Immunophenotypes by flow cytometry: a longitudinal study in healthy individuals

Weekly blood samples from five healthy volunteers were obtained for 13 weeks to assess the variations in the immunological phenotypes of peripheral blood lymphocytes and monocytes. Monoclonal antibodies to eleven lymphocyte and two monocyte antigens were evaluated using two-color flow cytometry. Average week-to-week differences were less than 5% for all monoclonal antibodies and combinations except for I2+, NKH-1+, MO1+, and MO2+ cells. The observed variations presumably reflected both technical variables and responses of the immune system to daily environmental insults.