Previous Article | Next Article ![]()
Infect. Immun., Jan 1998, 18-27, Vol 66, No. 1
PC Melby, YZ Yang, J Cheng and W Zhao
Infection with the protozoan Leishmania donovani can cause serious visceral
disease or subclinical infection in humans. To better understand the
pathogenesis of this dichotomy, we have investigated the host cellular
immune response to cutaneous or visceral infection in a murine model. Mice
infected in the skin developed no detectable visceral parasitism, whereas
intravenous inoculation resulted in hepatosplenomegaly and an increasing
visceral parasite burden. Spleen cells from mice with locally controlled
cutaneous infection showed strong parasite-specific proliferative and gamma
interferon (IFN-gamma) responses, but spleen cells from systemically
infected mice were unresponsive to parasite antigens. The in situ
expression of IFN-gamma, interleukin-4 (IL-4), IL-10, IL-12, and inducible
nitric oxide synthase (iNOS) mRNAs was determined in the spleen, draining
lymph node (LN), and cutaneous site of inoculation. There was considerably
greater expression of IFN-gamma and IL-12 p40 mRNAs in the LN draining a
locally controlled cutaneous infection than in the spleen following
systemic infection. Similarly, there was a high level of IFN-gamma
production by LN cells following subcutaneous infection but no IFN- gamma
production by spleen cells following systemic infection. Splenic IL-4
expression was transiently increased early after systemic infection, but
splenic IL-10 transcripts increased throughout the course of visceral
infection. IL-4 and IL-10 mRNAs were also increased in the LN following
cutaneous infection. iNOS mRNA was detected earlier in the LN draining a
cutaneous site of infection compared to the spleen following systemic
challenge. Thus, locally controlled cutaneous infection was associated with
antigen-specific spleen cell responsiveness and markedly increased levels
of IFN-gamma, IL-12, and iNOS mRNA in the draining LN. Progressive splenic
parasitism was associated with an early IL-4 response, markedly increased
IL-10 but minimal IL-12 expression, and delayed expression of iNOS.
Copyright © 1998, American Society for Microbiology
Regional differences in the cellular immune response to experimental cutaneous or visceral infection with Leishmania donovani
The Audie L. Murphy Veterans Administration Hospital, and Department of Medicine, The University of Texas Health Science Center, San Antonio 78284-7881, USA. melby@uthscsa.edu
This article has been cited by other articles:
| J. Bacteriol. | J. Virol. | Eukaryot. Cell |
|---|
| Microbiol. Mol. Biol. Rev. | Clin. Vaccine Immunol. | All ASM Journals |
|---|