Foxp3 expression in lesions of the different clinical forms of American tegumentary leishmaniasis.
As the diversity in clinical presentation of American tegumentary leishmaniasis (ATL) is determined mainly by the immune response of host, our aim was to evaluate the in situ expression of Foxp3 [marker of regulatory T (Treg) cell] in lesions of the different clinical forms of ATL. Foxp3(+) cells were observed in 39.5% (32/81) of the samples and the number of positive cells was low in all the clinical forms. Even presenting a significantly lower number of CD4(+) T cells, diffuse cutaneous leishmaniasis (DCL) showed a higher expression of Foxp3 when compared with localized cutaneous leishmaniasis (LCL) and mucocutaneous leishmaniasis (MCL). In LCL and MCL, the number of Foxp3(+) cells correlated positively with the number of apoptotic cells (active caspase-3(+) cells). A positive correlation was also observed between the expression of active caspase-3 and FasL in these clinical forms. Our data suggest that increased number of Treg cells may be associated to the hyporesponsiveness observed in DCL and also indicate that the apoptosis may be a possible mechanism of action of Foxp3(+) Treg cell in LCL and MCL. However, further studies are required to better understand the mechanism of action of Treg cell.
Carneiro
F P
FP
Department of Pathology, University of Brasília, Brasília, Brazil. fabianapirani@hotmail.com
De Magalhães
A V
AV
De Jesus Abreu Almeida Couto
M
M
Bocca
A L
AL
Muniz-Junqueira
M I
MI
Ribeiro Sampaio
R N
RN
D000293:Adolescent; D000328:Adult; D000368:Aged; D000818:Animals; D017209:Apoptosis; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D053148:Caspase 3 / Q000096:biosynthesis; D002648:Child; D002675:Child, Preschool; D053222:Fas Ligand Protein / Q000096:biosynthesis; D005260:Female; D051858:Forkhead Transcription Factors / Q000096:biosynthesis*; D006801:Humans; D007108:Immune Tolerance; D007896:Leishmaniasis / Q000276:immunology* / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D050378:T-Lymphocytes, Regulatory / Q000276:immunology; D055815:Young Adult
C505661:FASLG protein, human; C418974:FOXP3 protein, human; D053222:Fas Ligand Protein; D051858:Forkhead Transcription Factors; D053148:Caspase 3