Test Details: Lymphocyte subset enumeration by flow cytometry gives an important information for diagnosis and monitoring of a variety of conditions affecting the immune system. CD4 T-cell subset analysis is done in case of AIDS patient, opportunistic infection in stem cell transplant patient. CD8 T cells subset analysis is done in case of individuals with EBV or CMV infection. Also a part of lymphocyte subset analysis in in patients of acute leukaemia or CLPD . Also done in post transplant individuals. NK cells are frequently involved in the outcome of important clinical interventions that are frequently monitored by multi colour flow cytometry such as transplantation or immunotherapy.