CHANGES OF BLOOD CD16 CD56 (NK) AND HLA-DR/CD3-POSITIVE LYMPHOCYTE AMOUNTS IN HIV-INFECTED CHILDREN, AS RELATED TO CLINICAL PROGRESSION ANDP24-ANTIGEN P24-ANTIBODY PRESENCE/

This study describes a series of immunological investigations carried out on a group of 37 HIV-seropositive children, aged 3-4 years, in two different stages of disease defined according to the CDC classificati on; the Primary stage, an asymptomatic one, showing abnormal immune fu nction (P(1)Class, B-Subclass) and the Secondary stage, 6-8 months lat er, in which patients exhibited non-specific findings, i.e., loss of w eight, persistent generalized lymphadenopathy and hepatosplenomegaly, associated with abnormal immune function (P2-class, A-Subclass). In bo th stages, immune function was considered 'abnormal' when lymphopenia and a decrease of the CD4/CD8-cell ratio were found. The phenotypes CD 16(+)/56(+) (NK) and HLA-DR(+)/CD3(+) (T-activated?)-positive cells, w ere assesed by flow cytometry, and the following supplementary systemi c humoral markers were investigated in homologus serum samples; total HIV(gp)-antibody, HIV(p24)-antibody and p24-antigen presence. If at th e primary stage, no significant difference from to the reference value s corresponding to the age was noticed, at the secondary stage the obt ained data is presented separately in two subgroups, namely the A-subg roup characterized by the presence of total HIV(gp)-antibody, the pres ence of HIV(p24)-antibody and the absence of p24-antigenaemia, and the B-subgroup, where total HIV(gp)-antibody was present, HIV(p24)-antibo dy absent and p24-antigenaemia present. A significant decrease of CD16 (+)/56(+) (NK)-cells was found within the two subgroups. As far as HLA -DR(+) from CD3(+)-cells was concerned, only those within the B-subgro up showed a high percentage level, compared to the reference values. T he importance of the present findings, linked to immune monitoring of HIV infection among children, is discussed.