Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1994-6-23
pubmed:abstractText
The present study examined the quantitative and qualitative changes registered in the parasite-specific antibody response, cellular reactivity and cytokine production profile in onchocerciasis patients repeatedly treated with ivermectin over a period of 8 years. The densities of Onchocerca volvulus microfilariae (mf) in treated patients remained significantly reduced, whereas the number of permanently amicrofilaridermic patients (subclinical infection) increased with repeated treatments. In vitro cellular responses to O. volvulus antigen (OvAg) were highest (P < 0.01) in untreated control individuals exposed to infection, but negative for mf of O. volvulus (endemic normals). Cellular reactivity in repeatedly treated patients was higher at 84 than at 36 months post initial treatment (p.i.t); furthermore, the proliferative responses to OvAg, mycobacterial purified protein derivative (PPD) and streptococcal SL-O were greater (P < 0.05) at 84 months p.i.t. in amicrofilaridermic than in microfilaria-positive onchocerciasis patients. In amicrofilaridermic patients such reactivity approached the magnitude observed in endemic normals. Peripheral blood mononuclear cells (PBMC) from patients and endemic normals produced equivalent amounts of IL-2, IL-4 and interferon-gamma (IFN-gamma) in response to mitogenic stimulation with phytohaemagglutinin (PHA); in response to OvAg, however, significantly more IL-2 and IFN-gamma were produced by PBMC from subclinical amicrofilaridermic patients or endemic normals than by mf-positive patients. OvAg-specific production of IL-4 by PBMC from treated patients was lower at 84 than at 36 months p.i.t. At three months p.i.t. the titres of circulating OvAg-specific IgG1-3 had increased (P < 0.05), but they then continuously declined with repeated treatments. Only IgG1 and IgG4 bound to OvAg of mol. wt 2-12 kD at 1 month p.i.t., while recognition of OvAg of mol. wt 10-200 kD by IgG1, IgG2 and IgG4 reached a maximum intensity at 3-6 months p.i.t., with the overall intensity of binding to OvAg gradually weakening thereafter. These results suggest that onchocerciasis-associated immunosuppression is reversible following ivermectin-induced permanent clearance of microfilariae from the skin; and that a vigorous parasite-specific cellular reactivity and a sustained production of IL-2 and IFN-gamma in amicrofilaridermic individuals may contribute to controlling O. volvulus infection.
pubmed:commentsCorrections
http://linkedlifedata.com/resource/pubmed/commentcorrection/8187332-1354652, http://linkedlifedata.com/resource/pubmed/commentcorrection/8187332-1363185, http://linkedlifedata.com/resource/pubmed/commentcorrection/8187332-1516257, http://linkedlifedata.com/resource/pubmed/commentcorrection/8187332-15463411, http://linkedlifedata.com/resource/pubmed/commentcorrection/8187332-15463650, http://linkedlifedata.com/resource/pubmed/commentcorrection/8187332-1572089, http://linkedlifedata.com/resource/pubmed/commentcorrection/8187332-1583340, http://linkedlifedata.com/resource/pubmed/commentcorrection/8187332-1607688, http://linkedlifedata.com/resource/pubmed/commentcorrection/8187332-1822959, http://linkedlifedata.com/resource/pubmed/commentcorrection/8187332-1829892, http://linkedlifedata.com/resource/pubmed/commentcorrection/8187332-1834764, http://linkedlifedata.com/resource/pubmed/commentcorrection/8187332-1949145, http://linkedlifedata.com/resource/pubmed/commentcorrection/8187332-2019761, http://linkedlifedata.com/resource/pubmed/commentcorrection/8187332-203061, http://linkedlifedata.com/resource/pubmed/commentcorrection/8187332-2051025, http://linkedlifedata.com/resource/pubmed/commentcorrection/8187332-2198750, http://linkedlifedata.com/resource/pubmed/commentcorrection/8187332-2382096, http://linkedlifedata.com/resource/pubmed/commentcorrection/8187332-2393979, http://linkedlifedata.com/resource/pubmed/commentcorrection/8187332-2419430, http://linkedlifedata.com/resource/pubmed/commentcorrection/8187332-2449095, http://linkedlifedata.com/resource/pubmed/commentcorrection/8187332-2642916, http://linkedlifedata.com/resource/pubmed/commentcorrection/8187332-3125261, http://linkedlifedata.com/resource/pubmed/commentcorrection/8187332-3257994, http://linkedlifedata.com/resource/pubmed/commentcorrection/8187332-3263573, http://linkedlifedata.com/resource/pubmed/commentcorrection/8187332-3898885, http://linkedlifedata.com/resource/pubmed/commentcorrection/8187332-6123884, http://linkedlifedata.com/resource/pubmed/commentcorrection/8187332-6382708, http://linkedlifedata.com/resource/pubmed/commentcorrection/8187332-6530509, http://linkedlifedata.com/resource/pubmed/commentcorrection/8187332-6861374, http://linkedlifedata.com/resource/pubmed/commentcorrection/8187332-8356001
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
0009-9104
pubmed:author
pubmed:issnType
Print
pubmed:volume
96
pubmed:owner
NLM
pubmed:authorsComplete
N
pubmed:pagination
238-44
pubmed:dateRevised
2009-11-18
pubmed:meshHeading
pubmed:year
1994
pubmed:articleTitle
Ivermectin-facilitated immunity in onchocerciasis; activation of parasite-specific Th1-type responses with subclinical Onchocerca volvulus infection.
pubmed:affiliation
Institute of Tropical Medicine, University of Tübingen, Germany.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't