tailieunhanh - Báo cáo y học: " Phenotypic characteristics of human type II alveolar epithelial cells suitable for antigen presentation to T lymphocytes"

Tuyển tập các báo cáo nghiên cứu về y học được đăng trên tạp chí y học 'Respiratory Research cung cấp cho các bạn kiến thức về ngành y đề tài: Phenotypic characteristics of human type II alveolar epithelial cells suitable for antigen presentation to T lymphocytes. | Corbière et al. Respiratory Research 2011 12 15 http content 12 1 15 RESPIRATORY RESEARCH RESEARCH Open Access Phenotypic characteristics of human type II alveolar epithelial cells suitable for antigen presentation to T lymphocytes I r I 1 1 2 3 2 14 Véronique Corbière1 Violette Dirix Sarah Norrenberg2 Mattéo Cappello3 Myriam Remmelink2 Frangoise Mascart1 4 Abstract Background Type II alveolar epithelial cells AECII are well known for their role in the innate immune system. More recently it was proposed that they could play a role in the antigen presentation to T lymphocytes but contradictory results have been published both concerning their surface expressed molecules and the T lymphocyte responses in mixed lymphocyte cultures. The use of either AECII cell line or fresh cells could explain the observed discrepancies. Thus this study aimed at defining the most relevant model of accessory antigen presenting cells by carefully comparing the two models for their expression of surface molecules necessary for efficient antigen presentation. Methods We have compared by flow cytometry the surface expression of the major markers involved in the immunological synapse on the A549 cell line the most popular model of type II alveolar epithelial cells and freshly isolated cells. HLA-DR CD80 CD86 ICOS-L CD54 CD58 surface expression were studied in resting conditions as well as after IFN-y TNF-a treatment two inflammatory cytokines known to modulate some of these markers. Results The major difference found between the two cells types was the very low surface expression of HLA-DR on the A549 cell line compared to its constitutive expression on freshly isolated AECII. The surface expression of co-stimulatory molecules from the B7 family was very low for the CD86 B7-2 and ICOS-L B7-H2 and absent for CD80 B7-1 on both freshly isolated cells and A549 cell line. Neither IFN-g nor TNF-a could increase the expression of these classical co-stimulatory molecules. .