title: Expression of IL-10, IL-4 and interferon-gamma in unstimulated and mitogen-stimulated peripheral blood lymphocytes from HIV-seropositive patients.
abstract: Infection of immune cells with HIV induces dysregulation of cytokines which may play a vital role in HIV pathogenesis. We analysed the expression of T helper type 1 (Th1) (interferon-gamma (IFN-gamma)) and Th2 (IL-4, IL-10) type cytokines in peripheral blood lymphocytes (PBL) from HIV+ patients. The semiquantitative reverse transcriptase polymerase chain reaction (RT-PCR) analysis revealed that IFN-gamma mRNA in unstimulated PBL was significantly decreased and IL-10 mRNA was significantly upregulated in patients with < 400 CD4+ T cells/mm3 (n = 30) as compared to patients with > 400 CD4+ T cells/mm3 (n = 6) and normal controls (n = 16). In addition, IL-10 mRNA levels were inversely associated with IFN-gamma expression. Similar results were obtained by measuring IL-10 production in the supernatants of PBL cultured in vitro without stimulation by employing an enzyme immunosorbent assay (ELISA). However, the levels of IL-4 and IFN-gamma produced by unstimulated PBL were undetectable by ELISA. Mitogen stimulation of PBL revealed two groups of HIV+ individuals based on IL-10 production. PBL from one set of individuals produced low levels of IL-10 (low IL-10 producers) whereas the other group produced IL-10 comparable to that of normal controls (IL-10 producers). Production of IL-4 was significantly reduced in HIV+ individuals with < 400 CD4+ T cells/mm3 as compared to the normal controls. However, ability to produce IFN-gamma by mitogen-stimulated total PBL and CD4+ purified cells was not impaired in HIV+ individuals. These results suggest that unstimulated and mitogen-stimulated PBL of HIV+ individuals exhibit dysregulation of Th2 type cytokines which may play a role in HIV immunopathogenesis.
authors.affiliation: Department of Paediatrics, Children's Hospital of Eastern Ontario, University of Ottawa, Canada.
authors.forename: F
authors.initials: F
authors.lastname: Diaz-Mitoma
authors.forename: A
authors.initials: A
authors.lastname: Kumar
authors.forename: S
authors.initials: S
authors.lastname: Karimi
authors.forename: M
authors.initials: M
authors.lastname: Kryworuchko
authors.forename: M P
authors.initials: MP
authors.lastname: Daftarian
authors.forename: W D
authors.initials: WD
authors.lastname: Creery
authors.forename: L G
authors.initials: LG
authors.lastname: Filion
authors.forename: W
authors.initials: W
authors.lastname: Cameron
mesh_terms: D000328:Adult; D001483:Base Sequence; D006679:HIV Seropositivity / Q000276:immunology*; D006801:Humans; D007371:Interferon-gamma / Q000096:biosynthesis*; D016753:Interleukin-10 / Q000096:biosynthesis*; D015847:Interleukin-4 / Q000096:biosynthesis*; D008213:Lymphocyte Activation; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D006377:T-Lymphocytes, Helper-Inducer / Q000378:metabolism*
chemical_list: D016753:Interleukin-10; D015847:Interleukin-4; D007371:Interferon-gamma