Format

Send to

Choose Destination
Immun Ageing. 2013 Jul 15;10(1):29. doi: 10.1186/1742-4933-10-29.

Cytokine and chemokine responses to helminth and protozoan parasites and to fungus and mite allergens in neonates, children, adults, and the elderly.

Author information

1
Institute for Tropical Medicine, Eberhard Karls Universität Tübingen, Wilhelmstrasse 27, Tübingen 72074, Germany.
2
Onchocerciasis Reference Laboratory, Institut National d'Hygiène, Sokodé, Togo.
3
Centre Hospitalier Universitaire Campus de Lomé, Université de Lomé, Lomé, Togo.
4
Centre Hospitalier Régional, Service Pédiatrie, Sokodé, Togo.
#
Contributed equally

Abstract

BACKGROUND:

In rural sub-Saharan Africa, endemic populations are often infected concurrently with several intestinal and intravascular helminth and protozoan parasites. A specific, balanced and, to an extent, protective immunity will develop over time in response to repeated parasite encounters, with immune responses initially being poorly adapted and non-protective. The cellular production of pro-inflammatory and regulatory cytokines and chemokines in response to helminth, protozoan antigens and ubiquitous allergens were studied in neonates, children, adults and the elderly.

RESULTS:

In children schistosomiasis prevailed (33%) while hookworm and Entamoeba histolytica/E. dispar was found in up to half of adults and the elderly. Mansonella perstans filariasis was only present in adults (24%) and the elderly (25%). Two or more parasite infections were diagnosed in 41% of children, while such polyparasitism was present in 34% and 38% of adults and the elderly. Cytokine and chemokine production was distinctively inducible by parasite antigens; pro-inflammatory Th2-type cytokine IL-19 was activated by Entamoeba and Ascaris antigens, being low in neonates and children while IL-19 production enhanced "stepwise" in adults and elderly. In contrast, highest production of MIP-1delta/CCL15 was present in neonates and children and inducible by Entamoeba-specific antigens only. Adults and the elderly had enhanced regulatory IL-27 cytokine responses, with Th2-type chemokines (MCP-4/CCL13, Eotaxin-2/CCL24) and cytokines (IL-33) being notably inducible by helminth- and Entamoeba-specific antigens and fungus-derived allergens. The lower cellular responsiveness in neonates and children highlighted the development of a parasite-specific cellular response profile in response to repeated episodes of exposure and re-infection.

CONCLUSIONS:

Following repeated exposure to parasites, and as a consequence of host inability to prevent or eliminate intestinal helminth or protozoa infections, a repertoire of immune responses will evolve with lessened pro-inflammatory and pronounced regulatory cytokines and chemokines; this is required for partial parasite control as well as for preventing inadequate and excessive host tissue and organ damage.

Supplemental Content

Full text links

Icon for BioMed Central Icon for PubMed Central
Loading ...
Support Center