Increased susceptibility to Strongyloides venezuelensis in mice due to Mycobacterium bovis co-infection which modulates production of Th2 cytokines.
An estimated quarter of the world's population possesses an infection caused by gastrointestinal nematodes, which induce a Th2 type immune response. Concomitant infection of nematodes with Mycobacterium tuberculosis, which induces a predominantly Th1 type response, is very frequent in tropical and subtropical regions. This study examined immune responses of BALB/c mice infected with Strongyloides venezuelensis and then co-infected with Mycobacterium bovis. The number of worms in the intestine, eggs in feces, cytokine production in lungs and intestine and the expression of CD80, CD86, CTLA-4 and CD28 cell markers on pulmonary cells were analysed. Our results indicate that co-infected mice had an increased parasite burden, which correlates with elevated IFN-gamma and IL-10 cytokine production and decreased IL-4 and IL-13. Moreover, decreased expression of CD80 and increased expression of CTLA-4 were observed in co-infected mice. Our data point out that susceptibility to Strongyloides venezuelensis infection is increased by Mycobacterium bovis co-infection, resulting in higher parasite survival.
Carmo
A M
AM
Departamento de Parasitologia, Microbiologia e Imunologia, Instituto de Ciências Biológicas, Universidade Federal de Juiz de Fora, Juiz de Fora, 36036-330, Minas Gerais, Brazil.
Vicentini
M A
MA
Dias
A T
AT
Alves
L L
LL
Alves
C C S
CC
Brandi
J S
JS
De Paula
M L
ML
Fernandes
A
A
Barsante
M M
MM
Souza
M A
MA
Teixeira
H C
HC
Negrão-Corrêa
D
D
Ferreira
A P
AP
D000818:Animals; D016207:Cytokines / Q000378:metabolism*; D004198:Disease Susceptibility; D005243:Feces / Q000469:parasitology; D007371:Interferon-gamma / Q000378:metabolism; D016753:Interleukin-10 / Q000378:metabolism; D007422:Intestines / Q000276:immunology / Q000469:parasitology; D008168:Lung / Q000276:immunology / Q000469:parasitology; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D009164:Mycobacterium Infections / Q000150:complications* / Q000276:immunology / Q000382:microbiology; D009163:Mycobacterium bovis / Q000276:immunology / Q000472:pathogenicity; D010270:Parasite Egg Count; D051381:Rats; D017208:Rats, Wistar; D013321:Strongyloides / Q000145:classification / Q000472:pathogenicity*; D013322:Strongyloidiasis / Q000150:complications* / Q000276:immunology / Q000469:parasitology; D018418:Th2 Cells / Q000276:immunology*
D016207:Cytokines; D016753:Interleukin-10; D007371:Interferon-gamma