Important questions remain about the immunology and epidemiology of visceral leishmaniasis. A subset of infected persons develop overwhelming disease which progresses to death if they are not treated; others have asymptomatic, self-resolving leishmanial infection. Although many factors may contribute to the outcome of leishmanial infection, cell mediated immune mechanisms are almost certainly responsible for control of the parasite and protection against reinfection. Our goal is to characterize the natural history, epidemiology and immunology of American visceral leishmaniasis in residents of rural, northeastern Brazil where L. chagasi poses a major health problem. Leishmania-specific cellular and humoral immune responses will be assessed. Emphasis will be directed toward identifying parasite antigens which stimulate leishmania-specific T helper cells at sequential times during self- resolving, asymptomatic infection and to characterizing the relationship of those antigens to parasite antigens identified by immunoblots of serum. Similar studies will be performed in patients after successful treatment of symptomatic visceral leishmaniasis.
The final aim i s to isolate human T helper cell lines and clones which are dependent on leishmanial antigen for proliferation and lymphokine production in order to characterize the antigens to which these T cells respond. Completion of the proposed studies should provide important new insights into the epidemiology and immunology of American visceral leishmaniasis and a better understanding of the leishmanial antigens that elicit T helper cell responses.

Project Start
Project End
Budget Start
Budget End
Support Year
4
Fiscal Year
1992
Total Cost
Indirect Cost
Name
University of Virginia
Department
Type
DUNS #
001910777
City
Charlottesville
State
VA
Country
United States
Zip Code
22904
Holaday, B J (2000) Role of CD8+ T cells in endogenous interleukin-10 secretion associated with visceral leishmaniasis. Mem Inst Oswaldo Cruz 95:217-20
Holaday, B J (1999) Immunotherapy for visceral leishmaniasis: ability of factors produced during anti-leishmania responses of skin test positive adults to inhibit peripheral blood mononuclear cell activities associated with visceral leishmaniasis. Mem Inst Oswaldo Cruz 94:55-66
Silva, A C; Santos-Neto, M S; Soares, A M et al. (1998) Efficacy of a glutamine-based oral rehydration solution on the electrolyte and water absorption in a rabbit model of secretory diarrhea induced by cholera toxin. J Pediatr Gastroenterol Nutr 26:513-9
Rocha, M F; Soares, A M; Flores, C A et al. (1998) Intestinal secretory factor released by macrophages stimulated with Clostridium difficile toxin A: role of interleukin 1beta. Infect Immun 66:4910-6
Rocha, M F; Maia, M E; Bezerra, L R et al. (1997) Clostridium difficile toxin A induces the release of neutrophil chemotactic factors from rat peritoneal macrophages: role of interleukin-1beta, tumor necrosis factor alpha, and leukotrienes. Infect Immun 65:2740-6
Koopmans, M P; Goosen, E S; Lima, A A et al. (1997) Association of torovirus with acute and persistent diarrhea in children. Pediatr Infect Dis J 16:504-7
Lima, A A; Silva, T M; Gifoni, A M et al. (1997) Mucosal injury and disruption of intestinal barrier function in HIV-infected individuals with and without diarrhea and cryptosporidiosis in northeast Brazil. Am J Gastroenterol 92:1861-6
Braga, L L; Lima, A A; Sears, C L et al. (1996) Seroepidemiology of Entamoeba histolytica in a slum in northeastern Brazil. Am J Trop Med Hyg 55:693-7
Walser, B L; Lima, A A; Guerrant, R L (1996) Effects of high-dose oral vitamin A on diarrheal episodes among children with persistent diarrhea in a northeast Brazilian community. Am J Trop Med Hyg 54:582-5
Zu, S X; Li, J F; Barrett, L J et al. (1994) Seroepidemiologic study of Cryptosporidium infection in children from rural communities of Anhui, China and Fortaleza, Brazil. Am J Trop Med Hyg 51:1-10

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