Normal saline medium prevents clotting of menstrual blood
Patent Information
- Application Number
- PCT/CN2025/081199
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2024-03-08
- Filing Date
- 2025-03-07
- Publication Date
- 2025-10-02
AI Technical Summary
Current methods for collecting menstrual blood lack a standardized and effective means to prevent clotting, which compromises the viability and integrity of cells, leading to inaccurate diagnostic results for reproductive and non-reproductive diseases.
Utilizing normal saline as a collection medium to maintain cell viability and prevent clotting of menstrual blood, allowing for prolonged storage and analysis at room temperature.
Normal saline effectively prevents clotting for over 11 hours at room temperature, preserving cell viability and integrity for subsequent laboratory analysis, facilitating the discovery of diagnostic and prognostic biomarkers for conditions like endometriosis and endometrial cancer.
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Figure CN2025081199_02102025_PF_FP_ABST
Abstract
Description
NORMAL SALINE MEDIUM PREVENTS CLOTTING OF MENSTRUAL BLOOD
[0001] CROSS-REFERENCE TO RELATED APPLICATION
[0002] This application claims the benefit of U.S. Provisional Application Serial No. 63 / 562,932, filed March 8, 2024, which is hereby incorporated by reference in its entirety including any tables, figures, or drawings.
[0003] FILED OF INVENTION
[0004] The present invention relates to the collection of menstrual blood to prevent clotting, serving as a valuable source of diagnostic and prognostic biomarkers for detecting reproductive diseases such as endometriosis, endometrial cancer, infertility, cervical cancer and other non-reproductive diseases.BACKGROUND OF THE INVENTION
[0005] The development of molecular and cellular research has enabled non-invasive options to discover diagnostic and prognostic biomarkers of reproductive and non-reproductive diseases.
[0006] Globally, millions of women, particularly those of reproductive age, are suffering from various gynecological cancers and their associated complications. [1, 2] The prevalence of cancer poses a pressing public health concern worldwide, underscoring the importance of early detection and treatment of precancerous conditions to mitigate the substantial burden of morbidity and mortality linked to these diseases. [3] Most importantly, the diagnosis of gynecologic cancers typically necessitates invasive procedures such as surgery, pap smears, colposcopy, or biopsies. [4, 5] Moreover, in regions where access to reproductive healthcare is limited and sterile conditions for such procedures are lacking, individuals may not receive a diagnosis until their cancer has advanced to later stages. Currently, there is lack of non-invasive, definitive, and cost-effective diagnostic methods available for the detection of gynecological cancers and benign uterine conditions, including endometriosis. As a result, utilize menstrual blood as a source of diagnostic and prognostic toolfor various reproductive health issues has high potential.
[0007] Menstrual blood is a complex biological fluid contains potential sources immune cells, endometrial cells, and different proteins that is a potential source of biomarkers for the detection of endometriosis. [6] Physiologically, menstrual blood may not clot inside the body because it contains enzymes such as plasminogen activators that converts plasminogen to plasmin, the primary enzyme involved in dissolving blood clots. However, women with different gynecological disorders such as myoma, abnormal uterine building, endometriosis, and endometrial cancer may experience clotting of menstrual blood. [7] Therefore, menstrual blood could be a potential source for the detection of biomarkers for gynecological and non-gynecological diseases. In addition, menstrual blood also a potential diagnostic method for forensic medicine as it has high concentration of D-dimer in the blood compared to other body fluids and peripheral blood. [8]
[0008] Line of evidence showed that characterization of endometrial tissues in menstrual effluent can serve as an efficientscreening tool for identifying endometriosis in patients with chronic symptoms suggestive of this disorder. [9, 10] Recently, two biomarkers C-X-Cmotif chemokine ligand 5 (CXCL5) and interleukin-1 receptor antagonist protein (IL1RN) protein expression is significantly increased in menstrual blood of patients with endometriosis, indicating that these proteins could be potential biomarkers to diagnose endometriosis and provide insight regarding the pathophysiology of the disease.
[0011] So far, studies showed menstrual blood could be the potential source of discovery of diagnostic biomarkers to detect endometriosis, however, the methods used to handle, prepare, and transfer menstrual samples are variable and not explicitly stated. These variations could potentially result in discrepancies in results and lead to inaccurate interpretation and conclusion of the findings.
[0009] Since menstrual blood is collected by the donor or patient, it can take several hours or even days to arrive at laboratory facilities. As a result, the blood becomes clotted, and the viability of the cells is reduced, resulting in poor cell integration and erroneous and inconclusive results. To date there is no appropriate and standard menstrual blood collection medium that is feasible, convenient, and friendly to be done by the women herself, to prevent clotting.
[0010] Previous studies demonstrated that 0.9%saline can be used to store goat ovarian follicles for further downstream analysis. Santos RRD et al. (2002) examined the effect of 0.9%saline solution and Phosphate Buffered Saline (PBS) on the quality of goat preantral follicles under varying temperatures and incubation durations. The study found that storing ovarian fragments in either 0.9%saline or PBS at 4 ℃ didn’t significantly decrease the percentage of normal follicles compared to control samples. However, significant reduction in normal follicle percentages was observed after 24 hours of preservation in 0.9%saline solution. Additionally, when ovarian fragments were maintained at 20 ℃ or 39 ℃ in PBS, there was a decline in the percentage of normal preantral follicles compared to controls, except after preservation at 20℃ for 4 hrs. Finally, this study concluded that goat preantral follicles can be safely stored at 4 ℃ in 0.9%saline solution for 12 hours, in PBS for 24 hours, and at 20 ℃in PBS for 4 hours.
[0012]
[0011] PBS is an isotonic buffer solution that has a different composition compared to normal saline. PBS contains 254 mEq / L of sodium chloride (NaCl) , 5.4 mEq / L of potassium chloride (KCl) , 20 mEq / L of sodium phosphate dibasic (Na2HPO4) , and 3.6 mEq / L of potassium phosphate monobasic (KH2PO4 whereas 0.9%saline consists of sodium (Na+) and chloride (Cl-) at concentrations of 154 mEq / L each per liter. Phosphate compounds in PBS provide a stable physiological pH value in the biological sample whereas sodium chloride provides osmotic protection of microbial cells, which prevents lysis and shrinkage. Moreover, both PBS and 0.9%saline are isotonic solutions which could maintain cell integrity and viability. [13, 14]
[0012] Another animal (healthy dog) study showed that blood to 0.9%saline dilution (1: 3 or 1: 10) didn’t significantly affect the coagulation compared to hydroxyethyl starch (HES) .
[0015] In conclusion, there is a lack of studies to examine the effect of PBS and saline on cell integrity, viability and morphological changes in human biological and in vitro blood samples.
[0013] Evidence showed that the pH of PBS and 0.9%saline solutionis (7-7.4) and (4-5-7) respectively. Both PBS and saline have similar osmotic pressure to human body fluids, providing crucial role in maintaining cell integrity during experiments. Previous studies showed that increasing pH could promote platelet aggregation, platelet calcium and serotonin release as well as platelet factor III availability. Additionally, the prothrombin time (PT) and partial thromboplastin time (PTT) decreased when the pH increases from 5-7.6. This suggests that higher pH levels can activate or enhance the blood clotting mechanism. [16, 17]
[0014] Menstrual blood could be a potential and useful source to diagnose endometriosis and endometrium related diseases as the bloodshed of ectopic endometrium directly from the functionalis layer of the endometrium contains fluids, viable cells, immune cells, nucleic acids, and proteins with similar cellular, molecular, and biological profiles as of ectopic endometrium in endometriosis and other reproductive tract diseases.
[0015] Due to the unique composition and nature of menstrual blood and its potential applications for various gynecological and non-gynecological conditions such as endometriosis, cervical cancer, endometrial cancers, and diabetes mellitus, there is a highly demand for standardized protocols for the collection and preservation of menstrual blood. Consequently, we evaluated the effects of normal saline on complete blood count, clotting, and cell viability.
[0016] Thus, there is a need to develop methods and strategies to avoid menstrual blood clotting in order to investigate diagnostic and prognostic biomarkers of both reproductive and non-reproductive diseases.
[0017] BRIEF SUMMARY OF THE INVENTION
[0018] The subject invention pertains to techniques for discovering new and potentially diagnostic andprognostic biomarkers in menstrual blood for various gynecological diseases, including endometriosis, gynecological cancers, and other non-reproductive diseases. This is achieved by developing a new collectionmedium for menstrual blood that maintains the number of blood cellsand their viability at, for example, room temperature.
[0019] This subject invention solves problems during menstrual blood collection and handling. It can also beused to explore novel and potential diagnostic and prognostic biomarkers as well as insights to understand the pathophysiology of the diseases. Thus, this invention translates the clinical utility of menstrual blood on the era of diagnostic biomarkers of endometriosis and other diseases. Further, the method of the subject invention keeps the blood cells (number andviability) safe for laboratory studies or analysis. The sample collection method is easy, feasible, convenient and cost effective.
[0020] In one embodiment, the subject invention provides a collection medium of menstrual blood for further research, which leads to the discovery of diagnostic biomarkers for reproductive and non-reproductive disorders, as well as understanding the disease's pathophysiology. Advantageously, such medium helps to safely keep the sample until isolation of mononuclear cells, stem cells, and plasma for advanced molecular and cellular analysis through prevention of clotting that affects the integration, and viability of cells.
[0021] In a specific embodiment, the collection medium is normal saline, whichcan preventcoagulation of menstrual blood and preserve cell viability in the sample at, for example, room temperature. Moreover, menstrual blood samples can be collected and handled by adding normal saline at roomtemperature, which does not reduce the amount of complete blood counts and avoids blood clotting whilemaintaining good preservation of cell viability.
[0022] In certain embodiments, the subject invention pertains to:
[0023] A) evaluating the status of menstrual blood clotting after, e.g., 6-24 hours of collection withnormal saline, e.g., 0.9% (w / v) sodiumchloride injection, for example, at room temperature, 4℃, or any temperature therebetween;
[0024] B) the development of a standard menstrual blood collection method;
[0025] C) assessing the cell viability, and number of blood cells at both room temperature and / or 4℃, or any temperature therebetween, with normal saline, e.g., 0.9% (w / v) sodium chloride, injection; and / or
[0026] D) establishing menstrual blood derived diagnostic biomarkers for reproductive diseases such asendometriosis, poly cystic ovarian syndrome, endometrial cancers, cervical cancers, and others.
[0027] In one embodiment, the subject invention provides a method for inhibiting / reducing coagulation of menstrual blood, the method comprising collecting a menstrual blood sample from a subject; and adding a collection medium in the menstrual blood sample to inhibit / reduce coagulation of menstrual blood in the sample.
[0028] In one embodiment, the subject invention provides a method for preserving cell viability in a menstrual blood sample, the method comprising collecting the menstrual blood sample from a subject; and adding a collection medium in the menstrual blood sample to preserve cell viability in the menstrual blood sample.
[0029] In one embodiment, the subject invention provides a method for storing a menstrual blood sample without clotting, the method comprising obtaining the menstrual blood sample from a subject; adding a collection medium in the menstrual blood sample; and storing the menstrual blood sample.
[0030] In a specific embodiment, the collection medium is normal saline. In a specific embodiment, the normal saline isan isotonic solutioncomprising 0.9% (w / v) NaCl.
[0031] In a specific embodiment, the collection medium is added at a collection medium to menstrual blood ratio of 0: 1, 1: 1, 1: 2, 1: 3, 1: 4, 1: 5, 2: 1, 3: 1, 4: 1, or 5: 1.
[0032] In certain embodiments, the method further comprises evaluating the status of menstrual blood clotting in the menstrual blood sample, and / or evaluating cell viability in the menstrual blood sample.
[0033] In some embodiments, the subject invention shows thatnormal saline can be used to avoid menstrual blood clotting for more than 11 hours at room temperature, and good cell viability and count have been observed at both 4℃ and room temperature with the addition of normal saline. It is practical to collect menstrual samples at room temperature by mixing thenormal saline into the blood.BRIEF DESCRIPTION OF THE DRAWINGS
[0034] Figure 1: Sample preparation.
[0035] Figure 2: Cell Viability (Mean with SD) .
[0036] Figure 3: Clotting profile of sample1.
[0037] Figure 4: Clotting profile of sample2.
[0038] Figure 5: Clotting profile of sample 3.
[0039] Figure 6: White blood cell count (Mean with SD) .
[0040] Figure 7: Red blood cell count (Mean with SD) .
[0041] Figure 8: Platelet cell count (Mean with SD) .
[0042] Figure 9: Endometrial cells count (Mean with SD) .
[0043] DETAILED DISCLOSURE OF THE INVENTION
[0044] The subject invention pertains to techniques for discovering new and potentially diagnostic andprognostic biomarkers in menstrual blood for various gynecological diseases, including endometriosis, gynecological cancers, and other non-reproductive diseases. These biomarkers include miRNA biomarkers for forensic use, human papillomavirus detection for cervical cancer, immune cell markers for identifying recurrent pregnancy loss and unexplained infertility, as well as angiogenic and inflammatory markers for endometriosis. This is achieved by developing a new collectionmedium for menstrual blood that maintains the number of blood cellsand their viability at, for example, room temperature.
[0045] This subject invention addresses challenges related to menstrual blood collection and handling. It can also be utilized to discover novel and promisingdiagnosticand prognostic biomarkers as well as to gain insights into the pathophysiology of the related diseases. Importantly, the subject invention contributes to collecting, transporting, and processing menstrual blood.
[0046] Additionally, the invention includes methods for utilizing a dye test to differentiate between living and dead cellsin a sample. Normal saline can be used to preventcoagulation of menstrual blood and preserve cell viability in the sample at room temperature. Moreover, menstrual blood samples can be collected and handled by adding normal saline at roomtemperature, which does not reduce the amount of complete blood counts and avoids blood clotting whilemaintaining good preservation of cell viability.
[0047] Advantageously, the method of the subject invention keeps the blood cells (number andviability) safe for laboratory studies or analysis. The sample collection method was easy, feasible, convenient, and cost effective.
[0048] In one embodiment, the subject invention provides a collection medium of menstrual blood for further research, which leads to the discovery of diagnostic biomarkers for reproductive and non-reproductive disorders, as well as understanding the disease's pathophysiology. Advantageously, such medium helps to safely keep the sample until isolation of mononuclear cells, stem cells, and plasma for advanced molecular and cellular analysis through prevention of clotting that affects the integration and viability of cells.
[0049] In a specific embodiment, the collection medium is normal saline. In a preferred embodiment, normal saline comprises about 0.9%NaCl (w / v) (e.g., 0.9 g of salt (NaCl) per 100 ml of solution) . Surprisingly, the subject invention shows that normal saline could be used to avoid menstrual blood clotting for more than about 11 hours at room temperature.
[0050] In a specific embodiment, the normal saline comprises 154 mEq / L sodium and 154 mEq / L chloride.
[0051] In one embodiment, the subject invention provides a method that allows to collect and store the menstrual bloodsample for longer periods of time without clotting while, at the same time, being able to perform analyses of the sample in terms of particular biomarkers for reproductive and non-reproductive disorders.
[0052] In one embodiment, the subject invention provides a method for preventing clotting of menstrual blood, the method comprising collecting a menstrual blood sample from a subject; and adding a collection medium in the menstrual blood sample to prevent clotting of the menstrual blood in the sample.
[0053] In one embodiment, the subject invention provides a method for preventing coagulation of menstrual blood, the method comprising collecting a menstrual blood sample from a subject; and adding a collection medium in the menstrual blood sample to prevent coagulation of the menstrual blood in the sample.
[0054] In certain embodiments, the step of adding the collection medium in the menstrual blood sample is carried out immediately after collecting the menstrual blood sample. The term “immediately” , as used herein, is meant to refer to a period of time that ranges from 0.5 seconds to 2 minutes, preferably 0.5 seconds to 20 seconds, more preferably 0.5 seconds to 5 seconds.
[0055] In certain embodiments, the step of adding the collection medium in the menstrual blood sample is carried out after a period of time once the menstrual blood sample is collected. In certain embodiments, the period of time may be, for example, from about 1 minute to about 11 hours, from about 1 minute to about 10 hours, from about 1 minute to about 9 hours, from about 1 minute to about 8 hours, from about 1 minute to about 7 hours, from about 1 minute to about 6 hours, from about 1 minute to about 5 hours, from about 10 minutes to about 5 hours, from about 10 minutes to about 7.5 hours, from about 20 minutes to about 5 hours, from about 30 minutes to about 4 hours, from about 40 minutes to about 3 hours, from about 50 minutes to about 2 hours, or from about 1 to about 4 hours. In certain embodiments, the period of time may be, for example, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 15, 20, 25, 30, 40, 50, or 60 minutes.
[0056] In one embodiment, the subject invention provides a method for slowing down the clotting of menstrual blood, the method comprising collecting a menstrual blood sample from a subject; and adding a collection medium in the menstrual blood sample to slow down clotting of menstrual blood in the sample.
[0057] In one embodiment, the subject invention provides a method for suppressing the clotting of menstrual blood, the method comprising collecting a menstrual blood sample from a subject; and adding a collection medium in the menstrual blood sample to suppress clotting of menstrual blood in the sample.
[0058] In certain embodiments, the step of adding a collection medium to the menstrual blood sample is to dilute the menstrual blood in order to prevent or slow down the clotting of the menstrual blood in the sample. In certain embodiments, the collection medium is added at a ratio (collection medium: menstrual blood) of, for example, 0: 1, 1: 1, 1: 2, 1: 3, 1: 4, 1: 5, 1: 6, 1: 7, 1: 8, 1: 9, 1: 10, 2: 1, 3: 1, 4: 1, 5: 1, 6: 1, 7: 1, 8: 1, 9: 1, or 10: 1. In certain embodiments, the collection medium is added at a ratio (collection medium: menstrual blood) , for example, between 10: 1 and 1: 10, between 5: 1 and 1: 5, or between 2: 1 and 1: 2.
[0059] In one embodiment, the subject invention provides a method for inhibiting / reducing coagulation of menstrual blood, the method comprising collecting a menstrual blood sample from a subject; and adding a collection medium in the menstrual blood sample to inhibit coagulation of menstrual blood in the sample.
[0060] In one embodiment, the method of the subject invention may also comprise evaluating the status of menstrual blood clotting after the addition of the collection medium. In a further embodiment, such evaluation can be carried out, for example, every 10 minutes, every 20 minutes, every 30 minutes, every hour, every 2 hours, every 3 hours, every 4 hours, or every 5 hours. In a further embodiment, such evaluation can be carried out, for example, at least 0.5, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, or 24 hours after the addition of the collection medium.
[0061] In one embodiment, the subject invention provides a method for preserving cell viability in a menstrual blood sample, the method comprising collecting the menstrual blood sample from a subject; and adding a collection medium in the menstrual blood sample to preserve cell viability in the menstrual blood sample.
[0062] In certain embodiments, the methods of the subject invention are carried out at room temperature, or 4℃, or any temperature in between.
[0063] In one embodiment, the subject invention provides a method for preparing a menstrual blood sample of a subject for subsequent:
[0064] a) genotyping such menstrual blood sample;
[0065] b)detection of biomarkers (e.g., nucleic acids, lipids, proteins, peptides, and combinations thereof) in such menstrual blood sample for reproductive and non-reproductive disorders, preferably, endometriosis, PCOS, endometrial cancers, and cervical cancers;
[0066] c)isolation of mononuclear cells, stem cells, white blood cells, red blood cells, platelet (PLT) , immune cells, and / or plasma; and / or
[0067] d) storing and preserving said menstrual blood sample for later use,
[0068] wherein the method comprises obtaining the menstrual blood sample from the subject; and adding a collection medium in the menstrual blood sample.
[0069] In some embodiments, genotyping may include, for example, identification of restriction fragment length polymorphisms (RFLP) , random amplified polymorphic detection (RAPD) of genomic DNA, amplified fragment length polymorphism detection (AFLPD) , polymerase chain reaction (PCR) , DNA sequencing, allele specific oligonucleotide (ASO) probes, hybridization to nucleic acid microarrays or beads. In certain embodiments, the prepared menstrual blood sample may be further processed to detect, for example, nucleic acids or proteins. Detection of nucleic acids can be done, for example, using appropriate nucleic acid technology, e.g., suitable amplification / detection methodology, such as hybridization experiments, real-time PCR, hybridization on a microarray or chip or bead on which appropriate nucleic acid probes are immobilized, etc. Detection of proteins may occur, for example, via immunosorbent assays, involving appropriate antibodies. A typical example of such an immunosorbent assay is an ELISA.
[0070] In one embodiment, the subject invention provides a method for storing a menstrual blood sample without clotting, the method comprising obtaining the menstrual blood sample from a subject; adding a collection medium in the menstrual blood sample; and storing the menstrual blood sample.
[0071] In one embodiment, the menstrual blood sample is stored at room temperature, or 4 ℃, or any temperature in between.
[0072] In one embodiment, the method of the subject invention may further comprise evaluating cell viability in the menstrual blood sample, which can be used to determine how and how long the sample can be stored. Advantageously, results of the subject invention show good cell viability and count at both 4 ℃ and room temperature with the addition ofnormal saline.
[0073] In some embodiments, the menstrual blood sample may be stored in the collection medium according to the present invention for extended periods of time, such as several days, several weeks to months. An exemplary period of such storage of the menstrual blood sample is 1 week to 12 months, e.g., 2, 3, 4 weeks, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, or 12 months.
[0074] In certain embodiments, the subject invention pertains to:
[0075] A) evaluating the status of menstrual blood clotting after, e.g., 6-24 hours of collection with an normal saline, e.g., 0.9%sodiumchloride injection, for example, at room temperature and / or 4℃;
[0076] B) the development of a standard menstrual blood collection method;
[0077] C) assessing the cell viability, and number of blood cells at both room temperature and / or 4℃ withthe normal saline, e.g., 0.9%sodium chloride, injection; and / or
[0078] D) establishing menstrual blood derived diagnostic biomarkers for reproductive diseases such asendometriosis, PCOS, endometrial cancers, cervical cancers, and others.
[0079] In certain embodiments, the subject invention provides a method comprising:
[0080] a) obtaining a menstrual blood sample from the subject;
[0081] b) evaluating the clotting status of menstrual blood over time;
[0082] c) determining the complete blood count and its differential morphology of each component;
[0083] d) determining the percentage of cell viability across different samples over time under different samplestorage methods; and / or
[0084] e) identifying endometrial cells from the total blood cells in the sample,
[0085] wherein the subject is likely to be healthy (no known medical, surgical and gynecological diseases; self-reported) .
[0086] In a specific embodiment, the complete blood count includes red blood cells, white blood cells andplatelets with differential indices.
[0087] In specific embodiments, the endometrial cells comprise epithelial cells, stromal cells, immune cells, endothelial cells, progenitor cells, stem cells, and / or any combination thereof.
[0088] In a specific embodiment, the normal saline is normal saline comprising 0.9%NaCl.
[0089] In one embodiment, the subject invention provides a method for evaluating the clotting status of menstrual blood, the method comprising collecting a menstrual blood sample from a subject; adding a collection medium in the menstrual blood sample; and evaluating the clotting status of menstrual blood sample.
[0090] In a further embodiment, the step of evaluating can be carried out, for example, every 10 minutes, every 20 minutes, every 30 minutes, every hour, every 2 hours, every 3 hours, every 4 hours, or every 5 hours. In a further embodiment, such evaluation can be carried out, for example, at least 0.5, 1, 2, 3, 4, 5, 6, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, or 24 hours after the addition of the collection medium.
[0091] In one embodiment, the subject invention provides a method for collecting menstrual blood, the method comprising obtaining a menstrual blood sample from a subject; and adding a collection medium in the menstrual blood sample to obtain a menstrual blood collection, which can be used for later testing.
[0092] In one embodiment, the subject invention provides a method for assessing cell viability of menstrual blood, the method comprising collecting a menstrual blood sample from a subject; adding a collection medium in the menstrual blood sample; and evaluating the cell viability of the menstrual blood sample.
[0093] In one embodiment, the subject invention provides a method for identifying biomarkers for endometriosis from menstrual blood, the method comprising collecting a menstrual blood sample from a subject; adding a collection medium in the menstrual blood sample; and determining the biomarkers for endometriosis from the menstrual blood sample.
[0094] In one embodiment, the subject invention provides a method for detecting endometriosis in a subject, the method comprising collecting a menstrual blood sample from the subject; adding a collection medium in the menstrual blood sample; determining a biomarker for endometriosis from the menstrual blood sample; and detecting endometriosis in the subject if the biomarker for endometriosis is present in the menstrual blood sample.
[0095] In one embodiment, the subject invention provides a method of treating endometriosis, the method comprising detecting endometriosis in the subject; and administering a therapy to treat endometriosis in the subject.
[0096] In one embodiment, the subject invention employsa dye test for determining the viability of cells in a menstrual blood sample, the dye test comprising, one or more dyes (e.g., acridine orange (AO) and propidium iodide (PI) ) , instructions for obtaining number or percentage of cell viability from menstrual blood from a subject, and / or instructions for determining the number or percentage of live and dead cells per sample and acrossdifferent dilution labels.
[0097] In one embodiment, the dye test is formulated to evaluate the effect of the medium on the viability of cells.
[0098] In certain embodiments, the dye test of the subject invention comprising obtaining a menstrual blood sample from a subject, wherein the menstrual blood sample comprising the collection medium of the subject invention; contacting the menstrual blood sample with one or more dyes, e.g., AO and PI; and evaluating the cell viability from the menstrual blood sample, wherein the step of evaluating may comprise determining the number and / or percentage of live and / or dead cells in the menstrual blood sample.
[0099] In certain embodiments, the subject invention provides a method of analyzing complete blood count and components of a menstrual blood sample, the method comprising obtaining the menstrual blood sample from a subject; and analyzing the menstrual blood sample for the complete blood count and differential morphology count by using, for example, CBC (XN-350) analyzer.
[0100] In some embodiments, the step of analyzing may comprise diluting the menstrual blood sample with normal saline, and / or insert the sample into the analyzer, such as CBC (XN-350) analyzer for the complete blood count and differential morphology count. In specific embodiments, the method determines the main components of the complete blood count such as WBC, RBC, and PLT, and other differential morphology count.
[0101] In certain embodiments, the subject invention provides a method for analyzing cell viability of a menstrual blood sample using Cellometer Dual-Fluorescence Counting, the method comprising obtaining the menstrual blood sample from a subject; diluting the menstrual blood sample with normal saline; mixing the diluted sample with a staining solution, wherein the staining solution comprising a first dye to stain live cells and / or a second dye to stain dead cells; analyzing cell viability of the stained sample using Cellometer Dual-Fluorescence Counting; and optionally determining the percentage of cell viability across different samples over time in different sample storage methods.
[0102] Any compositions or methods provided herein can be combined with one or more of any of the other compositions and methods provided herein.
[0103] As used herein, the phrase “menstrual effluent” refers to complex fluid compromised of blood, vaginal secretions, and endometrial tissues.
[0104] As used herein, the term “Menstruation” refers tothe regular discharge of blood and mucosal tissue from the inner lining of the uterus through the vagina.
[0105] As used herein, the phrase “menstrual blood” refers to partly blood and partly tissue from the inside of the uterus.
[0106] As used herein, an isotonic solution has the same solute concentration compared to the intracellular solute concentration. For example, when a cell is placed in an isotonic solution, there will be no net movement of water. Both the concentration of solute and water are equal both intracellularly and extracellularly. Thus, there will be no net movement of water towards the solution or the cell. The cell and the environment around it are in equilibrium, and the cell should remain unchanged.
[0107] As used herein, menstrual blood derived cells refer to a cell population isolated from menstrual blood of humans. These cells may be extracted through adherence to a culture plate, and further selected by fluorescence activated cell sorting. Red blood cell lysis may be done after collection of menstrual blood. Density gradient centrifugation can be used to collect the cell population capable of forming tunneling nanotubes.
[0108] “Treatment” or “treating” (and grammatical variants of these terms) , as used herein, refer to an approach for obtaining beneficial or desired results including but not limited to therapeutic benefit. A therapeutic benefit is achieved with the eradication or amelioration of one or more of the physiological symptoms associated with the underlying infection such that an improvement is observed in the subject, notwithstanding that the subject may still be afflicted with the underlying infection.
[0109] The terms “treatment” or any grammatical variation thereof (e.g., treat, treating, etc. ) , as used herein, includes but is not limited to, the application or administration to a subject (or application or administration to a cell or tissue from a subject) with the purpose of slowing, stabilizing, curing, healing, alleviating, relieving, remedying, less worsening, ameliorating, or improving the disease or condition. The term “treating” refers to any indication of success in the treatment or amelioration of a pathology or condition, including any objective or subjective parameter such as abatement; remission; lessening of the rate of worsening; lessening severity of the disease; stabilization, diminishing of symptoms or making the pathology or condition more tolerable to the subject; or improving a subject’s physical or mental well-being.
[0110] The term “prevention” or any grammatical variation thereof (e.g., prevent, preventing, etc. ) , as used herein, includes but is not limited to, at least the reduction of likelihood of the risk of (or susceptibility to) acquiring a condition. The term “prevention” may refer to avoiding, delaying, forestalling, or minimizing one or more unwanted features associated with a condition, and / or completely or almost completely preventing the development of a condition. Prevention can further include, but does not require, absolute or complete prevention, meaning the condition may still develop at a later time and / or with a lesser severity than it would without preventative measures.
[0111] The term “effective amount” refers to that amount of normalsaline described herein that is sufficient to effectively prevent clotting of menstrual blood. The effective amount may vary depending upon the subject, e.g., the weight and age of the subject, and the disease or condition the subject may have, and when the menstrual blood was collected, which can readily be determined by one of ordinary skill in the art. The specific amount will vary depending on the particular dosing, whether it is used in combination with other compounds, timing, etc.
[0112] “Subject” refers to an animal, such as a mammal, for example a human. The methods described herein can be useful in both pre-clinical human therapeutics and veterinary applications. In some embodiments, the subject is a mammal (such as an animal model of disease) , and in some embodiments, the subject is human. Non-limiting examples of subjects include canine, porcine, rodent, feline, bovine, poultry, equine, human, and a non-human primate.
[0113] As used herein, the singular forms “a” , “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. Furthermore, to the extent that the terms “including” , “includes” , “having” , “has” , “with” , or variants thereof are used in either the detailed description and / or the claims, such terms are intended to be inclusive in a manner similar to the term “comprising” . The transitional terms / phrases (and any grammatical variations thereof) “comprising, ” “comprises, ” “comprise, ” can be used interchangeably.
[0114] The phrases “consisting essentially of” or “consisting essentially of” indicate that the claim encompasses embodiments containing the specified materials or steps and those that do not materially affect the basic and novel characteristic (s) of the claim.
[0115] The transitional term “comprising, ” “comprises, ” or “comprise” is inclusive or open-ended and does not exclude additional, unrecited elements or method steps. By contrast, the transitional phrase “consisting of” excludes any element, step, or ingredient not specified in the claim. The phrases “consisting” or “consists essentially of” indicate that the claim encompasses embodiments containing the specified materials or steps and those that do not materially affect the basic and novel characteristic (s) of the claim. Use of the term “comprising” contemplates other embodiments that “consist” or “consisting essentially of” the recited component (s) .
[0116] The term “about” means within an acceptable error range for the particular value as determined by one of ordinary skill in the art, which depends in part on how the value is measured, i.e., the limitations of the measurement system. In the context of compositions containing amounts of ingredients where the term “about” is used, these compositions contain the stated amount of the ingredient with a variation (error range) of 0-10%around the value (X ± 10%) . In other contexts, the term “about” provides a variation (error range) of 0-10%around a given value (X ± 10%) . As is apparent, this variation represents a range that is up to 10%above or below a given value, for example, X ± 1%, X ± 2%, X ± 3%, X ± 4%, X ± 5%, X ± 6%, X ± 7%, X ± 8%, X ± 9%, or X ± 10%.
[0117] In the present disclosure, ranges are stated in shorthand to avoid having to set out at length and describe each and every value within the range. Any appropriate value within the range can be selected, where appropriate, as the upper value, lower value, or the terminus of the range. For example, a range of 0.1-1.0 represents the terminal values of 0.1 and 1.0, as well as the intermediate values of 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, and all intermediate ranges encompassed within 0.1-1.0, such as 0.2-0.5, 0.2-0.8, 0.7-1.0, etc. Values having at least two significant digits within a range are envisioned, for example, a range of 5-10 indicates all the values between 5.0 and 10.0 as well as between 5.00 and 10.00 including the terminal values. When ranges are used herein, combinations and sub-combinations of ranges (e.g., subranges within the disclosed range) and specific embodiments therein are explicitly included.
[0118] Exemplary embodiments of the subject invention include:
[0119] Embodiment 1. A method of analyzing complete blood count and components, the method comprising:
[0120] (A) obtaining a menstrual blood sample;
[0121] optionally, diluting the menstrual blood sample with normal saline; and
[0122] determining complete blood count and differential morphology of each component of the menstrual blood sample; and / or
[0123] (B) obtaining a menstrual blood sample;
[0124] diluting the menstrual blood sample with normal saline;
[0125] optionally, storing the diluted sample for a period of time at room temperature, 4 ℃, or any temperature therebetween;
[0126] mixing the menstrual blood sample with a staining solution; and
[0127] determining cell viability of the stained sample.
[0128] Embodiment 2. The method of embodiment 1, wherein the complete blood count comprises counts of red blood cells, white blood cells, and platelets with differential indices.
[0129] Embodiment 3. The method of embodiment 1 or 2, wherein endometrial cells are identified from the menstrual blood sample.
[0130] Embodiment 4. The method of any preceding embodiment, wherein endometrial cells comprise epithelial cells, stromal cells, immune cells, endothelial cells, progenitor cells, stem cells, or any combination thereof.
[0131] Embodiment 5. The method of any preceding embodiment, wherein the normal saline comprises 0.9%NaCl.
[0132] Embodiment 6. The method of any preceding embodiment, wherein the normal saline is PBS.
[0133] Embodiment 7. The method of any preceding embodiment, wherein the staining solution comprises acridine orange (AO) and propidium iodide (PI) .
[0134] Embodiment 8. A method for slowing down / reducing coagulation of menstrual blood, the method comprising collecting a menstrual blood sample from a subject; and adding a collection medium in the menstrual blood sample to slow down / reduce coagulation of menstrual blood in the sample.
[0135] Embodiment 9. The method of embodiment 8, wherein the subject is a human.
[0136] Embodiment 10. The method of embodiment 8 or 9, wherein the collection medium is a normal saline.
[0137] Embodiment 11. The method of embodiment 10, wherein the normal saline comprises 0.9 %NaCl.
[0138] Embodiment 12. The method of any preceding embodiment, wherein the step of adding the collection medium in the menstrual blood sample is carried out immediately after collecting the menstrual blood sample.
[0139] Embodiment 13. The method of any preceding embodiment, wherein the collection medium is added at a collection medium to menstrual blood ratio of 0: 1, 1: 1, 1: 3, or 3: 1.
[0140] Embodiment 14. The method of any preceding embodiment, further comprising evaluating the status of menstrual blood clotting.
[0141] Embodiment 15. The method of any preceding embodiment, further comprising evaluating cell viability in the menstrual blood sample.EXAMPLES
[0142] All patents, patent applications, provisional applications, and publications referred to or cited herein are incorporated by reference in their entirety, including all figures and tables, to the extent they are not inconsistent with the explicit teachings of this specification.
[0143] The following are examples that illustrate procedures for practicing the invention. These examples should not be construed as limiting. All percentages are by weight and all solvent mixture proportions are by volume unless otherwise noted.
[0144] Materials and methods
[0145] Menstrual blood collection
[0146] Informed verbal consent was taken before collection. Some sociodemographic and obstetric related factors were also assessed with semi-structured questionnaire. Flyer was provided on how to collect menstrual blood. The donor was instructed to collect menstrual blood with red specimen collection bottle when she feels flow of menstrual blood and the donor was advised to discard the blood if any contamination exists with urine during collection. Immediately after she finished the collection, the sample was transferred and diluted withnormal saline within 10 minutes.
[0147] 42-year-old reproductive women having one prior history of abortion were recruited for this study. Menstrual blood was collected 3 times in day 2 and 3 of the menstruation. After collection, storage (with observation to assess the status of clotting) and transferring of the samples for further analysis to check the cell count and viability.
[0148] The Sysmex XN-350 fully automated hematology analyzer was utilized for complete blood count analysisand its differential, while the Cellometer K2 machine was used to count the cell viability across thesamples. The Cellometer Dual-Fluorescence Counting Method was employed to determine cell viabilityand count according to the company protocol. A sample preparation protocol was developed to assessthe effect ofnormal saline on menstrual blood clotting, with a detailed and clear samplepreparation protocol.
[0149] Materials and logistics
[0150] 1. 1.5-2μL Eppendorf for CBC and viability test preparation
[0151] 2. Specimen bottle (red cap) -100ml
[0152] 3. Normal saline: 0.9%sodium chloride injection B.P. (10ml) , (154 mEq / L sodium and 154 mEq / L chloride)
[0153] 4. Wet ice (1ooml)
[0154] 5. Fridge (4℃)
[0155] Sample preparation protocol
[0156] To evaluate the effect ofnormal saline on menstrual blood clotting, the following sample preparation protocol was developed. Different dilution labels and storage types were used to investigate the effect of normal saline on menstrual blood clotting and whether it is effective to avoid menstrual blood clotting and preserves the viability of the cells (Figure 1) . Moreover, four preparations in each storage type (4 at room temperature, and 4 at 4℃) were prepared as stated in Table 1.
[0157] Table 1: sample preparation protocol
[0158] Cell viability test -Acridine orange (AO) and propidium iodide (PI) analysis
[0159] Cell viability and count is employed by Cellometer Dual-Fluorescence Counting Method as per the company protocol:
[0160] 1) Dilute menstrual blood sample 1: 10 with PBS.
[0161] 2) Combine 20 μl of diluted sample with 20 μl of AO / PI Staining Solution.
[0162] 3) Add 20 μl of stained sample to the Cellometer Counting Chamber and insert into and insert into a Cellometer automated cell counter.
[0163] 4) The Cellometer system automatically captures and analyzes bright field and fluorescent images.
[0164] 5) The automated data report provides cell count, concentration, and mean diameter for both live and dead nucleated cells along with the %viability for the sample.
[0165] Complete blood count test (CBC)
[0166] CBC with differential was calculated with Compact 5-part differential CBC (XN-350) analyzer. 25 μL aspiration volume in whole blood was needed to provide differential morphology count, with its detail graph. Even though the main component of CBC (WBC, RBC, PLT) were reported, other differential morphology counts were also done. All the Red blood cell (RBC) indices such as Hemoglobin (HGB) , hematocrit (HCT) , mean corpuscular volume (MCV) , mean corpuscular hemoglobin (MCH) , mean corpuscular hemoglobin concentration (MCHC) , &red cell distribution width (RDW-CV) , and white blood cell (WBC) indices; neutrophil, lymphocyte, monocyte, eosinophil, and basophil were also investigated.
[0167] EXAMPLE 1-DEMOGRAPHICS
[0168] 42-year-old reproductive women having one prior history of abortion were recruited for this study. Menstrual blood was collected 3 times in different days and months of the menstrual cycle of Donor 1. Donor 1 had a history of one spontaneous abortion, otherwise she had no remarkable history of autoimmune disease and previous surgery (Table 2) .
[0169] Table 2: Demographic characteristics of the donor
[0170] The sample was collected in three different menstrual cycles from the same donor. A sufficient volume of blood was collected for this study. During the second sample collection, clots also existed with the blood during collection. The clot was discarded, and the blood was prepared for further analysis. The blood was diluted with normal saline as per the sample preparation protocol to look for cell viability, CBC, and clotting status of each sample at different time spot (Table 3) .
[0171] Table 3: Sample characteristics
[0172] After collection of menstrual blood, the sample was stored at 4℃ and room temperature for 7.5-8 hours, then CBC and cell viability tests are carried out. To compare and investigate the difference between keeping samples in different storage mediums for 7.5-8 hours and 10-10.5 hours, the first processed sample was also re-stored and re-analyzed after 2.5 hours. The percentage of cell viability and CBC was presented by mean with standard deviation (Mean with SD) .
[0173] EXAMPLE 2-CELL VIABILITY
[0174] This study revealed that the viability of cells is good enough at room temperature when menstrual blood was diluted with normal saline. This indicates that normal saline can keep the viability of cells by avoiding menstrual clot at room temperature. In addition, the more diluted the blood is, the more viable the cells are at room temperature. Furthermore, this study revealed that normal saline could avoid clotting of menstrual blood and help finding adequate live cells for menstrual blood experimental studies (Figure 2) .
[0175] EXAMPLE 4-MENSTRUAL BLOOD CLOTTING STATUS
[0176] Menstrual blood clotting was assessing with observation and reported as yes (clotted) and no (non-clotted) over time series. As Figure 3 illustrates, dilution with normal saline can avoid clotting of menstrual blood at room temperature. Blood only sample at room temperature becomes completely clotted. Thus, adding normal saline can be used process menstrual blood at room temperature (Figure 3) . Even though the second sample result also showed that saline has a role to avoid menstrual blood, some inconsistent result was seen (Figure 4) . This discrepancy might be due to 1) the day of menstrual blood collection is different, which is day 3 for the latter sample, 2) the second sample had clotting at initial during collection. As a result, we arranged sample 3 to investigate the discrepancy between sample 1 and sample 2. The result shows that normal saline can avoid menstrual blood clotting in both 4℃ and room temperature for more than 11 hours and about 27 hours with slight clot (approximately 5-10%) (Figure 5) .
[0177] EXAMPLE 3-COMPLETE BLOOD COUNT
[0178] The complete blood count analysis showed that white blood count (WBC) (Fig. 6) , red blood count (RBC) (Fig. 7) and platelet (PLT) (Fig. 8) numbers decrease when the sample is more diluted at both 4℃ and RT compared to blood only samples. In addition, numbers of endometrial cells decrease when the sample is more diluted compared to undiluted samples (Fig. 9) . Moreover, the number of RBC, PLT, WBC and endometrial cells decreases when increasing the dilution ratio compared to blood only samples and less diluted samples (Table 4) .
[0179] EXAMPLE 4-MENSTRUAL BLOOD CLOTTING STATUS
[0180] Menstrual blood clotting was assessing with observation and reported as yes (clotted) and no (non-clotted) over time series. As Fig. 3 illustrated, dilution with normal saline can avoid clotting of menstrual blood at room temperature. Blood only sample at room temperature becomes completely clotted. Thus, adding normal saline can be used process menstrual blood at room temperature (Fig. 3) . Even though the second sample result also showed that saline has a role to avoid menstrual blood, some inconsistent result was seen (Fig. 4) . This discrepancy might be due to 1) the day of menstrual blood collection is different, which is day 3 for the latter sample, 2) the second sample had clotting at initial during collection. As a result, we arranged sample 3 to investigate the discrepancy between sample 1 and sample 2. The result shows that normal saline can avoid menstrual blood clotting in both 4℃ and room temperature for more than 11 hours and about 27 hours with slight clot (approximately 5-10%) (Fig. 5) .
[0181] It should be understood that the examples and embodiments described herein are for illustrative purposes only and that various modifications or changes in light thereof will be suggested to persons skilled in the art and are to be included within the spirit and purview of this application and the scope of the appended claims. In addition, any elements or limitations of any invention or embodiment thereof disclosed herein can be combined with any and / or all other elements or limitations (individually or in any combination) or any other invention or embodiment thereof disclosed herein, and all such combinations are contemplated with the scope of the invention without limitation thereto.
[0182] REFERENCES
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Claims
1.A method of analyzing complete blood count and components, the method comprising:(A) obtaining a menstrual blood sample;optionally, diluting the menstrual blood sample with normal saline; anddetermining complete blood count and differential morphology of each component of the menstrual blood sample; and / or(B) obtaining a menstrual blood sample;diluting the menstrual blood sample with normal saline;optionally, storing the diluted sample for a period of time at room temperature, 4℃, or any temperature therebetween;mixing the menstrual blood sample with a staining solution; anddetermining cell viability of the stained sample.2.The method of claim 1, wherein the complete blood count comprises counts of red blood cells, white blood cells, and platelets with differential indices.3.The method of claim 1, wherein endometrial cells are identified from the menstrual blood sample.4.The method of claim 3, wherein endometrial cells comprise epithelial cells, stromal cells, immune cells, endothelial cells, progenitor cells, stem cells, or any combination thereof.5.The method of claim 1, whereinthe normal saline comprises 0.9%NaCl.6.The method of claim 1, wherein the normal saline is PBS.7.The method of claim 1, wherein the staining solution comprises acridine orange (AO) and propidium iodide (PI) .8.A method for slowing down / reducing coagulation of menstrual blood, the method comprising collecting a menstrual blood sample from a subject; and adding a collection medium in the menstrual blood sample to slow down / reduce coagulation of menstrual blood in the sample.9.The method of claim 8, wherein the subject is a human.10.The method of claim 8, wherein the collection medium is a normal saline.11.The method of claim 10, wherein the normal saline comprises 0.9 %NaCl.12.The method of claim 8, wherein the step of adding the collection medium in the menstrual blood sample is carried out immediately after collecting the menstrual blood sample.13.The method of claim 8, wherein the collection medium is added at a collection medium to menstrual blood ratio of 0: 1, 1: 1, 1: 3, or 3: 1.14.The method of claim 8, further comprising evaluating the status of menstrual blood clotting.15.The method of claim 8, further comprising evaluating cell viability in the menstrual blood sample.