Chemistry: molecular biology and microbiology – Measuring or testing process involving enzymes or... – Involving antigen-antibody binding – specific binding protein...
Reexamination Certificate
1999-02-18
2001-06-26
Le, Long V. (Department: 1641)
Chemistry: molecular biology and microbiology
Measuring or testing process involving enzymes or...
Involving antigen-antibody binding, specific binding protein...
C435S007200, C435S007210, C435S007920, C435S173400, C435S287100, C435S288700, C435S971000, C436S537000, C436S034000, C436S052000, C436S063000, C436S064000, C436S165000, C436S172000, C436S807000, C422S073000, C422S082050
Reexamination Certificate
active
06251615
ABSTRACT:
FIELD OF THE INVENTION
The present invention relates to methods and apparatus for analyzing cells, and particularly relates to methods and apparatus for analyzing cells suspended in a carrier solution.
BACKGROUND OF THE INVENTION
The identification and characterization of cells are important procedures in biology and medicine. Cells are the basic units of life and are deceptively complicated. Some cells remain attached to an extracellular matrix and thus form part of a larger structure. Other cells are free to move about. Examples of the former are structural cells of green plants and mammalian nerve cells and bone cells. Examples of the latter are bacteria, protozoa, and mammalian blood cells. Some cells are normally attached to extracellular matrices but may be freed by mechanical or enzymatic (proteolytic) disruption and studied, for example cells of the liver (hepatocytes).
Automated liquid flow systems have been used to analyze cells. These systems have found particular application for blood cell analysis in the form of cell counters, hematology analyzers, and flow cytometry systems. Cell counters provide counts of and size of cells in suspension. Hematology analyzers may go further by providing counts on major subsets of white blood cells, such as granulocytes and/or lymphocytes, platelets, and on subsets of red blood cells. Hematology analyzers also measure hemoglobin and additional parameters derived from these basic measured parameters or combinations of these parameters. Flow cytometry systems measure normal and abnormal cells and find application in tracking patients with abnormal cells. Flow cytometers are used in research, and more expensive versions are equipped with cell sorting capability. Flow cytometers are open ended systems requiring significant sample preparation by a trained operator. Hematology analyzers are typically dedicated flow cytometers with automated sample preparation, designed for high volume (large workload) analysis.
One of the disadvantages of flow cytometry systems is that a tiny fraction of cells that are abnormal may not be resolved from a larger population. Another disadvantage is that it is not possible to examine cells after characterization, because the cells have been lost to a waste container. To overcome this latter limitation, cell sorting systems were developed. These flow cytometry systems can direct cells that meet preset criteria to collection containers. These systems, however, are generally very expensive. Moreover, they require a priori knowledge of the cell population characteristics, which is sometimes not available. Another type of cell analysis system has been designed that prepares a blood smear and stains it for each sample so that subsequent microscopic analysis with manual examination is possible. Slide makers and slide stainers can also be separate machines. There are also automated instruments that characterize the images obtained from stained blood smears and other stained smears containing cells. These instruments are sometimes called pattern recognition machines. Generally, pattern recognition systems fail to duplicate the ability of a human technologist to discriminate between normal and abnormal cells and differentiate between different types of cells. Often they are subject to discrimination errors due to variability in staining.
Another disadvantage of flow cytometers and pattern recognition machines is that it is generally difficult and inconvenient to remove the genetic material of cells that have been characterized for further analysis (e.g., sequencing). In addition, flow cytometry systems must generally be periodically cleaned and decontaminated from exposure to hazardous biological materials. Furthermore, when cell populations are measured with automated systems, thresholds must usually be set using calibration standards and controls. Typically, this is achieved with uniformly-sized particles and cell samples that simulate the cells. The calibration procedure requires additional time and is performed on the instrument by a trained operator. Accordingly, flow cytometry instruments are expensive and labor intensive. They are usable by highly trained laboratory professionals, only. Accordingly, there remains a need for a system that can be used for the simple and convenient analysis of cells in solution.
SUMMARY OF THE INVENTION
The present invention enables convenient analysis of samples containing suspended cells for research and/or clinical use. In one embodiment, this analysis involves the capture of or delay in transit time of cells with specific surface molecules by means of affinity interactions with test surfaces. The operation of a cell analysis system according to this invention is simple, yet the number of parameters that may be measured is substantially increased over what may be achieved by conventional cell analysis systems.
One object of this invention is to provide methods and apparatus that may be used when it is desired to measure the kinetics of cell capture by test surfaces containing designated affinity molecules (receptors or ligands, antibodies or antigens) to provide a new analytical tool for research and clinical applications. With this invention, the kinetics of cell capture can be determined as a function of convective effects, such as shear forces acting on the cell, and temperature. Temperature affects cell membrane fluidity and influences bond formation with affinity molecules such as antibodies. The kinetics of dissociation of captured cells under the influence of shear forces and temperature may also be determined.
Another object is to provide a system that may be used for analyzing cell attachment to surfaces with affinity molecules by precise flow control, where this flow control may be open loop control via any of a variety of computer programs for flow rate versus time or may be closed loop control using feedback to the computer from sensors that measure cell capture events.
It is another object of this invention to provide a system that may be used for measuring a variety of different types of cells.
Another object of this invention is to provide a cell analysis system that may be used to retain cells for further analysis. This further analysis can be microscopic, genetic, or molecular in nature.
Another object is to permit cell standards and controls to be incorporated, as part of the analytical procedure, in self-contained analysis cartridges, obviating extra steps and providing a system that is usable by individuals without laboratory training.
Another object of this invention is to provide a system that may be used for functional analysis of cell interaction with surfaces containing affinity molecules, thus simulating biological functions of cell adherence to extracellular surfaces and to surfaces of other cells, and eventually measuring cell metabolic changes, such as degranulation, shape changes, and secretion of cell products.
It is a further object to provide a system that may be used for functional analysis of cells by providing surfaces that can capture cells and activate other cell functions such as cell spreading across the surface and the appearance on the cell surface of new receptors.
Yet another object of this invention is to provide a potentially convenient methodology and apparatus for researchers to affix unique affinity molecules, such as specific antibody, to surfaces contained therein so that a sample containing cells may be conveniently analyzed.
A further object is to provide a clinical cell analysis system that may be embodied so as to require minimal operator steps and can perform tests and can perform data management and data transmission functions.
Yet another object is the provision of a system that may be used to analyze all major blood cell types with a minimum of reagent additions and without requiring lysis of red blood cells in order to make measurements of other cell types.
A first aspect of the present invention is a method of analyzing cells in a carrier solution. The method comprises:
(a) introducing the carrier solution into a c
Cell Analytics, Inc.
Gabel Gailene R.
Le Long V.
Myers Bigel Sibley & Sajovec P.A.
LandOfFree
Cell analysis methods does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Cell analysis methods, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Cell analysis methods will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2523456