Patterns of cytokine production and proliferation by T lymphocytes differ in mice vaccinated or infected with Schistosoma mansoni.
C57BL/6 mice vaccinated with irradiated cercariae of Schistosoma mansoni are highly resistant to challenge infection. To examine the role of T-helper (Th) activity in these vaccinated (V20) mice, cells from skin- and lung-draining lymph nodes (LN) and the spleen were cultured in vitro with soluble schistosomular antigen. Peak proliferation and release of T-cell growth factor (TCGF) by axillary LN cells on Day 5, and by mediastinal LN cells on Day 18, reflected the kinetics of parasite migration. High levels of interferon-gamma (IFN-gamma) were detected and production was prolonged, particularly in the mediastinal LN. The majority of the above activity was ablated with anti-CD4 antibody. IFN-gamma production by spleen cells increased, whilst proliferation and TCGF release remained low. Although levels of proliferation were similar, more IFN-gamma was released by LN cells from V20 mice than by those from mice infected with normal parasites (NI). This difference in IFN-gamma production was magnified by the greater number of cells in LN of V20 than NI mice. On Day 22 post-exposure, 24-fold more IFN-gamma was produced per pair of axillary LN in the former group. LN cells from V20 mice produced interleukin (IL)-2 and IL-4, whereas those from NI mice released IL-2 but negligible IL-4. Greater quantities of IL-3 were secreted by cells from V20 than from NI mice. These results support the conclusion that IFN-gamma-producing memory Th cells, generated in the LN of V20 mice, play an important role in protective immunity against S. mansoni.
Pemberton
R M
RM
Dept. of Biology, University of York, U.K.
Smythies
L E
LE
Mountford
A P
AP
Wilson
R A
RA
D000818:Animals; D000947:Antigens, Helminth / Q000276:immunology; D002455:Cell Division / Q000276:immunology; D016207:Cytokines / Q000096:biosynthesis*; D005260:Female; D007371:Interferon-gamma / Q000096:biosynthesis; D007376:Interleukin-2 / Q000096:biosynthesis; D007377:Interleukin-3 / Q000096:biosynthesis; D015847:Interleukin-4 / Q000096:biosynthesis; D008198:Lymph Nodes / Q000276:immunology; D051379:Mice; D008810:Mice, Inbred C57BL; D012550:Schistosoma mansoni / Q000276:immunology; D012555:Schistosomiasis mansoni / Q000276:immunology*; D013154:Spleen / Q000276:immunology; D013601:T-Lymphocytes / Q000276:immunology* / Q000378:metabolism; D014611:Vaccination
D000947:Antigens, Helminth; D016207:Cytokines; D007376:Interleukin-2; D007377:Interleukin-3; D015847:Interleukin-4; D007371:Interferon-gamma