Patent ID: 8535226

Claim:
A method for enumeration of blood cells and blood platelets to assess the degree of hematotoxicity resulting from exposure to a hazardous exogenous agent, the method comprising: providing a blood sample from a mammal exposed to a hazardous exogenous agent, the blood sample comprising erythrocytes, reticulocytes, nucleated cells, and platelets; first contacting a portion of the sample of known volume with a nucleic acid dye that has a fluorescent emission spectrum and differentially labels mature erythrocytes, reticulocytes, and leukocytes based on their nucleic acid content; second contacting the portion of the sample with a second fluorescent reagent that is responsive to mitochondrial membrane potential and thereby differentially labels healthy and damaged cells, the second fluorescent reagent having a fluorescent emission spectrum that does not substantially overlap with the fluorescent emission spectrum of the nucleic acid dye; exciting the nucleic acid dye and second fluorescent reagent with light of appropriate excitation wavelength; and measuring twice, under separate conditions, the fluorescent emission and light scatter produced by erythrocytes, reticulocytes, platelets and nucleated cells in the portion of the sample, wherein a first measurement is carried out under a first set of conditions comprising a forward light scatter threshold value set to include platelets, mature erythrocytes, immature erythrocytes, and nucleated cells; and a second measurement is carried out under a second set of conditions comprising a fluorescence threshold value set to eliminate platelets, mature erythrocytes, and immature erythrocytes, thereby restricting analyses to nucleated cells, and counting for the portion of the sample two or more endpoints selected from the group of (i) the frequency of reticulocytes, (ii) the frequency of reticulocytes with dysfunctional mitochondria, (iii) the frequency of reticulated platelets, (iv) the frequency of platelets with dysfunctional mitochondria, (v) the frequency of reticulated platelets with dysfunctional mitochondria, (vi) the frequency of lymphocytes with dysfunctional mitochondria, (vii) the frequency of neutrophils with dysfunctional mitochondria, (viii) the absolute number of lymphocytes, (ix) the absolute number of platelets, and (x) the absolute number of neutrophils, wherein the counting of two or more endpoints assesses the degree of hematotoxicity resulting from exposure to the hazardous exogenous agent.