Comparison of a lysed whole blood method to purified cell preparations for lymphocyte immunophenotyping: differences between healthy controls and HIV-positive specimens.

Although the majority of clinical laboratories now use a lysed whole blood (LWB) method for routine immunophenotyping, researchers wishing to perform other types of studies with lymphocytes from HIV+ patients may still need to use purified cell preparations, such as peripheral blood mononuclear cells (PBMC). A comparison study of the two methods was performed, using peripheral blood specimens from normal donors and from patients infected with the human immunodeficiency virus (HIV+). Reproducibility studies and several types of holding studies (both before and after specimen processing) were also performed. The results suggest that the two different methods of sample preparation have different effects upon abnormal patient specimens than those observed in healthy controls. Immunophenotyping results derived from the two different methods cannot be considered equivalent for the purposes of quantitating the presence of a particular type of cell.