Tumor necrosis factor alpha (TNF alpha) is a proinflammatory cytokine princ
ipally involved in the activation of lymphocytes in response to viral infec
tion. TNF alpha also stimulates the production of other cytokines, activate
s NK cells and potentiates cell death and/or lysis in certain models of vir
al infection. Although TNF alpha might be expected to be a protective compo
nent of an antiviral immune response, several lines of evidence suggest tha
t TN alphaF( and other virally-induced cytokines actually may contribute to
the pathogenesis of HIV infection. Based on the activation of HIV replicat
ion in response to TNF alpha, HIV appears to have evolved to take advantage
of host cytokine activation pathways. Antibodies to TNF alpha are present
in the serum of normal individuals as well as in certain autoimmune disorde
rs, and may modulate disease progression in the setting of HIV infection. W
e examined TNF alpha -specific antibodies in HIV-infected non-progressors a
nd healthy seronegatives; anti-TNF alpha antibody levels are significantly
higher in HIV seropositive slow/non-progressors (N = 120, mean = 0.24), com
pared to seronegative controls (N = 12, mean = 0.11). TNF alpha antibodies
correlated positively with viral load, (P = 0.013, r = 0.282), and CD8+ cel
l count (P = 0.03, r = 0.258), and inversely with CD4+ cell count (P = 0.00
3, r = -0.246), percent CD4+ cells (P = 0.008, r = -0.306), and CD4 :CD8 ra
tio (P = 0.033, r = - 0.251). TNF alpha antibodies also correlated positive
ly with antibodies to peptides corresponding to the CD4 binding site of gp1
60 (P = 0.001, r = 0.384), the CD4 identity region (P = 0.016, r = 0.29), t
he V3 loop (P = 0.005, r = 0.34), and the amino terminus of Tat (P = 0.001,
r = 0.395); TNF alpha antibodies also correlated positively with antibodie
s to Nef protein (P = 0.008, r = 0.302). The production of anti-TNF alpha a
ntibodies appears to be an adaptive response to HIV infection and suggests
the potential utility of modified cytokine vaccines in the treatment of HIV
infections as well as AIDS-related and unrelated autoimmune and CNS disord
ers. (C) 2801 Editions scientifiques et medicates Elsevier SAS