title: A study on relationship among apoptosis rates, number of peripheral T cell subtypes and disease activity in rheumatoid arthritis.
abstract: OBJECTIVE
  Rheumatoid arthritis is characterized by type 17 helper T cell (Th17)/regulatory T cell (Treg) imbalance. The objective of this article is to study whether insufficient apoptosis contributes to the imbalance of Th17/Treg in rheumatoid arthritis.
  
  
  METHODS
  Twenty-one rheumatoid arthritis patients and eight healthy volunteers were involved in this study. The percentage of CD4(+) interleukin (IL)-17(+) T cells and CD4(+) transcription factor-forkhead box protein 3 (Foxp3)(+) T cells were measured by flow cytometry, and active caspase-3 labeling was used to detect early apoptosis. The number of T cell subtypes in peripheral blood between the two groups was compared, as well as the apoptotic ratio.
  
  
  RESULTS
  Neither the number of Th17 nor Treg cells was significantly different between rheumatoid arthritis patients and healthy controls. However, the number of regulatory T cells positively correlated with erythrocyte sedimentation rate, Disease Activity Score of 28 joints and rheumatoid factor. For the apoptosis of T cell subtypes, the percentage of apoptotic Th17 cells was higher in peripheral blood of rheumatoid arthritis patients compared to controls. Furthermore, peripheral Th17 cells were more sensitive to apoptosis than Treg cells, but there was no difference between rheumatoid arthritis patients and controls.
  
  
  CONCLUSIONS
  It seemed that there was no relationship between the number and apoptosis ratio of peripheral Th17/Treg cells. But the number of Treg cells positively correlated with disease activity. Furthermore, Th17 cells are more sensitive to apoptosis after freezing, especially in RA patients. This serendipitous finding may provide new areas for the further study of these two cell populations.
authors.affiliation: Department of Rheumatology and Clinical Immunology, Beijing University First Hospital, Beijing, China.
authors.forename: Lanlan
authors.initials: L
authors.lastname: Ji
authors.affiliation: Department of Rheumatology and Clinical Immunology, Beijing University First Hospital, Beijing, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Geng
authors.affiliation: Department of Rheumatology and Clinical Immunology, Beijing University First Hospital, Beijing, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Zhou
authors.affiliation: Department of Rheumatology and Clinical Immunology, Beijing University First Hospital, Beijing, China.
authors.forename: Zhuoli
authors.initials: Z
authors.lastname: Zhang
mesh_terms: D000328:Adult; D000368:Aged; D017209:Apoptosis; D001172:Arthritis, Rheumatoid / Q000188:drug therapy / Q000276:immunology / Q000473:pathology*; D015415:Biomarkers / Q000097:blood; D018791:CD4 Lymphocyte Count; D016022:Case-Control Studies; D053148:Caspase 3 / Q000097:blood; D005260:Female; D005434:Flow Cytometry; D051858:Forkhead Transcription Factors / Q000097:blood; D006801:Humans; D008297:Male; D008875:Middle Aged; D012720:Severity of Illness Index; D016176:T-Lymphocyte Subsets / Q000276:immunology / Q000473:pathology*; D050378:T-Lymphocytes, Regulatory / Q000276:immunology / Q000473:pathology*; D058504:Th17 Cells / Q000276:immunology / Q000473:pathology*
chemical_list: D015415:Biomarkers; C418974:FOXP3 protein, human; D051858:Forkhead Transcription Factors; C505407:CASP3 protein, human; D053148:Caspase 3
keywords: Th17 cells; apoptosis; regulatory T cells; rheumatoid arthritis