Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0851341 (infestation)
 10,121 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The effect of repeated infestations of Ixodes ricinus (L.) nymphs on BALB/c mice was studied. Four successive infectations resulted in an increase of tick feeding success. Tick yield and mean engorged weight increased and the length of the feeding period was reduced significantly (P < 0.05-0.01). The increase of specific anti-tick antibodies was not significant (P > 0.05). The blastogenic response of spleen lymphocytes to T-cell mitogens (Con A and PHA-P) was unimpaired or slightly enhanced, whereas the response to B-cell activators (LPS and PWM) was suppressed, as was the total antibody generation in vitro. The numbers of mast cells in murine skin at the tick attachment sites slightly decreased during the third infestation. The suppression of B-cell competence and of antibody generation, together with decrease of skin mast cell numbers in tick attachment sits, are considered to be responsible for enhancement of tick feeding success.
 ...
PMID:Immunosuppression and feeding success of Ixodes ricinus nymphs on BALB/c mice. 778 20

Helminth parasites drive dominant Th2 responses through an as yet unidentified pathway. We have previously shown that the rodent gastrointestinal nematode Nippostrongylus brasiliensis secretes products which selectively activate in vitro-derived dendritic cells to induce Th2 responses on in vivo transfer. We now show that, during active infection with this parasite, the draining mesenteric lymph node dendritic cell population is altered significantly. Although there is substantial expansion of DC numbers during infection, the CD86(hi)-CD8alpha(int)-CD11b(-) subset is markedly diminished, and expression levels of CD40, CD86 and CD103 are reduced. Notably, the reduced frequency of CD8alpha(int) DCs is evident only in those mesenteric lymph nodes draining the anterior site of infestation. In infections with the longer lived Heligmosomoides polygyrus, the proportion of CD8alpha(int) DCs in the MLNC falls to below 10% of total DC numbers by 35 days post-infection. Further, infection alters TLR responsiveness, as IL-12 production (as measured by ex vivo intracellular staining of CD11c(+) DCs) in response to LPS stimulation is reduced, while IL-6, TNF-alpha and in particular, IL-10 all increase following infection with either nematode parasite. These changes suggest the possibility that helminth parasites modulate gastrointestinal immunity both by inhibiting migration of CD8alpha(int) DCs to the draining lymph nodes, and modifying DC responsiveness in a manner which favours a Th2 outcome.
 ...
PMID:Dynamics of CD11c(+) dendritic cell subsets in lymph nodes draining the site of intestinal nematode infection. 1976 74