Abstract
Gnathostomiasis is an emerging infectious disease, in which the agent Gnathostoma binucleatum is the only species known to infect humans in Mexico. Although the humoral immune response to G. binucleatum has been analyzed previously, here we evaluated the lymphoproliferative response of peripheral blood lymphocytic cells from patients clinically diagnosed with gnathostomiasis against a crude extract of G. binucleatum using the MTT method, and compared the response to that of healthy subjects. No differences in the response to concanavalin A were found between the groups; however, the response to the crude extract was statistically higher in patients compared to healthy controls (1.188 ± 0.135, and 1.000 ± 0.045, p = 0.0004). Patients at > 6 months after diagnosis showed a higher lymphoproliferative response than the group of healthy subjects, and those at < 6 months after diagnosis (p = 0.0001, and 0.0164 respectively). These data suggest that the parasite induces non-protective immunological memory.