Antibody spectrum against the viral transactivator protein in patients with human immunodeficiency virus type 1 infection and Kaposi's sarcoma.
We analyzed patterns of antibody response to recombinant transactivator protein (human Immunodeficiency virus type 1 [HIV-1] tat) in serum samples from HIV-1-negative subjects (n = 60), HIV-1-infected asymptomatic patients (n = 20), HIV-1-infected patients with Kaposi's sarcoma (n = 25), and patients with Kaposi's sarcoma without HIV-1 infection. None of the healthy subjects possessed anti-tat immunoglobulin G (IgG) in their serum. All asymptomatic patients with HIV-1 infection were anti-tat IgG-positive. Epitope mapping revealed that these sera had anti-tat IgG to all the functional domains of tat protein. Histochemical studies on lymph nodes from five asymptomatic HIV-1-infected patients showed that, in all cases, tat-positive cells were present within the germinal center at the stage of follicular fragmentation containing immunoblasts and small lymphocytes. Of the 25 HIV-1-infected patients with Kaposi's sarcoma, 4 were anti-tat IgG-positive; however, the epitope analysis revealed that IgG to functional domains of tat protein--in particular to transactivating response element (TAR)-binding site--were absent. All patients with Kaposi's sarcoma without HIV-1 infection were anti-tat IgG-negative. Presence or absence of anti-tat IgG and a prevalence of different antibody profiles in different groups of patients indicated the pathophysiologic role of tat protein. Thus, a passive immunization with anti-tat IgG could be a useful strategy to influence the pathophysiologic state of the disease.
Demirhan
I
I
Gustav-Embden Center of Biological Chemistry, Department of Molecular Biology, Frankfurt University Medical School, Germany.
Chandra
A
A
Mueller
F
F
Mueller
H
H
Biberfeld
P
P
Hasselmayer
O
O
Chandra
P
P
D000914:Antibodies, Viral / Q000097:blood / Q000276:immunology*; D017209:Apoptosis; D018604:Epitope Mapping; D015696:Gene Products, tat / Q000032:analysis / Q000276:immunology*; D018858:Germinal Center / Q000276:immunology / Q000473:pathology; D015658:HIV Infections / Q000097:blood* / Q000150:complications / Q000473:pathology; D015497:HIV-1; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood / Q000276:immunology*; D008198:Lymph Nodes / Q000276:immunology; D012514:Sarcoma, Kaposi / Q000097:blood* / Q000209:etiology; D054322:tat Gene Products, Human Immunodeficiency Virus
D000914:Antibodies, Viral; D015696:Gene Products, tat; D007074:Immunoglobulin G; D054322:tat Gene Products, Human Immunodeficiency Virus