High levels of IgA in HIV-1-perinatally-infected children. Antigen specificity and possible role of increased substance P plasma levels.

The specificity of IgA against food, inhalant, bacterial and fungine antigens as well as for HIV-1 proteins was investigated in 14 HIV-1-infected children (CDC stage P-2) and 15 controls. IgA against food- and inhalant antigens as well as against tetanus toxoid were significantly more often present in the HIV positive children than in controls. No difference between the two groups was present for IgA against Candida albicans.

[Specific IgA against multiple antigens as expression of immunologic deregulation in HIV-positive children].

B-cell dysfunction in HIV-infected children is reflected by hypergammaglobulinemia and high levels of serum IgA. Little is known about antibody specificity since only a small portion of serum IgA appears to be directed against HIV proteins. In the present study the specificity of IgA antibodies against food, inhalant, bacterial and fungi antigens were evaluated in a population of HIV infected children.

VIP restores natural killer cell activity depressed by hepatitis B surface antigen.

Vasoactive intestinal peptide (VIP) has recently been shown to bind to human lymphocytes and modulate immune functions. The ability of VIP in restoring natural killer (NK) cell activity depressed by hepatitis B surface antigen (HBsAg) has been investigated in the present research. Human lymphocytes were incubated with HBsAg and, after washing, a 4-hr cytotoxicity assay was performed.