| Autor: |
Vento, S., Chen, S. -H., Giuliani-Piccari, G., O'Brien, C. J., Dal Monte, P. R., Eddleston, A. L. W. F., Howard, C. R., Williams, R. |
| Předmět: |
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| Zdroj: |
Immunology; Dec87, Vol. 62 Issue 4, p593-598, 6p |
| Abstrakt: |
Previous studies of cellular immunity in asymptomatic HBV carriers have been limited to evaluation of responses to plasma-derived HBsAg preparations. We have explored the specificity of cellular immune responses to HBV antigens in these subjects using an indirect T-lymphocyte migration inhibitory factor assay and three antigen preparations (recombinant nucleocapsid antigen (HBcAg), plasma-derived HBsAg with or without pre-S2, and Saccharomyces cerevisiae-synthesized HEsAg without pre-S2 region). T cells from 10 asymptomatic chronic HBV carriers with normal liver function tests were responsive to nucleocapside determinants (mean migration index = 0.55 ± SD 0.07) and to pre-S2-positive plasma-derived HBsAg (MI = 0.62 ± 0.05). However, none responded to HBsAg devoid of pre-S2 sequences (M1=0.98±0.04). In further experiments, T cells from three HBV carriers, cultured with six different HBsAg preparations, exhibited responsiveness only to those preparations containing significant pre-S2 activities. Our results show that T-cell immunity to nucleocapsid determinants of the virus and HBsAg in present in asymptomatic HBV carriers; the latter is restricted to antigenic preparations containing significant pre-S2 activities. Hence, T-cell immunity to pre-S determinants may not always be associated with HBV clearance. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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