Salivary sIgA response in HIV-1 infection.
Local and systemic production of total and HIV-1 specific IgA was determined in whole saliva and serum from 45 HIV-1-infected individuals and 15 healthy controls. The antigenic domains important for sIgA and IgG binding, respectively, was investigated with epitope mapping using synthetic peptides of HIV-1 proteins. Decreased levels of total sIgA in saliva were found among patients with low CD4+ cell counts in advanced stages of acquired immunodeficiency. HIV-1 specific IgA response, predominantly directed to the envelope proteins, was found in saliva and serum also at later stages of disease. Analyses using peptide enzyme-linked immunosorbent assays (ELISA) showed that the sIgA antibody response in saliva was mainly directed to the V4 region (aa 385-409) and a more C-terminal part of the V3-region (aa 325-344) compared with the IgG response, which predominantly was directed to a more central part of the V3 loop (aa 308-325). A similar picture was seen for immunoglobulins of the two isotypes derived from serum. We have in this study shown IgA epitope-specific immune response within HIV-1 gp160, indicating that antibodies of IgA isotype may recognize somewhat different antigenic domains compared to IgG antibodies.
Skott
P
P
The Microbiology and Tumorbiology Center at Karolinska Institute, Stockholm, Sweden.
Lucht
E
E
Julander
I
I
Dillner
J
J
Björling
E
E
D000163:Acquired Immunodeficiency Syndrome / Q000145:classification / Q000150:complications / Q000276:immunology* / Q000473:pathology; D000328:Adult; D000595:Amino Acid Sequence; D000918:Antibody Specificity; D018791:CD4 Lymphocyte Count; D018604:Epitope Mapping; D015686:Gene Products, env / Q000276:immunology; D015683:Gene Products, gag / Q000276:immunology; D015483:HIV Antibodies / Q000032:analysis / Q000097:blood / Q000276:immunology*; D015497:HIV-1 / Q000276:immunology*; D006801:Humans; D018928:Immunity, Mucosal; D007071:Immunoglobulin A, Secretory / Q000032:analysis / Q000097:blood / Q000276:immunology*; D007074:Immunoglobulin G / Q000032:analysis / Q000097:blood / Q000276:immunology; D008969:Molecular Sequence Data; D009059:Mouth Diseases / Q000150:complications / Q000276:immunology / Q000473:pathology; D010446:Peptide Fragments / Q000138:chemical synthesis / Q000276:immunology; D012463:Saliva / Q000737:chemistry / Q000276:immunology*
D015686:Gene Products, env; D015683:Gene Products, gag; D015483:HIV Antibodies; D007071:Immunoglobulin A, Secretory; D007074:Immunoglobulin G; D010446:Peptide Fragments