Data/hora: 06/06/2024 02:11:18

Provedor de dados: 	56	
País: 	Brazil	
Título: 	Low expression of antigen-presenting and costimulatory molecules by lung cells from tuberculosis patients	
Autores: 	Flores-Batista,V.C.S.; Boechat,N.; Lago,P.M.; Lazzarini,L.C.; Pessanha,L.R.; Almeida,A.S.; Mafort,T.T.; Kritski,A.L.; Ho,J.L.; Lapa-e-Silva,J.R.	
Data: 	2007-12-01	
Ano: 	2007	
Palavras-chave: 	Tuberculosis; Costimulatory molecules; CD86; MHC class II; HLA-DR.	
Resumo: 	Costimulatory and antigen-presenting molecules are essential to the initiation of T cell immunity to mycobacteria. The present study analyzed by immunocytochemistry, using monoclonal antibodies and alkaline phosphatase-anti-alkaline phosphatase method, the frequency of costimulatory (CD86, CD40, CD40L, CD28, and CD152) and antigen-presenting (MHC class II and CD1) molecules expression on human lung cells recovered by sputum induction from tuberculosis (TB) patients (N = 22) and non-TB controls (N = 17). TB cases showed a statistically significant lower percentage of HLA-DR+ cells than control subjects (21.9 ± 4.2 vs 50.0 ± 7.2%, P &lt; 0.001), even though similar proportions of TB cases (18/22) and control subjects (16/17, P = 0.36) had HLA-DR-positive-stained cells. In addition, fewer TB cases (10/22) compared to control subjects (16/17) possessed CD86-expressing cells (P = 0.04; OR: 0.05; 95%CI = 0.00-0.51), and TB cases expressed a lower percentage of CD86+ cells (P = 0.04). Moreover, TB patients with clinically limited disease (£1 lobe) on chest X-ray exhibited a lower percentage of CD86-bearing cells compared to patients with more extensive lung disease (&gt;1 lobe) (P = 0.02). The lower expression by lung cells from TB patients of HLA-DR and CD86, molecules involved in antigen presentation and activation of T cells, may minimize T cell recognition of Mycobacterium tuberculosis, fostering an immune dysfunctional state and active TB.	
Tipo: 	Info:eu-repo/semantics/article	
Idioma: 	Inglês	
Identificador: 	http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2007001200011	
Editor: 	Associação Brasileira de Divulgação Científica	
Relação: 	10.1590/S0100-879X2006005000141	
Formato: 	text/html	
Fonte: 	Brazilian Journal of Medical and Biological Research  v.40 n.12 2007	
Fonte: 	info:eu-repo/semantics/openAccess