Abstract: Manually overridable servo controlled valve mechanisms for controlling the flow of fluids through a flexible tube for use in a photoactivatable agent treatment system wherein photoactivatable agents, in contact with patient blood cells, are irradiated extracorporeally and then returned to the patient.

Abstract: Methods for determining the presence of large molecular weight aqueous ligands. The sample ligands are made to compete with user supplied fluorescently labeled peptides for binding sites on a ligand binding partner. Presence of aqueous ligand and binding of ligand binding partner thereto leaves the fluorescently labeled peptides free to exhibit fluorescence depolorization effects.

Abstract: Dyes are provided comprising phycobiliproteins having covalently coupled thereto a plurality of small molecular weight organic dyes under conditions permitting energy transfer mechanisms to operate therebetween. The resultant label may then be used in virtually any immunoassay format.

Abstract: Homogeneous immunoassays employing double ligand binding conjugates comprising an anti-idiotype binding partner. The anti-idiotype binding partner competes with ligand for an insolubilized ligand specific binding partner. Inhibition of binding of the conjugate to the insolubilized binding partner due to ligand binding permits the second binding partner in the conjugate to bind with insolubilized label means. Thus, detection of label is inversely related to the presence of ligand in the sample.

Abstract: Apparatus for immobilizing biological cells based on the dielectric properties of biological cells. An inhomogeneous electric field emanating from a grid point location or other contact area is created and attracts the biological cell into contact therewith. Appropriate controls over a series of grid points permits controlled inter-grid point movement of cells thereby permitting sequential testing or sorting processes to be carried out.

Abstract: A generalized cytometry instrument for measuring the kinetic properties of live cells. Cells are immobilized on a surface and their positions determined and stored in memory by a central control computer. The cells are subsequently illuminated and an optical interaction detected. By taking many measurements of many cells, each of whose position and respective data is stored permitting subsequent reexamination and determination of activity as a function of time, respectively; the kinetic properties of large populations of cells may be studied in the presence of a variety of stimulating environments. Such stimulations may arise from contact with various reagents, including antigens, mitogens and peptides as well as electrical and mechanical perturbations.

Abstract: Manually overridable servo controlled valve mechanisms for controlling the flow of fluids through a flexible tube for use in a photoactivatable reagent treatment system wherein photoactivatable reagents, in contact with patient blood cells, are irradiated extracorporeally and then retruned to the patient.

Abstract: Lysing reagents for use in flow cytometry instruments. Lysing reagents suitable for lysing red blood cells are provided thereby permitting 3-part differential counting of white blood cells. The reagents comprise a leukoprotective agent for preserving the lymphocyte cellular integrity during analysis, and buffers adjusted to provide the correct pH environment for optimal lysis and activity. Preferred embodiments will additionally incorporate non-ionic preservatives in very low concentrations.

Abstract: A preferred patient blood treatment system for the photoactivation of reagents in contact with a patient's blood employs an infusion pump for adding anti-coagulation reagent to the blood during extracorporeal operations. The infusion pump is preferably driven by a stepper motor and monitored by a periodic photo chopper employing a plurality of sensors. The spacing of the sensors and the spacing of the photo choppers work in concert to detect rotation of the stepper motor and to discriminate such from stutter or other characteristic nonrotational faults associated with stepper motors.

Abstract: Histidine-stabilized immunoglobulin preparations and a method for their manufacture are disclosed. The present invention is particularly well suited for stabilization of human gamma globulin (IgG) preparations having a relatively low protein content. Preferred stabilized human gamma globulin preparations comprise about 5 wt-% or less gamma globulin, histidine at a concentration of about 0.025M to about 0.2M, and optionally glycine at a concentration of about 0.05M to about 0.5M. The pH value of the preparations is at least 6.0 but not more than 7.0. A pH value of about 6.4 is most preferred. Conductivity of the preparations is about 2 to about 4 millisiemens at 5.degree. C., preferably about 2.5 to about 3.5 millisiemens at 5.degree. C., and most preferably about 2.7 millisiemens at 5.degree. C.

Abstract: Manually overridable servo controlled valve mechanisms for controlling the flow of fluids through a flexible tube for use in a photoactivatable reagent treatment system wherein photoactivatable reagents, in contact with patient blood cells, are irradiated extracorporeally and then returned to the patient.

Abstract: A blood flow system for processing blood has two phases of operation, an arterial phase and a venous phase. During the arterial phase, the system is filled with blood through operation of an arterial blood pump. When a predetermined blood pressure level in the system has been attained, the arterial blood pump is inactivated and a venous blood pump removes blood from the system for a given number of pump turns. By accurately monitoring both arterial and venous pumps operating cycles, ultrafiltration volume and rate may be determined.

Abstract: Methods useful for differentiating and enumerating subpopulations of particles in a sample and more particularly relates to the enumeration of leukocyte subclasses. Enumeration is accomplished by utilizing two light scatter parameters and converting these parameters to a single parameter by employing a mathematical, nonlinear transformation.

Abstract: Methods for the determination of phagocytic and killing ability of selected leukocyte subclasses based upon the use of three part differentials obtained by light scatter characteristics and gated fluorescence. Particles having multiple fluorescent labels associated therewith, one of which is sensitive to reactive oxygen, incubated with the leukocytes. Detection of the fluorescent labels permits identification of cells having phagocytic ability, as determined by presence of the non-sensitive label, and also the identification of those with killing ability as determined by the decrease in fluorescence from the sensitive label.

Abstract: A diluted whole blood sample is hydrodynamically focused to a given point. A light beam is transversely focused on the same point and the principles of dark field microscopy are utilized, detecting scattered light and thereby discriminating platelets from red blood cells based on cell volume and refractivity.

Abstract: Provided are apparatus and methods of use for extracorporeally treating a patient whereby blood is withdrawn from the patient, separated into a leukocyte enriched portion which, in contact with a photoactivatable reagent, is irradiated and all blood portions being returned to the patient. The preferred apparatus is suitably modified with appropriate tubing sets, valves, pumps, centrifuge and controlling means to perform the patient treatment in three operational phases.

Abstract: Flexible container means for the warming or cooling of fluids. A preferred embodiment, useful for the warming of plasma following cryogellation techniques prior to its return to the patient, comprises container means formed by the heat sealing of polymeric materials thereby defining a winding passageway of tapered walls whereby the container becomes air self-evacuating.

Abstract: In a system for altering cells such as by irradiating said cells when in contact with a photoactivatable reagent useful for the extracorporeal treatment of a patient's blood, a three phase method for performing the operations in a safe and efficacious manner.

Abstract: Cassette drawer assembly for receiving an irradiation cassette wherein patient blood is irradiated to photoactivate a reagent in contact therewith, said irradiated blood being returned to the patient as part of the complete treatment.

Abstract: Methods are provided for ensuring the safety of a patient undergoing extracorporeal treatment by irradiation of a photoactivatable reagent in contact with the patient's blood including simultaneous digital and analog monitoring of temperature, voltage and current sensor signals. Also provided is a control system for controlling and regulating the various components of the photophoresis patient treatment system.