We have previously reported that the mechanisms of neuromyopathic
damage induced by Trypanosoma cruzi are mediated
by T cells and are parasite-strain dependent. In the present
study our aim was to determine whether the humoral response
against muscle and nervous system is also parasite-strain dependent. Of
the
sera from mice infected with RA and CA-I
T. cruzi strains, 93% reacted against antigens of the nervous
system (sciatic nerve, spinal cord and brain). No differences
in the ability to recognize heart antigens were found between RA (48%)
and CA-I (63%) antisera. Reactivity against
skeletal muscle was only relevant in anti-CA-I sera at 270 days post-infection.
Each of the antisera assayed in Western
blots developed a particular antigenic pattern, but 3 antigens in the nervous
system of molecular weight 48, 60 and 70 kDa
were detected by 42, 28 and 23% of the sera, respectively. On the other
hand,
deposits of IgG were observed at the
interstitial matrix in sciatic nerve and as endomisial and sarcolemmal
patterns
in skeletal muscle by IFAT for both RA and
CA-I antisera. Absorption of sera with parasite antigens did not abolish
the
autoreactivity. Our results suggest that major
serum autoreactivity from T. cruzi-infected mice is not parasite-strain
dependent and does not arise from molecular mimicry.