T cell hyperreactivity to IL-6 in chronic nonviremic HBV carriers despite normal IL-6 receptor or gp130 expression.
We previously showed that T cells from chronic nonviremic HBsAg carriers activated with immobilized OKT3 MAb are hyperreactive to monocyte accessory signals, mainly to interleukin-6 (IL-6). We have further characterized this T cell hyperreactivity using phytohemagglutinin (PHA) as the primary activating signal. PHA-stimulated T cells from nonviremic patients had a significantly higher response to addition of monocytes, monocyte supernatants, and IL-6 alone or combined with IL-1 beta when compared to controls. We examined if these effects could be mediated by a differential expression of IL-6 receptor (p80) or gp130 on resting or PHA-stimulated T cells. We found that PHA, IL-6, IL-1 beta, or IL-2 induced only small changes of the dull p80 expression on T cells. In contrast, we found a significant increase of gp130 expression on PHA-activated T cells compared to unstimulated T cells, which was down-regulated by the presence of IL-6. However, no significant differences in p80 or gp130 expression were detected between patients and controls within all the culture conditions tested. Our results confirm that IL-6 is involved in the in vitro T cell hyperreactivity of nonviremic HBV carriers and indicate that this effect is not mediated by disturbances of IL-6 receptor expression.
Institute of Immunology, Central University School of Medicine, Caracas, Venezuela.
M L
ML
Baroja
F L
FL
Sirit
H
H
Rivera
J
J
Garzaro
N E
NE
Bianco
I V
IV
Machado
D000328:Adult; D015703:Antigens, CD / Q000276:immunology*; D002353:Carrier State / Q000276:immunology*; D002455:Cell Division; D002478:Cells, Cultured; D002908:Chronic Disease; D018920:Coculture Techniques; D050822:Cytokine Receptor gp130; D016207:Cytokines / Q000276:immunology; D005260:Female; D006509:Hepatitis B / Q000276:immunology*; D006515:Hepatitis B virus / Q000276:immunology*; D006801:Humans; D015850:Interleukin-6 / Q000276:immunology*; D008297:Male; D008562:Membrane Glycoproteins / Q000276:immunology*; D008875:Middle Aged; D009000:Monocytes / Q000166:cytology / Q000276:immunology; D010835:Phytohemagglutinins / Q000494:pharmacology; D018123:Receptors, Interleukin / Q000276:immunology*; D019947:Receptors, Interleukin-6; D013601:T-Lymphocytes / Q000187:drug effects / Q000276:immunology*; D014766:Viremia
D015703:Antigens, CD; D016207:Cytokines; C494199:IL6ST protein, human; D015850:Interleukin-6; D008562:Membrane Glycoproteins; D010835:Phytohemagglutinins; D018123:Receptors, Interleukin; D019947:Receptors, Interleukin-6; D050822:Cytokine Receptor gp130