title: Interferon-gamma (IFN-gamma) can counteract the in vitro inhibitory effect of an HIV p24 immunosuppressive heptapeptide.
abstract: Previous work from our laboratory demonstrated that a synthetic heptapeptide (Ch7), corresponding to a conserved sequence of HIV core protein p24 (aa 232-238), was able to specifically abrogate antigen-induced responses in cultures of normal human peripheral blood lymphocytes (PBL). In the present study we show that Ch7 did not inhibit the induction of IFN-gamma-secreting cells nor the accumulation of IFN-gamma mRNA in antigen-stimulated cultures. However, delayed addition of recombinant human IFN-gamma to Ch7-suppressed cultures was able to restore fully the capacity to mount an antigen-specific antibody response. Thus, although the Ch7 immunosuppressive effect may not be directly related to a decreased production of IFN-gamma, an increased level of this cytokine is certainly able to counteract the negative effect of the peptide.
authors.affiliation: Department of Immunology, Istituto Superiore di Sanità, Rome, Italy.
authors.forename: A L
authors.initials: AL
authors.lastname: Luzzati
authors.forename: M
authors.initials: M
authors.lastname: Boirivant
authors.forename: E
authors.initials: E
authors.lastname: Giacomini
authors.forename: L
authors.initials: L
authors.lastname: Giordani
authors.forename: F
authors.initials: F
authors.lastname: Di Modugno
authors.forename: A
authors.initials: A
authors.lastname: Chersi
mesh_terms: D000911:Antibodies, Monoclonal / Q000096:biosynthesis; D000918:Antibody Specificity; D002478:Cells, Cultured; D016655:HIV Core Protein p24 / Q000187:drug effects* / Q000494:pharmacology; D006801:Humans; D007166:Immunosuppressive Agents / Q000037:antagonists & inhibitors* / Q000494:pharmacology*; D007371:Interferon-gamma / Q000096:biosynthesis / Q000187:drug effects / Q000494:pharmacology*; D008213:Lymphocyte Activation / Q000187:drug effects; D009842:Oligopeptides / Q000037:antagonists & inhibitors* / Q000494:pharmacology*
chemical_list: D000911:Antibodies, Monoclonal; D016655:HIV Core Protein p24; D007166:Immunosuppressive Agents; D009842:Oligopeptides; D007371:Interferon-gamma