Suppression of adaptive immunity to heterologous antigens during Plasmodium infection through hemozoin-induced failure of dendritic cell function

Millington, O. R., Di Lorenzo, C., Phillips, R. S., Garside, P. and Brewer, J. M. (2005) Suppression of adaptive immunity to heterologous antigens during Plasmodium infection through hemozoin-induced failure of dendritic cell function. Journal of Biology, 5, 5. (doi: 10.1186/jbiol34) (PMID:16611373) (PMCID:PMC1561486)

Abstract

Background: Dendritic cells (DCs) are central to the initiation and regulation of the adaptive immune response during infection. Modulation of DC function may therefore allow evasion of the immune system by pathogens. Significant depression of the host's systemic immune response to both concurrent infections and heterologous vaccines has been observed during malaria infection, but the mechanisms underlying this immune hyporesponsiveness are controversial. Results: Here, we demonstrate that the blood stages of malaria infection induce a failure of DC function in vitro and in vivo, causing suboptimal activation of T cells involved in heterologous immune responses. This effect on T-cell activation can be transferred to uninfected recipients by DCs isolated from infected mice. Significantly, T cells activated by these DCs subsequently lack effector function, as demonstrated by a failure to migrate to lymphoid-organ follicles, resulting in an absence of B-cell responses to heterologous antigens. Fractionation studies show that hemozoin, rather than infected erythrocyte (red blood cell) membranes, reproduces the effect of intact infected red blood cells on DCs. Furthermore, hemozoin-containing DCs could be identified in T-cell areas of the spleen in vivo. Conclusion: Plasmodium infection inhibits the induction of adaptive immunity to heterologous antigens by modulating DC function, providing a potential explanation for epidemiological studies linking endemic malaria with secondary infections and reduced vaccine efficacy.

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Di Lorenzo, Miss Caterina and Millington, Dr Owain and Brewer, Professor James and Garside, Professor Paul and Phillips, Professor Stephen
• Authors: Millington, O. R., Di Lorenzo, C., Phillips, R. S., Garside, P., and Brewer, J. M.
• Subjects: Q Science > QR Microbiology > QR180 Immunology
• College/School: College of Medical Veterinary and Life Sciences; College of Medical Veterinary and Life Sciences > School of Infection & Immunity; College of Medical Veterinary and Life Sciences > School of Biodiversity, One Health & Veterinary Medicine
• Journal Name: Journal of Biology
• Publisher: BioMed Central
• ISSN: 1475-4924
• ISSN (Online): 1475-4924
• Copyright Holders: Copyright © 2006 Millington et al.
• First Published: First published in Journal of Biology 5: 5
• Publisher Policy: Reproduced under a Creative Commons License