Systems for transiently dynamic flow cytometer analysis

Abstract

A flow cytometry apparatus and methods to process information incident to particles or cells entrained in a sheath fluid stream allowing assessment, differentiation, assignment, and separation of such particles or cells even at high rates of speed. A first signal processor individually or in combination with at least one additional signal processor for applying compensation transformation on data from a signal. Compensation transformation can involve complex operations on data from at least one signal to compensate for one or numerous operating parameters. Compensated parameters can be returned to the first signal processor for provide information upon which to define and differentiate particles from one another.

Description

[0001] This application is a continuation of U.S. application Ser. No. 10 / 111,026 filed Apr. 18, 2002, which was the United States National Stage of International Application No. PCT / US00 / 41372 filed Oct. 20, 2000, which claims the benefit of U.S. Provisional Application 60 / 160,719, filed Oct. 21, 1999, each hereby incorporated by reference.[0002] This application makes reference to a Computer Program Listing Appendix submitted on two compact discs (which includes one duplicate copy), having the file name, “computerprogram.doc” containing 48 KB, all of which is hereby incorporated by reference herein. The compact discs were created on Mar. 30, 2006. I. TECHNICAL FIELD [0003] Specifically, flow cytometry apparatus and methods to process information incident to particles or cells entrained in a sheath fluid stream allowing assessment, differentiation, assignment, and separation of such particles or cells even at high rates of speed. II. BACKGROUND [0004] Flow cytometry is a field whic...

AI Technical Summary

Benefits of technology

[0017] Another broad object of an embodiment of the invention can be to perform compensation transformation on the original signal to provide compensated parameters. One aspect of this object can be to apply compensation transformation to processed data from a first signal incident to a first occurrence and to then apply compensation transformation to processed data from at least one additional signal incident to one or more occurrences to compensate a parameter(s) shared by the first occurrence and by at least one additional occurrence. A second aspect of this object can be compensation of parameter(s) that share characteristic(s) so that “cross talk” can be eliminated or minimized. Elimination or minimization of cross talk provides an increased ability to differentiate a first occurrence from a second or more occurrence(s). Differentiated occurrences may then be assigned to a class, separated, and collected.

[0018] Another object of an embodiment of the invention is to provide hardware or software infrastructure to allocate, align, or coordinate data generated from the above-mentioned original signals. One aspect of this object can be to provide multiple signal processors that can operate in parallel to increase the capacity to process signal data. The instant invention can utilize at least two but could utilize many parallel signal processors. The parallel signal processors could be stand aside hardware, or hardware that can coupled together via ether-net or Internet connections. A second aspect of this object of the invention can be to allocate different functions to the various parallel signal processors so as to optimize processing speed. A third aspect of this object of the invention can be to use linear assemblers and register usage to enhance parallel operation of and to coordinate the specialized functions performed by at least two signal processors. A fourth aspect of this object can be to provide software which optimizes the use of parallel processing of digital code. A fifth aspect of this object of the invention can be to apply symmetry reduction to serial transformation operations to reduce processing execution time.

[0024] Another object of an embodiment of the invention can be to provide cross beam time alignment in order to perform enhanced compensation between a pair of parameters. One aspect of this object can be to reduce the apparent inter-beam transition time to not more than 1 part in 3000 or to a compensated beam to beam “time jitter” of not more than one nanosecond, which appears to be beyond the practical capability of analog circuit design.

[0025] Another object of an embodiment of the invention can be to provide digital error compensation. Digital subtraction is attractive because it avoids the problems of signal alignment, however, major digitalization errors can occur. For example, when bright signals are compensated over a large dynamic range digitized errors, which can be visually discemable as a picket-fence coarseness of the compensated population, can occur. Digital error compensation can minimize these errors and hence improve the quality of the digital information.

[0027] Another object of an embodiment of the invention can be to provide off-loaded binning. The characteristics of, for example, populations of particles can be stored in the memory of an additional signal processor using binning transformations. The statistical characterization of these populations, such as mean, standard deviation, skewness and separation can be sent to a separate processor, thus off-loading this task and hence increasing the performance of the first processor and the separate processor.

Problems solved by technology

Unfortunately, variation in equipment operation, sheath fluid stream dynamics, or observed particle characteristics still exists and are exacerbated by increasing the speed at which entrained substances are carried in the jet.

Some of the practical problems which have also been recognized is the fact that only a limited amount of space and time exists within which to conduct sensing and analysis.

As can be understood, a substantial problem can be that the data generated from an occurrence must be sensed and reacted upon in an extremely short period of time.

The challenge for this unique flow cytometry situation is that original or raw signal data can be sub-optimal and even unusable.

This processing can be complex and can require more processing speed and power than is available not just with typical commercial systems, but even with today's highest-speed computer systems.

Further, as the desire for higher processing frequencies is pursued, problems can be compounded.

To some degree, these expectations have been so prevalent that quality control, good manufacturing practices, regulatory approval, and other concerns have been set aside, diminished, or even compromised.

Another significant problem associated with conventional analysis and compensation of variables in flow cytometry can be the preservation of original signal data from an occurrence incident to the fluid stream prior to subsequent processing steps.

It may not have been possible to preserve or store original signal data until now due to the short amount of time in which to analyze or compensate the original signal.

Yet another problem with conventional analysis may be the inability to process high speed serial occurrences, to compensate multiple parameters, to perform complex operations, to provide transformation compensation of original data, or to apply compensated parameters.

Conventional analysis can be limited by the amount of information that can be processed and returned in between serial events which can occur at a rates of at least 10,000 per second.

Conventional flow cytometer signal processors, often because they are analog, are not capable of dealing with large amounts of signal information, cannot perform operations on low quality signal information, cannot practically accomplish complex transformation operations (such as those which use algebraic expressions or structure), or they perform only reflexive feed back operations rather than serial or multi-variant analysis followed by subsequent parameter compensation.

In part, conventional infrastructure may not deal with how the streams of information are allocated, aligned, and coordinated.

As such, it can become increasingly difficult to synchronize various aspects of flow cytometer operation as the number of feed back loops increases.

Moreover, these feed back loops may be completely uncoupled.

A third aspect of this inability may be lack of symmetry reduction in the application of transformed data.

The lack of symmetry reduction or the inability to apply symmetry reduction to analysis terms may increase execution time.

As mentioned above, there has been a long felt but unsatisfied need for apparatus and methods which permit complex signal transformation, and use of compensated parameters resulting from complex signal transformation, real time analysis using compensated parameters, or storage of original signal data generated incident to the fluid stream, instrument variance, or environmental variance.

This may have been the result of the fact that those skilled in the art did not truly appreciate the nature of the problem or it may have been the result of the fact that those skilled in the art were misled by some of the presumptions and assumptions with respect to the type of systems which could be considered.

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