The outcome of infection with lymphatic-dwelling filarial worms is determined, in part, by the host immune response. Persons with persistent parasitemia and those with chronic manifestations of filariasis such as elephantiasis seem to express distinct, if not opposing immune responses.
To increase our understanding of the various factors that influence host susceptibility to infection and disease, we are utilizing a multidisciplinary approach to study filariasis. Antigen characterization efforts include both immunochemical methods and molecular cloning. Cytokine responses to specific parasite antigens are measured by ELISA, bioassay, and RT-PCR. Laboratory work is complemented by longitudinal field studies that are focused on monitoring parasitologic and immunologic correlates of exposure to Wuchereria bancrofti infection.
Within the context of our field studies, we are interested in understanding: 1) the influence of in utero exposure to filarial antigens on the development and expression of antifilarial immunity; 2) the relationship between anti-filarial immunity and development of lymphedema and elephantiasis; and 3) how host responses are regulated by long-term exposure to infective larvae.
With this research, we hope to increase our understanding of fundamental aspects of the host-parasite relationship. We are also studying Cryptosporidium, a protozoan parasite which has been associated with several outbreaks of severe diarrheal illness. Despite the recognition that host T cell reactivity is critical to the development of protective immunity, little is known about the precise nature of the T cell response or the antigens that elicit this response. We are examining responses to purified and cloned Cryptosporidium antigens and are using an animal model of infection to analyze the role of intraintestinal epithelial lymphocytes in controlling these parasites.
- Addiss, D.G., Beach, M.J., Streit, T.G., Lutwick, S., LeConte, F.H., Lafontant, J.G., and Lammie, P.J. (1997). “Efficacy and tolerance of combined single-dose ivermectin and albendazole for Wuchereria bancrofti microfilaremia in Haitian children.” Lancet 350:480-484.
- Moss, D.M., Bennett, S.N., Arrowood, M.J., Wahlquist, S.P., and Lammie, P.J. (1998). “Enzyme-linked immunoelectrotransfer blot analysis of a cryptosporidiosis outbreak on a U.S. Coast Guard cutter.” Am. J. Trop. Med. Hyg. 58:110-118.
- Wamae, C.N., Gatika, S.M., Roberts, J.M., and Lammie, P.J. (1998). “Wuchereriabancrofti in Kwale District, Coastal Kenya. I. Patterns of focal distribution of infection, clinical manifestations and antifilarial IgG responsiveness.” Parasitology 116:173-182. 1998.
- Lammie, P.J., Reiss, M.D., Dimock, K.A., Streit, T.G., Roberts, J.M. and Eberhard, M.L. (1998). “Longitudinal analysis of the development of filarial infection and antifilarial immunity in a cohort of Haitian children.” Am. J. Trop. Med. Hyg. 59:217-221.
- Moss, D.M., Chappell, C.L., Okhuysen, P.C., Arrowood, M.J., DuPont, H.L., Hightower, A.W. and Lammie, P.J. “The antibody response to 27-, 17- and 15-kDa Cryptosporidium antigens following experimental infection in humans.” J. Inf. Dis.