One-round determination of seven leukocyte subsets in rhesus macaque blood by flow cytometry.

Abstract

Rhesus macaques are frequently used in biomedical research as experimental models for studying infectious diseases and for preclinical vaccination trials. The infection of these monkeys with simian immunodeficiency viruses (SIV) or simian-human immunodeficiency viruses (SHIV) reproduces the clinical and immunological characteristics of human infection by human immunodeficiency virus (HIV). Evolution of the immune response in the infected animals is generally analyzed by determining the lymphocyte subsets on blood samples using flow cytometry but requiring multiple, blood consuming, determinations. Cell subsets present in whole-blood samples were labeled with a combination of anti-human monoclonal antibodies to CD2, CD20, CD4, CD8, and CD14 coupled to FITC or PE and analyzed by flow cytometry. In one round, we obtained the precise determination of macaque blood cell composition by flow cytometry. Monocytes, granulocytes, eosinophils, B lymphocytes, helper, and cytotoxic T lymphocytes were distinguished. Results obtained correlated strongly with those obtained with conventional blood cell differential systems and with separate staining of lymphocytes. The analysis of blood from healthy rhesus macaques and SHIV-infected animals demonstrated the accuracy of the determination even in very pathological situations such as macaques with simian AIDS. Our method allows fast determination of the blood cell composition and will be particularly useful to evaluate the cell subset evolution of macaques involved in large-scale experimental trials.