Abstract:
A flow cytometer containg a device for sampling cellular material within a body, comprising. The flow cytometer is adapted to mark cells within bodily fluid with a marker to produce marked cells, to analyze the marked cells, to sort the cells within the bodily fluid to produce sorted cells, and to maintain the sorted cells cells in a viable state.

Description:
CROSS-REFERENCE TO RELATED PATENT APPLICATIONS  
       [0001]    This application is a continuation-in-part of applicants&#39; copending patent applications U.S. Ser. Nos. 09/852,876 (filed on May 10, 2001) and 09/850,250 (filed on May 7, 2001). 
     
    
     
       FIELD OF THE INVENTION  
         [0002]    A flow cytometer adapted to both detect and treat mammalian cells, containing means for affixing a label to cellular material and thereafter removing such label.  
         BACKGROUND OF THE INVENTION  
         [0003]    Flow cytometers are well known to those skilled in the art. By way of illustration and not limitation, one may refer to, e.g., U.S. Pat. Nos. 6,198,110, 6,197,744, 6,197,593, 6,197,540, 6,197,539, and the like.  
           [0004]    Most of the prior art flow cytometers are relatively large and unwieldy and, thus, cannot readily accompany a patient in his everyday endeavors. Furthermore, most prior art flow cytometers are not adapted to sample cellular material directly; the analyte generally used with these prior art machines must be extracted and prepared in vitro from a cellular source.  
           [0005]    It is an object of this invention to provide a flow cytometer which is portable, which can be affixed to the body of a patient, which can directly sample cellular material, and which can treat cellular material.  
           [0006]    It is another object of this invention to provide a flow cytometer which can be used therapeutically as well as diagnostically.  
         SUMMARY OF THE INVENTION  
         [0007]    In accordance with this invention, there is provided a flow cytometer which comprises means for sampling cellular material, a means for marking cells within said bodily fluid with a marker to produce marked cells, means for analyzing the cellular material, means for removing such marker from the marked cells, means for sorting the cellular material, means for modifying a portion of the cellular material, and means for maintaining a portion of the cellular material which has been analyzed in a viable state. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0008]    The invention will be described by reference to the specification and to the following drawings, in which like numerals refer to like elements, and in which:  
         [0009]    [0009]FIG. 1 is a flow diagram of one preferred process of the invention;  
         [0010]    [0010]FIG. 2 is a schematic of one preferred assembly of the invention for sampling, wherein the assembly is comprised of a flow cytometer;  
         [0011]    [0011]FIGS. 3A, 3B, and  3 C schematically illustrate the actions of the pump of the assembly depicted in FIG. 2;  
         [0012]    [0012]FIG. 4 is a schematic diagram of one preferred means for preparing a bodily fluid for analysis; .  
         [0013]    [0013]FIG. 5 is a schematic of the detection/treatment system of the flow cytometer;  
         [0014]    [0014]FIG. 6 is a schematic of the flow cytometer assembly in relation to the location of bodily fluids;  
         [0015]    [0015]FIG. 7 is a schematic of one preferred means for maintaining a viable bodily fluid;  
         [0016]    [0016]FIG. 8 is a schematic of a flow cytometer disposed within a living body;  
         [0017]    [0017]FIG. 9 is a schematic of a flow cytometer disposed outside of a living body;  
         [0018]    [0018]FIG. 10 is a block diagram of another preferred process of this invention. 
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0019]    [0019]FIG. 1 is a flow diagram of one preferred process  10  for analyzing, treating, and maintaining certain bodily fluids.  
         [0020]    Sampling  
         [0021]    In step  12  of the process, the bodily fluids are sampled. One may use any conventional means for sampling the body fluids. The body fluids which are typically sampled include, e.g., blood, lymph, spinal fluid, bone marrow, and the like.  
         [0022]    In one embodiment, the body fluids are sampled by means of the sampling system described in U.S. Pat. No. 6,159,164, the entire disclosure of which is hereby incorporated by reference into this specification. The system of this patent samples a body fluid through a tube attached to a patient&#39;s body; and the system is operable buy a user having a hand, including a palm, a thumb, and at least a first finger and a second finger. The system comprises a fluid sampling site connected to the tube; means for receiving the tube; means for forming a chamber; means for selectively increasing the size of the chamber to a maximum volume and for decreasing the size of the chamber to a minimum volume, the means for increasing and decreasing the size of the chamber being operable by moving the first and second fingers or the thumb in a flexion movement toward the palm to achieve the maximum volume of the chamber, the means for increasing and decreasing the size of the chamber also being operable by moving the first and second fingers or the thumb in a flexion movement toward the palm to achieve the minimum volume of the chamber such that the same motion of the user&#39;s first and second fingers can selectively accomplish the maximum volume to aspirate fluid from the patient&#39;s body to the fluid sampling site or accomplish the minimum volume to expel the fluid into the patient&#39;s body.  
         [0023]    [0023]FIGS. 2 and 3 indicate another sampling assembly which may be used. FIG. 2 outlines the pump&#39;s bodily location and FIG. 3 details the pumping action. Referring to FIGS. 2 and 3, a patient has disposed within her body, beneath her diaphragm  16 , a pump  18  which is actuated by the movement of diaphragm  16  in the direction of arrows  19  and  20 .  
         [0024]    Referring to FIG. 3, the pump  18  has a deformable and elastic casing  22 . When casing  22  is compressed between diaphragm  16  and abdominal wall  24 , its interior volume will decrease, and fluid disposed within pump  18  will be discharged through line  26  to flow cytometer  44 .  
         [0025]    The pump  18  comprises one way flow valve  30 , which allows flow only in the direction of arrow  32 ; and it also comprises one way flow valve  34 , which only allows flow in the direction of arrow  36 . Thus, when casing  22  is compressed, fluid only may flow through line  26 ; when the compressed casing  22  is allowed to expand to its original shape (when the diaphragm  16  relaxes), the fluid may flow only through line  38 .  
         [0026]    Although the pump  18  is shown disposed beneath the patient&#39;s diaphragm  16 , it will be apparent that such pump  18  may be disposed beneath or nearby other parts of a body which expand and contract. Thus, by way of illustration and not limitation, the pump  18  may be positioned between lung and ribcage, between muscle and bone, between a heart and a sternum, and the like.  
         [0027]    Referring again to FIG. 2, it will be apparent that, every time the diaphragm  16  expands and thereafter contracts, fluid will be withdrawn from blood vessel via line  38  into pump  18 ; and the fluid within such pump  18  will be fed to flow cytometer  44  via line  26  upon the next expansion of the diaphragm  16 . This is one preferred means of sampling the blood in blood vessel  40 , and it operates continuously with the movement of diaphragm  16 .  
         [0028]    [0028]FIGS. 3A, 3B, and  3 C illustrate the operation of pump  18  in its intake phase (FIG. 3A), its expulsion phase (FIG. 3B), and its subsequent intake phase (FIG. 3C). The pump  18  is compressed when the diaphragm  16  moves in the direction of arrow  20 ; and it is allowed to return to its non-compressed state when the diaphragm  16  moves in the direction of arrow  19 .  
         [0029]    In another embodiment, not shown, the pump  18  is replaced by a piezoelectric or electrostrictive assembly (not shown) which, upon pressure being applied to it, produces a difference of potential sufficient to actuate a pump to which it is electrically connected.  
         [0030]    Sample Preparation  
         [0031]    Referring again to FIG. 1, in step  42  of the process, the bodily fluid which has been sampled is then prepared for analysis. One may use any method for enumerating and distinguishing between fluid cell populations in a bodily sample. Thus, by way of illustration and not limitation, one may use the method described in U.S. Pat. No.  
         [0032]    [0032] 6 , 197 , 593 , the entire disclosure of which is hereby incorporated by reference into this specificaiton.  
         [0033]    In the first step of the process of U.S. Pat. No. 6,197,593, a biological sample is contacted with two or more blood cell populations with a selective nucleic acid specific blocking agent to form a sample mixture. The sample mixture is then contacted with a cell membrane permeant, red-excited dye without significantly disrupting cellular integrity of the cells to form a dyed sample mixture. The dyed sample mixture is excited with light in a single red wavelength; and, thereafter, fluorescence emitted from different cell populations in the dyed sample mixture are measured, wherein the fluorescence emitted from one blood cell population is distinguishable from the fluorescence emitted from another blood cell population.  
         [0034]    Referring to FIG. 4, the appropriate dye(s) or other markers are fed to reservoir  70  by line  72  and, in response to one or more signals from controller  64 , is fed into injector  74  and thence into line  26 , where the dye(s) mix with the fluid disposed within such line  26  and selectively mark them.  
         [0035]    After the marked bodily fluid has been analyzed and, optionally, treated, and prior to the time it is returned via line  50  or  52  to either the body or to a reservoir, the marker (dye) may be removed from the fluid by conventional means. Thus, by way of illustration and not limitation, the marker may be removed by means of an adsorption column  78  and/or by other adsorption means. Thus, e.g., the dye may be removed by other means, including chemical means. By way of illustration and not limitation, processes for stripping dyes or decolorizing various materials are known in the art. For example, U.S. Pat. No. 4,227,881 discloses a process for stripping dyes from textile fabric which includes heating an aqueous solution of an ammonium salt, a sulfite salt and an organic sulfonate to at least 140.degree. F. (60.degree. C.) and adding the dyed fabric to the heated solution while maintaining the temperature of the solution. U.S. Pat. No. 4,783,193 discloses a process for stripping color from synthetic polymer products by contacting the colored polymer with a chemical system.  
         [0036]    It will be apparent that one can use one of several different physical and/or chemical means of removing the dye/marker from the bodily fluid; the aforementioned description is illustrative and not limitative. Regardless of which means are used, a purified bodily fluid is returned via line  50 / 52  to either the body or a reservoir.  
         [0037]    During the purification process, additional material needed for such process may be charged via line  80 , and/or dye and/or other waste material may be removed via line  80 .  
         [0038]    Referring again to FIG. 4, the reservoir  70  may contain one or more markers, and/or it may contain diluent to preferably dilute the bodily fluids so that preferably only one cell passes by any particular point in flow chamber  76  at any one time. As will be apparent, this “laminar flow condition” facilitates the analyses of the bodily fluid by optical means.  
         [0039]    Analysis  
         [0040]    Referring again to FIG. 4, the selectively marked bodily fluid(s) are then funneled into the flow chamber  76  of the cytometer  44 , wherein they are subjected to analysis by conventional optical means. Referring again to FIG. 1, in step  82  of the process the marked bodily fluid is analyzed. One may conduct, e.g., flow cytometeric analyses in accordance with the procedures described in the patents listed elsewhere in this specification; and one may use the devices disclosed in such patents for such analyses.  
         [0041]    One such analytical device is illustrated schematically in FIG. 5. For the sake of simplicity of representation, unnecessary detail has been omitted from FIG. 5. Referring to FIG. 5, and in the embodiment depicted therein, a light source  84  is caused to focus on flow chamber  76 . The amount of light transmitted through flow chamber  76  will vary with the properties of the bodily fluid within such chamber; see, e.g., U.S. Pat. Nos. 6,197,756, 6,197,593, 6,197,583, 6,197,582, 6,197,568, 6,197,540, and the like. The entire disclosure of each of these U.S. patents is hereby incorporated by reference into this specification.  
         [0042]    Data Collection  
         [0043]    Referring to FIG. 5, the light transmitted through flow chamber  76  is detected by detector  86  which may, e.g., be a photodetector. Data is fed from detector  86  to controller  88 .  
         [0044]    Controller  88  is equipped with a database indicating the properties of normal bodily fluids. The property of any particular bodily fluid being analyzed can be compared with this database to determine whether they correlate. A lack of correlation may indicate a disease state, which can be thereafter treated by the cytometer  44 .  
         [0045]    Referring again to FIG. 1, in step  90  data is collected from the analysis conducted in controller  88 . Historical data may also be fed to the data collection device, either before, during, or after the analysis  82  of the bodily fluid. The collection of data in step  90 , and it use, may be done in accordance with U.S. Pat. No. 6,197,593, the entire disclosure of which is hereby incorporated by reference into this specification.  
         [0046]    Data from data collection step  90  may be added to from external sources. Alternatively, data from data collection step  90  may be exported to one or more external devices.  
         [0047]    In one embodiment, not shown, when analysis step  82  and data collection step  90  indicate the presence of a dangerous abnormal condition within the bodily fluid, an external alarm is activated to warn the patient. When analysis  82  of the bodily fluid indicates that it is abnormal, the bodily fluid may be charged via line  92  to treatment step  94 . As is indicated in FIG. 5, this treatment step  94  may occur in line within the flow chamber  76 .  
         [0048]    Treatment  
         [0049]    Referring again to FIG. 5, injector  96  is operatively connected to both detector  86  and controller  88  and, in response to signals therefrom, feeds energy and/or material to the bodily fluid to treat it.  
         [0050]    One may feed radiation  98  to the bodily fluid to treat it. Thus, e.g., one may cause ultraviolet radiation to impact flow chamber  76  and to kill cancerous cell(s) disposed within such flow chamber  76 . Thus, e.g., one may use electrical discharge  100  by means such as, e.g., electroporation. Thus, e.g., one may use magnetic fields  102 . Thus, e.g., one may use sound particles and rays  104 . Alternatively, or additionally, one may feed material via line  106  into flow chamber  76  which is adapted to kill or modify the abnormal cell(s).  
         [0051]    One may use any of the materials commonly used to kill or modify cells. Thus, by way of illustration and not limitation, one may use gene vectors, viral particles, antibodies, chemotherapeutic agents, etc. Thus, e.g., one may do selective gene therapy on any particular cell.  
         [0052]    To the extent, if any, there is a need to replenish material within injector  96 , such material may be fed to injector  96  via line  115  from reservoir  116 .  
         [0053]    When it is desired to cause a particular cell to remain at a particular location for any period of time, the controller  64  can cause the close valves  112  and  114  so that fluid disposed between such valves cannot flow.  
         [0054]    Because the flow cytometer  44  is capable of detecting one cell at a time, any abnormal cell detected at point  108  may be treated at point  110 , e.g., the controller  88  determining precisely where such particular cell is at any point in time.  
         [0055]    Return  
         [0056]    As is illustrated in FIG. 1, and in step  122 , the cells or bodily fluid treated in step  94  may be returned to the body in step  122 . In the preferred embodiment depicted in FIG. 6, body fluids which have been analyzed by cytometer  44  may be fed via line  50  to vessel  41 , which may be the same or different from the blood vessel  40 , from which the bodily fluid was sampled. Alternatively, or additionally, such analyzed bodily fluids may be fed via line  52  to reservoir  54  which, in the embodiment depicted, is disposed in a blood vessel  56 .  
         [0057]    Sorting  
         [0058]    Referring again to FIG. 1, the cells analyzed in step  82  may be sorted in sorting step  118  according to criteria detected by the detector  86  and analyzed by controller  88 . In this sorting step, one may selectively segregate and collect certain cells within the bodily fluid. One may use conventional flow cytometer sorters in this step; see, e.g., U.S. Pat. Nos. 5,985,216 and 5,998,212, the entire disclosure of each of which is hereby incorporated by reference into this specification.  
         [0059]    In one embodiment, stem cells are sorted from the bodily fluid. The identification and separation of such stem cells may be conducted by conventional means such as, e.g., the means disclosed in U.S. Pat. No. 5,665,557, the entire disclosure of which is hereby incorporated by reference into this specification. In the process of this patent, for epitope mapping studies, quintuplicate aliquots of KGla cells (0.5 — 1.times.10.sup.6/analysis) were incubated for 30 min on ice with either 5ul 8A3, 7D1, 7C5 or 8A1. 2ul biotinylated conjugates of 8A3, 7D1, 7C5 or 8A1 were then added to each of the 4 sets of the above samples (i.e. 16 samples total for this experiment) for a further 30 min on ice. Cells were then washed twice in cold phosphate buffered saline by centrifugation and incubated with cychrome-conjugated streptavidin for a final 30 min on ice. Stained cells were then analyzed by flow cytometry using a FACScan (Becton Dickinson Instrument Systems (BDIS)  
         [0060]    The stem cells sorted in step  118  may be collected and thereafter used for many different purposes.  
         [0061]    Maintenance  
         [0062]    [0062]FIG. 7 is a schematic of a means for maintaining bodily fluid (and/or a portion thereof) in maintenance step  120 . Referring to FIG. 7, some or all of the cells which have been sorted in sorter  118  may be passed via line  52  to reservoir  54 . In one embodiment, not shown, sorter  118  is bypassed and bodily fluid is directly passed into reservoir  54 .  
         [0063]    In the embodiment depicted in FIG. 7, reservoir  54  is disposed within blood vessel  56 , and which is composed of porous material. In another embodiment, not shown, reservoir  54  may be disposed adjacent to a blood vessel, and/or be disposed adjacent to the intestines. This allows all necessary nutrients and supplies to be available to the retained cells. It also allows for waste products to be removed from reservoir  54 . The porous material has a pore size that allows cells to remain within reservoir  54 , but which allows nutrients and waste products to diffuse freely.  
         [0064]    Removal  
         [0065]    Referring to FIG. 7, one may remove some or all of the sorted material in step  122  and maintained in reservoir  54  by means, e.g., of syringe  60  and line  61 . One may also withdraw fluid from reservoir  54  into blood vessel  56  by means of line  58 .  
         [0066]    Location  
         [0067]    The flow cytometer  44  may be disposed either within or without the patient&#39;s body. Referring to FIG. 8, and in the preferred embodiment depicted therein, it will be seen that a flow cytometer  44  is disposed in a patient&#39;s body. In the embodiment depicted in FIG. 8, the flow cytometer  44  is disposed beneath a patient&#39;s skin, in the abdominal cavity. The flow cytometer  44  may be implanted within the patient&#39;s body by conventional means. Thus, by way of illustration and not limitation, one may implant flow cytometer  44  by the method disclosed in U.S. Pat. No. 6,198,950, the entire disclosure of which is hereby incorporated by reference into this specification. In the process of such patent, the implantable device is implanted under the skin in such a manner that the cannula projects into a blood vessel. Thus, by way of further illustration, one may use the implantation processes and/or techniques disclosed in U.S. Pat. Nos. 6,198,969, 6,198,971, 6,198,965, 6,198,952, and the like. The entire disclosure of each of these U.S. patents also is incorporated by reference into this specification.  
         [0068]    In another embodiment, illustrated in FIG. 9, flow cytometer  44  is disposed outside the body  14  rather than inside it. In this embodiment, cytometer  44  may be removably attached to the body  14  by conventional means such as, e.g., belt  48  extending around the torso of the patient. The bodily fluid is sampled from, returned to or maintained in the body via cannulae tubes  26 ,  38 ,  50  or  52 .  
         [0069]    Size  
         [0070]    The flow cytometer  44  preferably has a weight of less than 12 pounds and, more preferably, weighs less than about 6 pounds. In one embodiment, the flow cytometer  44  is made from miniaturized components and weighs less than about 3 pounds. Technologies that enable this size and weight to be achieved include low energy lasers and advanced flow chambers that allow cells to flow in a narrowly focused laminar flow stream.  
         [0071]    Power  
         [0072]    Referring to FIG. 5, the controller  64  is operatively connected to a power source  66 . In one embodiment, depicted in FIG. 4, pump  18  provides power to power source  66 . Thus, every output cycle of pump  18  provides some hydraulic pressure via line  68  to pump  66 . This hydraulic pressure is converted into electrical power by conventional means such as, e.g., piezoelectric means.  
         [0073]    In another embodiment, power source  66  is a battery. The battery may be rechargeable. Thus, in one aspect of this embodiment, the battery is recharged by electromagnetic radiation. The electromagnetic radiation may be transferred from a source disposed within the patient&#39;s body; or it may be transferred from a source external to the patient&#39;s body. Thus, e.g., an magnetic field may be produced by passing alternating current through a wire or coil, and this alternating magnetic field may be transmitted through a patient&#39;s skin into his body and coupled with an transducer, which produces alternating current from the alternating magnetic field.  
         [0074]    In another embodiment, not shown, material and/or energy is fed to power source  66  via a line (not shown), and this material and/or energy is adapted to furnish power to power source  66 . Thus, e.g., the material charged to power source  66  may undergo and/or facilitate a reaction which produces energy consumed by power source  66 .  
         [0075]    Materials  
         [0076]    Referring to FIG. 3, in one embodiment, the casing  22 , of pump  18  is made from a flexible, elastic biocompatible material. In embodiments where the flow cytometer is located subcutaneously, the flow cytometer is made from biocompatible materials such as surgical steel or encased in biocompatible materials. All cannulae and tube are preferably made from flexible, biocompatible materials. Flow chamber  76  is preferably transparent to the desired light source.  
         [0077]    Bodily Fluids  
         [0078]    In the preferred embodiment depicted in all figures, flow cytometer  44  is sampling blood. In another embodiment, not shown, the flow cytometer  44  is so disposed that it samples bodily liquids such as, e.g., lymph, bone marrow, spinal fluid, and the like. As will be apparent to those skilled in the art, the flow cytometer  44  is adapted to sample and analyze and treat unmodified bodily liquids, that is, bodily liquids occurring in their natural state within the body.  
         [0079]    Another preferred process of the invention  
         [0080]    [0080]FIG. 10 is a block diagram of a preferred process  161  which utilizes element  78  (see FIG. 4). In the first step of this process, the output of flow chamber  76  (see FIG. 4) flows to component  78  of FIG. 4 which comprises of marker/stripper  150  of FIG. 10, wherein the marker is removed from the cellular material flowing through chamber  76 . As will be apparent, the marker had first been affixed to such cellular material with injector  74  (see FIG. 4); this marker is discussed elsewhere in this specification.  
         [0081]    As is known to those skilled in the art, flow cytometry (FC) is used to detect variations in cell types and/or particles by use of fluorescent labeling and endogenous cellular optical properties. Originally flow cytometric systems were used solely to rapidly count cells. The cells were traditionally isolated from tissue or blood and labeled with fluorescent markers or antibodies conjugated with fluorescent tags. A variety of cell types have been analyzed using these methods. Cell volume and type could also be characterized by the intensity and frequency component of transmitted light. Following isolation, cells were then fed through a flow chamber of specified dimensions.  
         [0082]    Optical flow cytometer systems are based on either the detection of intrinsic scattering properties of cells (which include the cellular membrane structure, organelle concentration and structure, cytoplasmic structure, and DNA/chromatin structure) and/or of detection of emitted light from fluorescently labeled cells. The cells are usually labeled with fluorescent conjugated antibodies to cell surface receptors or cytoplasmic proteins. A source for the emission of a specified frequency of energy (i.e., a light source) is directed toward the stream of flowing cells through a narrow flow cell. It is possible to detect with a photomultiplier tube array the scattering of light through the cell (“forward light scattering”), the scattered light which is reflected orthogonal to the direction of the flow (“side light scattering”), and the fluorescence emission from fluorescently conjugated antibodies to a variety of factors within and on the cell surface.  
         [0083]    Referring again to FIG. 10, and in the embodiment depicted therein, a bodily fluid (not shown) is flowing in through chamber  76 . In one embodiment, the bodily fluid is blood, and it is caused to flow by the action of a heart. In another embodiment, the bodily fluid may be a nonhematologic fluid such as, e.g., lymph, urine, cerebrospinal fluid, and the like. In another embodiment, the bodily fluid is comprised of red blood cells and/or leukocytes and/or neutrophils and/or other cells or cellular material. Each of these components will have a different optical response to a specified optical input.  
         [0084]    The cells of the bodily fluid preferably have either endogenous optical properties, and/or they are labeled to provide optical properties. Thus, e.g., the cells may be labeled with flourescently-conjugated antibodies. Thus, e.g., in one embodiment the flow cytometer will utilize either injected fluorescent contrast or emitted light energies intrinsic to specific cells themselves. As is known to those skilled in the art, antibodies may be conjugated with polymeric dies with fluorescent emission moieties such as aminostyryl pyridinium (see, e.g., U.S. Pat. No. 5,994,143, the entire disclosure of which is hereby incorporated by reference into this specification).  
         [0085]    As is apparent, and in one preferred embodiment, the function of a flow cytometry system is to determine which, if any, of four antigens are carried by blood cells, including cell CEL. To this end, respective antibodies for the antigens are derivatized with respective fluorochromes allophycocyanin (APC), peridinin chlorophyl protein (PerCP), fluorescein isothiocyanate (FITC), and R-phycoerythrin (RPE). Reference may be had, e.g., to U.S. Pat. No. 5,682,038 for “Fluorescent-particle analyzer with timing alignment for analog pulse subtraction of fluorescent pulses arising from different excitation locations,” the entire disclosure of which is hereby incorporated by reference into this specification.  
         [0086]    By way of further illustration, U.S. Pat. No. 5,994, 143 (“Polymeric fluorophores enhanced by moieties providing a hydrophobic and conformationally restrictive microenvironment”) discloses another process for fluorescent antibody conjugation; the entire disclosure of this U.S. patent is hereby incorporated by reference into this specification. In this patent, it is disclosed that the first of two closely positioned fluorophores may be excited by light of a given wavelength. Then, instead of emitting light of a longer wavelength, the excited fluorophore transfers energy to the second fluorophore. That transferred energy excites the second fluorophore, which then emits light of an even longer wavelength than would have been emitted by the first fluorophore. An example of such an energy transfer arrangement involves phycobiliprotein-cyanine dye conjugates. Subjecting these conjugates to an about 488 nm laser light excites the phycobiliprotein. The phycobiliprotein will then, without itself irradiating, transfer energy to the cyanine fluorophore at the excitation wavelength of the cyanine, which is coincident with the emission wavelength of the phycobiliprotein, about 580 nm. Consequently, the cyanine fluorophore is thereby excited and subsequently emits light of its emission wavelength of about 680 nm. This type of energy transfer system in often referred to as a “tandem energy transfer system.” 
         [0087]    In one embodiment, not shown, dyes may be injected in a manner similar to that used to inject contrast agents for medical ultrasound techniques. See, e.g., U.S. Pat. No. 6,177,062 (“Agents and methods for enhancing contrast in ultrasound imaging”), the entire disclosure of each of which is hereby incorporated by reference into this specification. The fluorescent dyes preferably are not toxic to the living body and care must be taken in preparation of the fluorescent dyes. The combination of different wavelength fluorochromes conjugated to antibodies to different cells along with the endogenous optical properties of the cells will provide a complex multiparameter data set where differing signals from different cells will be discernable.  
         [0088]    When performing particle analysis in the body one may need to use fluorescent labels or other dyes which may be toxic to the body or to cells. In one embodiment, the bodily fluid is comprised of plasma. In one embodiment, the device  44  detects the intrinsic scattering properties of cells (which are influenced by the cellular membrane structure, organelle concentration and structure, cytoplasmic structure, and DNA/chromatin structure). Alternatively the following embodiment may be utilized.  
         [0089]    Referring again to FIG. 10, and in the preferred embodiment depicted therein, the marker or markers are removed from the bodily fluid in marker/stripper  150 . One may use conventional means from removing the marker(s) from the bodily fluid. Thus, by way of illustration and not limitation, the marker may be removed by means of an adsorption column (not shown) and/or by other adsorption means. Thus, e.g., the dye may be removed by other means, including chemical means. By way of illustration and not limitation, processes for stripping dyes or decolorizing various materials are known in the art. U.S. Pat. No. 4,783,193 discloses a process for stripping color from synthetic polymer products by contacting the colored polymer with a chemical system.  
         [0090]    In one embodiment, dye separators are used in maker/stripper  150 , and these dye separators may require additional plasma fluid which may be obtained from a plasma reservoir (not shown) which is connected to the dye separators.  
         [0091]    After the marker/stripper  150  has removed the marker(s) or otherwise rendered the fluid harmless, the removed marker(s)/dye(s) are fed via line  152  to a controllable switch valve, which can feed the marker(s)/dye(s) to one or more different locations, depending upon the nature of the marker(s)/dye(s).  
         [0092]    Thus, e.g., in one embodiment, the dyes are fed via line  80  to dye reservoir  70  (see FIIG.  4 ). Thus, e.g., in another embodiment (not shown), the dye(s)/marker(s) waste material is fed to another reservoir/holding tank (not shown), to be disposed of. In another embodiment, not shown, the dye(s)/marker(s) may be fed to the patient&#39;s bladder and/or gastrointestinal tract, depending upon the toxicity and/or degradability of the dye(s)/marker(s). The controller  64 , which includes one or more suitable sensors (see FIG. 4), controls to which destination(s) the dye(s)/marker(s) are to be sent.  
         [0093]    Referring again to FIG. 10, the purified body fluid is fed via line  156  to a fluid tester  158 , which determines the degree of purity of the body fluid. If tester  158  determines that the body fluid is not purified enough, it recycles the impure fluid via line  160  to pump  162  and thence via line  164  back into marker/stripper  150 . If the tester  158  determines that the body fluid is adequately purified, it is fed via lines  50 / 52  back into the organism (see FIG. 4).  
         [0094]    It is to be understood that the aforementioned description is illustrative only and that changes can be made in the apparatus, in the ingredients and their proportions, and in the sequence of combinations and process steps, as well as in other aspects of the invention discussed herein, without departing from the scope of the invention as defined in the following claims.