| pubmed-article:9934965 | pubmed:abstractText | Inoculation of BALB/c mice with the virulent Tulahuen (TUL) strain of T. cruzi was shown to lead to progressive and eventually lethal infections, whereas infection with an attenuated strain (TCC) resulted in a hardly noticeable experimental disease producing no tissue damage. To determine whether differences in such infection outcome are associated with a particular pattern of cytokine response, a study was undertaken to investigate the serum levels of TNF-alpha, IFN-gamma, IL-4, IL-6, and IL-10 by using an enzyme-linked immunosorbent assay. Mice from both infected groups were bled at 5, 9, 15, 22, 30 and 48 days post-infection (p.i.), with the same interval being applied for obtention of serum samples in age-matched uninfected mice, a group that yielded negative results in all cases. Infection with the TUL strain of T. cruzi was accompanied by a significant increase of TNF-alpha serum concentrations at day 5 p.i., and detectable amounts of IFN-gamma by day 15 p.i., which were exclusively recorded in this group. Serum IL-4 was mostly present in TCC mice with values at day 15 pi being statistically significant in relation to TUL-infected mice. IL-10 was firstly detected at 3 weeks after infection, and showed higher levels in the TCC group, although comparisons with TUL-infected group were not significant. At our limit of detection, no samples were found to contain IL-6 serum concentrations. Infection with virulent parasites seems to be associated with presence of Th1-type cytokines, whereas challenge with the attenuated TCC strain appears as being related to a Th2-type profile. | lld:pubmed |
