters. In each case, regardless of the drift in the volume of the RBCs, only one subset of the differently sized control particles is obscured thereby allowing the remaining subsets to be used for determining and reporting one or more MCV value(s).

[0036] It should be understood that FIGS. 4A-4C are illustrative only, and that other size ranges for subsets of control particles used to determine MCV, as well as other relationships between those size ranges and the sizes of unfixed RBCs in a control sample may also be used in some cases. For example, while FIGS. 4A-4C illustrated the subsets of control particles which would be used to determine MCV as having size ranges which are smaller than the size range for the unfixed RBCs, it is possible that the subsets of control particles may have size ranges which are similar to, or greater than, the range of sizes for RBCs (e.g., the differences between the minimum and maximum sizes of particles in the subsets may be 20 femtoliters or more, rather than 10 femtoliters as discussed in the context of FIGS. 4A-4C). Similarly, in some cases the distances separating the size ranges of the subsets of control particles used to determine MCV may be greater than the expected size range of the unfixed RBCs (e.g., the subsets of control particles may be separated from each other by more than 20 femtoliters). It is also possible that the size ranges of the subsets of control particles and / or the separation between those size ranges may not be the same for all subsets (e.g., the distance between the range of sizes for the subset with the lowest MCV and the range of sizes for the subset with the second lowest MCV be less than the distance between the range of sizes for the subset with the second highest MCV and the subset with the highest MCV). Other variations (e.g., having different amounts of control particles in the different subsets) are also possible, and could be implemented without undue experimentation based on this disclosure. Accordingly, the examples given in thecontext of FIGS. 4A-4C should be understood as being illustrative only, and should not be treated as limiting.

[0037] When a control sample comprises multiple subsets of particles associated with different size ranges such as described in the context of FIGS. 4A-4C, the disclosed technology may be used to provide appropriate MCV values for high, low and normal MCV value controls using measurements from particles in the non-occluded subsets. For example, in a case where there are three subsets of control particles equations such as set for the below as equations 1-4 can be used in determining the reported MCV value(s).LVi = VAI * (Vl+V2) / 2 / VIEquation 1HVi = VA3 * (V2+V3) / 2 / V3Equation 2LV2= VA2 * (Vl+V2) / 2 / V2Equation 3HV2= VA2 * (V2+V3) / 2 / V2Equation 4In the above equations, VAI, VA2 and VA3 are actual MCV values based on measurements of particles in, respectively, the first, second and third subsets of control particles. VI, V2 and V3 are known MCV values for, respectively, the first, second and third subsets of control particles (e g., values defined by the manufacturer of the control sample). LVi is a normalized low value which can be used in cases where the first subset of control particles is not occluded, LV2is a normalized low value which can be used in cases where the first subset of control particles is occluded, HVi is a normalized high value which can be used in cases where the third subset of control particles is not occluded, and HV2is a normalized high value which can be used in cases where the third subset of control particles is occluded. Based on those equations, appropriate normalized values can be calculated regardless of which subset ofcontrol particles is occluded, and those values can then be combined to provide an appropriate MCV value for high, normal and low MCV controls.

[0038] To illustrate how controls and calculations such as described above in the context of FIGS. 4A-4C and equations 1-4 may be applied, FIG. 5 illustrates a method which may be used to test a biological analyzer. As shown in that figure, testing a biological analyzer may include providing 501 a control sample, such as a control sample which comprises a set of control particles having a plurality of different sizes as described. This may be done, for example, loading a control sample into the analyzer and initiating a control run in which the control sample would be processed to provide data that could be used to assess the analyzer’s performance. After the control sample has been provided, the method may continue with capturing 502 measurements of particles from the set of control particles. This may be done, for example, using systems as described in the context of FIGS. 1-3, such as by capturing volume measurements based on impedance. Finally, with the measurements captured 502, the method may conclude with reporting 503 a set of MCV values based on those measurements. Exemplary acts which may be performed in this reporting are depicted in FIG. 6, discussed below.

[0039] As shown in FIG. 6, a first step which may be performed for reporting 503 MCV values may be determining 601 a subset of the control particles in the control samples which is occluded. To illustrate how this may be done, consider a case such as discussed in the context of FIGS. 4A-4C, where a control sample comprises three subsets of control particles whose sizes are spaced such that only one subset would overlap with a plurality of unfixed RBCs that are also present in the control sample. This could be done, for example, by the analyzer comparing the number of particles identified in the size ranges for each of the subsets of control particles, and, if any of the subsets of control particles had more particles in its size range than could be accounted for by the control particles themselves, identifying that subset as being occluded by RBCs. Once the occluded subset had been determined, actual MCV values could be determined 602 for the remaining subsets, such as by averaging the volume measurements of particles inthe size ranges corresponding to those remaining subsets. These actual MCV values could then be used, along with known MCV values for the various subsets, to determine 603 604 normalized low and high values, such as by using calculations as described previously in the context of equations 1-4. Finally, those normalized low and high values could be used to determine 605 appropriate MCV values, which could ultimately then be reported 503 to a user.

[0040] Note, descriptions for fixatives, fixation agents, stabilization, and stabilization agents have been included herein. Illustratively, references may be made to some of these concepts (e.g., fixatives or fixation agents) however such examples should not be construed as limiting and can extend to broader stabilization concepts to help stabilization of certain control cell types (e.g., without need for refrigeration).

[0041] Other applications than simply methods as described in the context of FIGS. 5 and 6 are also possible for the disclosed technology. Accordingly, to further illustrate potential implementations and embodiments of the disclosed technology, exemplary samples, systems and methods which could be practiced based on this disclosure are provided below.

[0042] Example 1

[0043] A mean corpuscular value control sample material comprising a set of control particles having a plurality of different sizes.

[0044] Example 2

[0045] The control sample material of example 1, wherein the set of control particles having the plurality of different sizes comprises blood derived cells which have the plurality of different sizes and whose sizes are stabilized with a stabilization agent.

[0046] Example 3

[0047] The control sample material of example 2, wherein the stabilizing agent is a fixing agent.

[0048] Example 4

[0049] The control sample material of any of examples 2-3, wherein the fixing agent is glutaraldehyde.

[0050] Example 5

[0051] The control sample material of any of examples 1-4, wherein the set of control particles having the plurality of different sizes comprises a set of synthetic control particles which have the plurality of different sizes.

[0052] Example 6

[0053] The control sample material of any of examples 1-5, wherein: the plurality of different sizes comprises a first size range, a second size range and a third size range; the set of control particles having the plurality of different sizes comprises: a first subset of control particles, wherein each control particle in the first subset of control particles has a size in the first size range; a second subset of control particles, wherein each control particle in the second subset of control particles has a size in the second size range; and a third subset of control particles, wherein the third subset of control particles has a size in the third size range.

[0054] Example 7

[0055] The control sample material of example 6, wherein the first size range is between 55 and 60 femtoliters, the second size range is between 85 and 95 femtoliters, and the third size range is between 115 and 125 femtoliters.

[0056] Example 8

[0057] The control sample material of any of examples 6-7, wherein: the control sample comprises a plurality of unstabilized red blood cells (RBCs), having a range of sizes in within a RBC range dispersion between a size of a smallest unstabilized RBC and a size of a largest unstabilized RBC; a maximum of the first size range of the first subset of control particles is less than aminimum of the second size range of the second subset of control particles by at least the RBC range dispersion; and a maximum of the second size range of the second subset of control particles is less than a minimum of the third size range of the third subset of control particles by at least the RBC range dispersion.

[0058] Example 9

[0059] The control sample material of example 8, wherein the RBC range dispersion is between 80 and 100 femtoliters.

[0060] Example 10

[0061] The control sample material of any of examples 1-9, comprising a set of control particles for a red blood cell count.

[0062] Example 11

[0063] The control sample material of example 10, wherein the set of control particles for the red blood cell count are unfixed.

[0064] Example 12

[0065] A method of testing a biological analyzer, comprising: capturing measurements of particles from the set of control particles of the control sample material of any of examples 1-11; and reporting a set of mean corpuscular volume (MCV) values based on the measurements of particles from the set of control particles.

[0066] Example 13

[0067] A system comprising: one or more processors; and a non-transitory computer readable medium having stored thereon instructions for testing a biological analyzer using the control sample material of any of examples 1-11 when executed using the one or more processors.

[0068] Example 14

[0069] A non-transitory computer readable medium having stored thereon instructions for, when executed using one or more processors, testing a biological analyzer using the control sample material of any of examples 1-11.

[0070] Example 15

[0071] A method of testing a biological analyzer, comprising: providing a control sample, wherein the control sample comprises a set of control particles having a plurality of different sizes; capturing measurements of particles from the set of control particles; and reporting a set of mean corpuscular volume (MCV) values based on the measurements of particles from the set of control particles.

[0072] Example 16

[0073] The method of example 15, wherein the set of control particles having the plurality of different sizes comprises blood derived cells which have the plurality of different sizes and whose sizes are stabilized with a stabilization agent.

[0074] Example 17

[0075] The method of example 16, wherein the stabilization agent is a fixing agent which cross links the cell membranes.

[0076] Example 18

[0077] The method of any of examples 16-17, wherein the stabilization agent is glutaraldehyde.

[0078] Example 19

[0079] The method of example 16, wherein: the the set of control particles comprises a set of control particles which are unfixed; and the method comprises reporting a red blood cell count based on measurements of the set of control particles which are unfixed

[0080] Example 20

[0081] The method of any of examples 15-119, wherein the set of control particles having the plurality of different sizes comprises a set of synthetic control particles which have the plurality of different sizes.

[0082] Example 21

[0083] The method of any of examples 15-20, wherein: the plurality of different sizes comprises a first size range, a second size range and a third size range; the set of control particles having the plurality of different sizes comprises a set of subsets of control particles comprising: a first subset of control particles, wherein each control particle in the first subset of control particles has a size in the first size range; a second subset of control particles, wherein each control particle in the second subset of control particles has a size in the second size range; and a third subset of control particles, wherein the third subset of control particles has a size in the third size range.

[0084] Example 22

[0085] The method of example 21, wherein the first size range is between 55 and 60 femtoliters, the second size range is between 85 and 95 femtoliters, and the third size range is between 115 and 125 femtoliters.

[0086] Example 23

[0087] The method of any of examples 21-22, wherein: the control sample comprises a plurality of unstabilized red blood cells (RBCs), having a range of sizes within a RBC range dispersion between a size of a smallest unstabilized RBC and a size of a largest unstabilized RBC; amaximum of the first size range of the first subset of control particles is less than a minimum of the second size range of the second subset of control particles by at least the RBC range dispersion; and a maximum of the second size range of the second subset of control particles is less than a minimum of the third size range of the third subset of control particles by at least the RBC range dispersion.

[0088] Example 24

[0089] The method of example 23, wherein the RBC range dispersion is between 80 and 100 femtoliters.

[0090] Example 25

[0091] The method of any of examples 23-24, wherein the method comprises: determining a subset of control particles which is occluded by the plurality of unstabilized RBCs wherein the subset of control particles which is occluded by the plurality of unstabilized RBCs is the first subset of control particles, the second subset of control particles, or the third subset of control particles; and determining, for each subset of control particles from the set of subsets of control particles, except for the subset of control particles which is occluded by the plurality of unstabilized RBCs, an actual MCV value based on measurements of particles in that subset captured by the analyzer.

[0092] Example 26

[0093] The method of example 25, wherein reporting the set of MCV values comprises: determining a normalized low value based on: a first known MCV value and a second known MCV value, wherein the first known MCV value is a known MCV value corresponding to the first subset of control particles, and wherein the second known MCV value is a known MCV value corresponding to the second subset of control particles; and a low normalization ratio, wherein the low normalization ratio is a ratio of the actual MCV value for the first subset of control particles to the first known MCV value when the first subset of control particles is not occludedby the plurality of unstabilized RBCs, and wherein the low normalization ratio is a ratio of the actual MCV value for the second subset of control particles to the second known MCV value when the first subset of control particles is occluded by the plurality of unstabilized RBCs; and determining a normalized high value based on: the second known MCV value and a third known MCV value, wherein the third known MCV value is a known MCV value corresponding to the third subset of control particles; and a high normalization ratio, wherein the high normalization ratio is a ratio of the actual MCV value for the third subset of control particles to the third known MCV value when the third subset of control particles is not occluded by the plurality of unstabilized RBCs, and wherein the high normalization ratio is the ratio of the actual MCV value for the second subset of control particles to the second known MCV value when the third subset of control particles is occluded by the plurality of unstabilized RBCs; and determining the set of MCV values based on the high normalization value and the low normalization value.

[0094] Example 27

[0095] The method of any of examples 25-26, wherein the method comprises reporting a red blood cell (RBC) count based on measurements of the plurality of unstabilized RBCs.

[0096] Example 28

[0097] The method of any of examples 23-27, wherein the first subset of control particles, the second subset of control particles, and the third subset of control particles each comprise synthetic control particles.

[0098] Example 29

[0099] The method of any of examples 23-28, wherein the first subset of control particles, the second subset of control particles, and the third subset of control particles each comprise blood derived cells which have the plurality of different sizes and whose sizes are stabilized with a stabilizing agent.

[0100] Example 30

[0101] The method of example 29, wherein the stabilization agent is a fixing agent which cross links the cell membrane.

[0102] Example 31

[0103] The method of any of examples 29-30, wherein the stabilization agent is glutaraldehyde.

[0104] Example 32

[0105] A system comprising: one or more processors; a non-transitory computer readable medium having stored thereon instructions for performing the method of any of examples 15- 31 when executed using the one or more processors.

[0106] Example 33

[0107] A non-transitory computer readable medium having stored therein instructions for performing the method of any of examples 15-31.

[0108] Example 34

[0109] A system comprising a processor and a non-transitory computer readable medium storing instructions operable to, when executed by the processor, perform a set of acts comprising: receiving a control sample, wherein the control sample comprises a set of control particles having a plurality of different sizes; capturing measurements of particles from the set of control particles; and reporting a set of mean corpuscular volume (MCV) values based on the measurements of particles from the set of control particles.

[0110] Example 35

[0111] The system of example 34, wherein the set of control particles having the plurality of different sizes comprises blood derived cells which have the plurality of different sizes and whose sizes are stabilized with a stabilizing agent.

[0112] Example 36

[0113] The system of example 35, wherein the stabilization agent is a fixing agent which cross links the cell membrane.

[0114] Example 37

[0115] The system of any of examples 35-36, wherein the stabilization agent is glutaraldehyde.

[0116] Example 38

[0117] The system of any of examples 35-37, wherein: the set of control particles comprises a set of control particles which are unfixed; and the set of acts comprises reporting a red blood cell count based on measurements of the set of control particles which are unfixed.

[0118] Example 39

[0119] The system of any of examples 34-38, wherein the set of control particles having the plurality of different sizes comprises a set of synthetic control particles which have the plurality of different sizes.

[0120] Example 40

[0121] The system of examples 34-39, wherein: the plurality of different sizes comprises a first size range, a second size range and a third size range; the set of control particles having the plurality of different sizes comprises a set of subsets of control particles comprising: a first subset of control particles, wherein each control particle in the first subset of control particleshas a size in the first size range; a second subset of control particles, wherein each control particle in the second subset of control particles has a size in the second size range; and a third subset of control particles, wherein the third subset of control particles has a size in the third size range.

[0122] Example 41

[0123] The system of example 40, wherein the first size range is between 55 and 60 femtoliters, the second size range is between 85 and 95 femtoliters, and the third size range is between 115 and 125 femtoliters.

[0124] Example 42

[0125] The system of any of examples 40-41, wherein: the control sample comprises a plurality of unstabilized red blood cells (RBCs), having a range of sizes within a RBC range dispersion between a size of a smallest unstabilized RBC and a size of a largest unstabilized RBC; a maximum of the first size range of the first subset of control particles is less than a minimum of the second size range of the second subset of control particles by at least the RBC range dispersion; and a maximum of the second size range of the second subset of control particles is less than a minimum of the third size range of the third subset of control particles by at least the RBC range dispersion.

[0126] Example 43

[0127] The system of example 42, wherein the RBC range dispersion is between 80 and100 femtoliters.

[0128] Example 44

[0129] The system of any of examples 42-43, wherein the set of acts comprises: determining a subset of control particles which is occluded by the plurality of unstabilized RBCs wherein the subset of control particles which is occluded by the plurality of unstabilizedRBCs is the first subset of control particles, the second subset of control particles, or the third subset of control particles; and determining, for each subset of control particles from the set of subsets of control particles, except for the subset of control particles which is occluded by the plurality of unstabilized RBCs, an actual MCV value based on measurements of particles in that subset captured by the analyzer.

[0130] Example 45

[0131] The system of example 44, wherein reporting the set of MCV values comprises: determining a normalized low value based on: a first known MCV value and a second known MCV value, wherein the first known MCV value is a known MCV value corresponding to the first subset of control particles, and wherein the second known MCV value is a known MCV value corresponding to the second subset of control particles; and a low normalization ratio, wherein the low normalization ratio is a ratio of the actual MCV value for the first subset of control particles to the first known MCV value when the first subset of control particles is not occluded by the plurality of unstabilized RBCs, and wherein the low normalization ratio is a ratio of the actual MCV value for the second subset of control particles to the second known MCV value when the first subset of control particles is occluded by the plurality of unstabilized RBCs; and determining a normalized high value based on: the second known MCV value and a third known MCV value, wherein the third known MCV value is a known MCV value corresponding to the third subset of control particles; and a high normalization ratio, wherein the high normalization ratio is a ratio of the actual MCV value for the third subset of control particles to the third known MCV value when the third subset of control particles is not occluded by the plurality of unstabilized RBCs, and wherein the high normalization ratio is the ratio of the actual MCV value for the second subset of control particles to the second known MCV value when the third subset of control particles is occluded by the plurality of unstabilized RBCs; and determining the set of MCV values based on the high normalization value and the low normalization value.

[0132] Example 46

[0133] The system of any of examples 41-45, wherein the first subset of control particles, the second subset of control particles, and the third subset of control particles each comprise synthetic control particles.

[0134] Example 47

[0135] The system of any of examples 41-46, wherein the first subset of control particles, the second subset of control particles, and the third subset of control particles each comprise blood derived cells which have the plurality of different sizes and whose sizes are stabilized with a stabilizing agent.

[0136] Example 48

[0137] A non-transitory computer readable medium having stored thereon a set of instructions for performing the set of acts the instructions the non-transitory computer readable medium of any of examples 34-47 are to perform when executed.

[0138] Example 49

[0139] A method comprising performing the set of acts the instructions stored on the non- transitory computer readable medium of any of examples 34-47 are to perform when executed.

[0140] It should be understood that, in the above examples and the claims, a statement that something is “based on” something else should be understood to mean that it is determined at least in part by the thing that it is indicated as being based on. To indicate that something must be completely determined based on something else, it is described as being “based EXCLUSIVELY on” whatever it must be completely determined by.

[0141] It should be understood that a statement that “one or more” or “at least one” of a type of item have a characteristic indicates that the items in the indicated group collectivelyhave the characteristic. To indicate that each item in a group has a characteristic, the phrase “each of’ will be used with the group identifier (e.g., “one or more” or “at least one”).

[0142] It should be understood that, in the claims, “set” should be understood as referring to one or more thing of similar nature, design or function.

[0143] It should be understood that any of the examples described herein may include various other features in addition to or in lieu of those described above. By way of example only, any of the examples described herein may also include one or more of the various features disclosed in any of the various references that are incorporated by reference herein.

[0144] It should be understood that any one or more of the teachings, expressions, embodiments, examples, etc. described herein may be combined with any one or more of the other teachings, expressions, embodiments, examples, etc. that are described herein. The above-described teachings, expressions, embodiments, examples, etc. should therefore not be viewed in isolation relative to each other. Various suitable ways in which the teachings herein may be combined will be readily apparent to those of ordinary skill in the art in view of the teachings herein. Such modifications and variations are intended to be included within the scope of the claims.

[0145] It should be appreciated that any patent, publication, or other disclosure material, in whole or in part, that is said to be incorporated by reference herein is incorporated herein only to the extent that the incorporated material does not conflict with existing definitions, statements, or other disclosure material set forth in this disclosure. As such, and to the extent necessary, the disclosure as explicitly set forth herein supersedes any conflicting material incorporated herein by reference. Any material, or portion thereof, that is said to be incorporated by reference herein, but which conflicts with existing definitions, statements, or other disclosure material set forth herein will only be incorporated to the extent that no conflict arises between that incorporated material and the existing disclosure material.

[0146] Having shown and described various versions of the present invention, further adaptations of the methods and systems described herein may be accomplished by appropriate modifications by one of ordinary skill in the art without departing from the scope of the present invention. Several of such potential modifications have been mentioned, and others will be apparent to those skilled in the art. For instance, the examples, versions, geometries, materials, dimensions, ratios, steps, and the like discussed above are illustrative and are not required. Accordingly, the scope of the present invention should be considered in terms of the following claims and is understood not to be limited to the details of structure and operation shown and described in the specification and drawings.

Claims

CLAIMS1. A control sample material comprising a set of control particles for a mean corpuscular volume having a plurality of different sizes.

2. The control sample material of claim 1, wherein the set of control particles having the plurality of different sizes comprises blood derived cells which have the plurality of different sizes and whose sizes are stabilized with a stabilization agent.

3. The control sample material of claim 2, wherein the stabilization agent is a fixing agent which cross-links the cell membrane.

4. The control sample material of any of claims 2 or 3, wherein the stabilization agent is glutaraldehyde.

5. The control sample material of any of claims 1 -4, wherein the set of control particles having the plurality of different sizes comprises a set of synthetic control particles which have the plurality of different sizes.

6. The control sample material of any of claims 1-5, wherein: the plurality of different sizes comprises a first size range, a second size range and a third size range; the set of control particles having the plurality of different sizes comprises: a first subset of control particles, wherein each control particle in the first subset of control particles has a size in the first size range; a second subset of control particles, wherein each control particle in the second subset of control particles has a size in the second size range; anda third subset of control particles, wherein the third subset of control particles has a size in the third size range.

7. The control sample material of claim 6, wherein the first size range is between 55 and 60 femtoliters, the second size range is between 85 and 95 femtoliters, and the third size range is between 115 and 125 femtoliters.

8. The control sample material of any of claims 6-7, wherein: the control sample comprises a plurality of unstabilized red blood cells (RBCs), having a range of sizes in within a RBC range dispersion between a size of a smallest unstabilized RBC and a size of a largest unstabilized RBC; a maximum of the first size range of the first subset of control particles is less than a minimum of the second size range of the second subset of control particles by at least the RBC range dispersion; and a maximum of the second size range of the second subset of control particles is less than a minimum of the third size range of the third subset of control particles by at least the RBC range dispersion.

9. The control sample material of claim 8, wherein the RBC range dispersion is between 80 and 100 femtoliters.

10. The control sample material of any of claims 1-9, comprising a set of control particles for a red blood cell count.

11. The control sample material of claim 10, wherein the set of control particles for the red blood cell count are unfixed.

12. A method of testing a biological analyzer, comprising:capturing measurements of particles from the set of control particles of the control sample material of any of claims 1-11; and reporting a set of mean corpuscular volume (MCV) values based on the measurements of particles from the set of control particles.

13. A system comprising: one or more processors; and a non-transitory computer readable medium having stored thereon instructions for testing a biological analyzer using the control sample material of any of claims 1-11 when executed using the one or more processors.

14. A non-transitory computer readable medium having stored thereon instructions for, when executed using one or more processors, testing a biological analyzer using the control sample material of any of claims 1-11.

15. A method of testing a biological analyzer, comprising: providing a control sample, wherein the control sample comprises a set of control particles having a plurality of different sizes; capturing measurements of particles from the set of control particles; and reporting a set of mean corpuscular volume (MCV) values based on the measurements of particles from the set of control particles.

16. The method of claim 15, wherein the set of control particles having the plurality of different sizes comprises blood derived cells which have the plurality of different sizes and whose sizes are stabilized with a stabilization agent.

17. The method of claim 16, wherein the stabilization agent is a fixing agent which cross links the cell membranes.

18. The method of any of claims 16-17, wherein the stabilization agent is glutaraldehyde.

19. The method of claim 16, wherein: the set of control particles comprises a set of control particles which are unfixed; and the method comprises reporting a red blood cell count based on measurements of the set of control particles which are unfixed.

20. The method of any of claims 15-19, wherein the set of control particles having the plurality of different sizes comprises a set of synthetic control particles which have the plurality of different sizes.

21. The method of any of claims 15-20, wherein: the plurality of different sizes comprises a first size range, a second size range and a third size range; the set of control particles having the plurality of different sizes comprises a set of subsets of control particles comprising: a first subset of control particles, wherein each control particle in the first subset of control particles has a size in the first size range; a second subset of control particles, wherein each control particle in the second subset of control particles has a size in the second size range; and a third subset of control particles, wherein the third subset of control particles has a size in the third size range.

22. The method of claim 21, wherein the first size range is between 55 and 60 femtoliters, the second size range is between 85 and 95 femtoliters, and the third size range is between 115 and 125 femtoliters.

23. The method of any of claims 21-22, wherein: the control sample comprises a plurality of unstabilized red blood cells (RBCs), having a range of sizes within a RBC range dispersion between a size of a smallest unstabilized RBC and a size of a largest unstabilized RBC; a maximum of the first size range of the first subset of control particles is less than a minimum of the second size range of the second subset of control particles by at least the RBC range dispersion; and a maximum of the second size range of the second subset of control particles is less than a minimum of the third size range of the third subset of control particles by at least the RBC range dispersion.

24. The method of claim 23, wherein the RBC range dispersion is between 80 and 100 femtoliters.

25. The method of any of claims 23-24, wherein the method comprises: determining a subset of control particles which is occluded by the plurality of unstabilized RBCs wherein the subset of control particles which is occluded by the plurality of unstabilized RBCs is the first subset of control particles, the second subset of control particles, or the third subset of control particles; and determining, for each subset of control particles from the set of subsets of control particles, except for the subset of control particles which is occluded by the plurality of unstabilized RBCs, an actual MCV value based on measurements of particles in that subset captured by the analyzer.

26. The method of claim 25, wherein reporting the set of MCV values comprises: determining a normalized low value based on: a first known MCV value and a second known MCV value, wherein the first known MCV value is a known MCV value corresponding to the first subset of control particles,and wherein the second known MCV value is a known MCV value corresponding to the second subset of control particles; and a low normalization ratio, wherein the low normalization ratio is a ratio of the actual MCV value for the first subset of control particles to the first known MCV value when the first subset of control particles is not occluded by the plurality of unstabilized RBCs, and wherein the low normalization ratio is a ratio of the actual MCV value for the second subset of control particles to the second known MCV value when the first subset of control particles is occluded by the plurality of unstabilized RBCs; and determining a normalized high value based on: the second known MCV value and a third known MCV value, wherein the third known MCV value is a known MCV value corresponding to the third subset of control particles; and a high normalization ratio, wherein the high normalization ratio is a ratio of the actual MCV value for the third subset of control particles to the third known MCV value when the third subset of control particles is not occluded by the plurality of unstabilized RBCs, and wherein the high normalization ratio is the ratio of the actual MCV value for the second subset of control particles to the second known MCV value when the third subset of control particles is occluded by the plurality of unstabilized RBCs; and determining the set of MCV values based on the high normalization value and the low normalization value.

27. The method of any of claims 25-26, wherein the method comprises reporting a red blood cell (RBC) count based on measurements of the plurality of unstabilized RBCs.

28. The method of any of claims 23-27, wherein the first subset of control particles, the second subset of control particles, and the third subset of control particles each comprise synthetic control particles.

29. The method of any of claims 23-28, wherein the first subset of control particles, the second subset of control particles, and the third subset of control particles each comprise blood derived cells which have the plurality of different sizes and whose sizes are stabilized with a stabilization agent.

30. The method of claim 29, wherein the stabilization agent is a fixing agent which cross-links the cell membrane.

31. The method of any of claims 29-30, wherein the stabilization agent is glutaraldehyde.

32. A system comprising: one or more processors; a non-transitory computer readable medium having stored thereon instructions for performing the method of any of claims 15-31 when executed using the one or more processors.

33. A non-transitory computer readable medium having stored therein instructions for performing the method of any of claims 15-31.

34. A system comprising a processor and a non-transitory computer readable medium storing instructions operable to, when executed by the processor, perform a set of acts comprising: receiving a control sample, wherein the control sample comprises a set of control particles having a plurality of different sizes; capturing measurements of particles from the set of control particles; andreporting a set of mean corpuscular volume (MCV) values based on the measurements of particles from the set of control particles.

35. The system of claim 34, wherein the set of control particles having the plurality of different sizes comprises blood derived cells which have the plurality of different sizes and whose sizes are stabilized with a stabilization agent.

36. The system of claim 35, wherein the stabilization agent is a fixing agent which cross-links the cell membrane.

37. The system of any of claims 35-36, wherein the stabilization agent is glutaraldehyde.

38. The system of any of claims 35-37, wherein: the set of control particles comprises a set of control particles which are unfixed; and the set of acts comprises reporting a red blood cell count based on measurements of the set of control particles which are unfixed.

39. The system of any of claims 34-38, wherein the set of control particles having the plurality of different sizes comprises a set of synthetic control particles which have the plurality of different sizes.

40. The system of claim 34-39, wherein: the plurality of different sizes comprises a first size range, a second size range and a third size range; the set of control particles having the plurality of different sizes comprises a set of subsets of control particles comprising: a first subset of control particles, wherein each control particle in the first subset of control particles has a size in the first size range;a second subset of control particles, wherein each control particle in the second subset of control particles has a size in the second size range; and a third subset of control particles, wherein the third subset of control particles has a size in the third size range.

41. The system of claim 40, wherein the first size range is between 55 and 60 femtoliters, the second size range is between 85 and 95 femtoliters, and the third size range is between 115 and 125 femtoliters.

42. The system of any of claims 40-41, wherein: the control sample comprises a plurality of unstabilized red blood cells (RBCs), having a range of sizes within a RBC range dispersion between a size of a smallest unstabilized RBC and a size of a largest unstabilized RBC; a maximum of the first size range of the first subset of control particles is less than a minimum of the second size range of the second subset of control particles by at least the RBC range dispersion; and a maximum of the second size range of the second subset of control particles is less than a minimum of the third size range of the third subset of control particles by at least the RBC range dispersion.

43. The system of claim 42, wherein the RBC range dispersion is between 80 and 100 femtoliters.

44. The system of any of claims 42-43, wherein the set of acts comprises: determining a subset of control particles which is occluded by the plurality of unstabilized RBCs wherein the subset of control particles which is occluded by the plurality of unstabilized RBCs is the first subset of control particles, the second subset of control particles, or the third subset of control particles; anddetermining, for each subset of control particles from the set of subsets of control particles, except for the subset of control particles which is occluded by the plurality of unstabilized RBCs, an actual MCV value based on measurements of particles in that subset captured by the analyzer.

45. The system of claim 44, wherein reporting the set of MCV values comprises: determining a normalized low value based on: a first known MCV value and a second known MCV value, wherein the first known MCV value is a known MCV value corresponding to the first subset of control particles, and wherein the second known MCV value is a known MCV value corresponding to the second subset of control particles; and a low normalization ratio, wherein the low normalization ratio is a ratio of the actual MCV value for the first subset of control particles to the first known MCV value when the first subset of control particles is not occluded by the plurality of unstabilized RBCs, and wherein the low normalization ratio is a ratio of the actual MCV value for the second subset of control particles to the second known MCV value when the first subset of control particles is occluded by the plurality of unstabilized RBCs; and determining a normalized high value based on: the second known MCV value and a third known MCV value, wherein the third known MCV value is a known MCV value corresponding to the third subset of control particles; and a high normalization ratio, wherein the high normalization ratio is a ratio of the actual MCV value for the third subset of control particles to the third known MCV value when the third subset of control particles is not occluded by the plurality of unstabilized RBCs, and wherein the high normalization ratio is the ratio of the actual MCV value for the second subset of control particles to the second known MCV value when the third subset of control particles is occluded by the plurality of unstabilized RBCs; anddetermining the set of MCV values based on the high normalization value and the low normalization value.

46. The system of any of claims 41-45, wherein the first subset of control particles, the second subset of control particles, and the third subset of control particles each comprise synthetic control particles.

47. The system of any of claims 41-46, wherein the first subset of control particles, the second subset of control particles, and the third subset of control particles each comprise blood derived cells which have the plurality of different sizes and whose sizes are stabilized with a stabilization agent.

48. A non-transitory computer readable medium having stored thereon a set of instructions for performing the set of acts the instructions the non-transitory computer readable medium of any of claims 34-47 are to perform when executed.

49. A method comprising performing the set of acts the instructions stored on the non- transitory computer readable medium of any of claims 34-47 are to perform when executed.

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