Analysis of regulatory T cell associated forkhead box P3 expression in the lungs of patients with sarcoidosis.
In pulmonary sarcoidosis, the typical T helper 1-mediated immune response in the lungs has been proposed to be co-ordinated by regulatory T cells; however, their exact role needs to be clarified. We used real-time polymerase chain reaction to study genes involved in regulatory T cell functions in CD4+ T cells isolated from bronchoalveolar lavage fluid (BALF) of patients (n = 24) and healthy subjects (n = 7). The genes included the transcription factor forkhead box P3 (FoxP3), interleukin (IL)-10, transforming growth factor-beta1 and chemokine receptor 2 (CCR2). The same genes were also studied in isolated BALF CD4+ T cell receptor AV2S3+ and AV2S3(-) T cells of patients with lung-restricted AV2S3 T cell expansions (n = 12). Intracellular staining of the FoxP3 protein was performed additionally in 14 patients and nine healthy subjects. mRNA expression of FoxP3, CCR2 and IL-10 was decreased significantly in BALF CD4+ T cells of patients. Flow cytometric analysis of CD4+ T cells also demonstrated a decreased frequency of FoxP3+ cells in the BALF and blood of sarcoidosis patients as well as a reduced intensity (mean fluorescence intensity) of FoxP3 expression in BALF FoxP3+ cells of patients. BALF CD4+AV2S3+ T cells expressed significantly lower levels of FoxP3 and CCR2 mRNA versus BALF CD4+AV2S3- T cells. The main conclusion of our study is that there is a reduced expression of regulatory T cell associated genes in BALF CD4+ T cells in sarcoidosis. In addition, our data suggest an effector function of AV2S3+ lung-accumulated T cells in sarcoidosis.
Idali
F
F
Karolinska Institutet, Department of Medicine, Unit of Respiratory Medicine, Stockholm, Sweden. farah.idali@ki.se
Wahlström
J
J
Müller-Suur
C
C
Eklund
A
A
Grunewald
J
J
D000328:Adult; D000368:Aged; D001992:Bronchoalveolar Lavage Fluid / Q000276:immunology; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D005260:Female; D051858:Forkhead Transcription Factors / Q000096:biosynthesis* / Q000235:genetics; D015870:Gene Expression / Q000276:immunology; D006801:Humans; D016753:Interleukin-10 / Q000096:biosynthesis / Q000235:genetics; D008168:Lung / Q000276:immunology / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D016133:Polymerase Chain Reaction / Q000379:methods; D012333:RNA, Messenger / Q000235:genetics; D054390:Receptors, CCR2 / Q000096:biosynthesis / Q000235:genetics; D017565:Sarcoidosis, Pulmonary / Q000276:immunology* / Q000503:physiopathology; D016176:T-Lymphocyte Subsets / Q000276:immunology; D050378:T-Lymphocytes, Regulatory / Q000378:metabolism*
C515334:CCR2 protein, human; C418974:FOXP3 protein, human; D051858:Forkhead Transcription Factors; D012333:RNA, Messenger; D054390:Receptors, CCR2; D016753:Interleukin-10