BACKGROUND: It has previously been shown that RP105, a new B cell surface protein, is lost in activated human B cells. OBJECTIVE: To investigate whether there is a difference in B cell activation between patients with dermatomyositis (DM) and those with polymyositis (PM) using RP105 as a marker. METHODS: The population of RP105 negative B cells (activated B cells) in the peripheral blood mononuclear cells of seven patients with dermatomyositis (DM) and 11 with polymyositis (PM) was analysed by flow cytometry. RESULTS: The percentage of RP105 negative B cells in the peripheral blood of patients with PM was low (5.8 (SD 2.4)%), similar to that of normal subjects. In contrast, all patients with DM showed increased RP105 negative B cell populations (33.0 (6.9)%). Bronchoalveolar lavage fluid from a patient with DM and active interstitial pneumonitis contained a large number of RP105 negative B cells. CONCLUSION: These findings suggest that the expansion of RP105 negative B cells is a hallmark of DM, and that B cell activation in DM may be pathogenetically different from that in PM.
BACKGROUND: It has previously been shown that RP105, a new B cell surface protein, is lost in activated human B cells. OBJECTIVE: To investigate whether there is a difference in B cell activation between patients with dermatomyositis (DM) and those with polymyositis (PM) using RP105 as a marker. METHODS: The population of RP105 negative B cells (activated B cells) in the peripheral blood mononuclear cells of seven patients with dermatomyositis (DM) and 11 with polymyositis (PM) was analysed by flow cytometry. RESULTS: The percentage of RP105 negative B cells in the peripheral blood of patients with PM was low (5.8 (SD 2.4)%), similar to that of normal subjects. In contrast, all patients with DM showed increased RP105 negative B cell populations (33.0 (6.9)%). Bronchoalveolar lavage fluid from a patient with DM and active interstitial pneumonitis contained a large number of RP105 negative B cells. CONCLUSION: These findings suggest that the expansion of RP105 negative B cells is a hallmark of DM, and that B cell activation in DM may be pathogenetically different from that in PM.
Authors: M Aleksza; A Szegedi; P Antal-Szalmás; B Irinyi; L Gergely; A Ponyi; J Hunyadi; S Sipka; M Zeher; G Szegedi; K Dankó Journal: Ann Rheum Dis Date: 2005-04-13 Impact factor: 19.103
Authors: Erin M Wilfong; Todd Bartkowiak; Katherine N Vowell; Camille S Westlake; Jonathan M Irish; Peggy L Kendall; Leslie J Crofford; Rachel H Bonami Journal: Front Immunol Date: 2022-02-21 Impact factor: 8.786
Authors: K Mizuno; A Yachie; S Nagaoki; H Wada; K Okada; M Kawachi; T Toma; A Konno; K Ohta; Y Kasahara; S Koizumi Journal: Clin Exp Immunol Date: 2004-07 Impact factor: 4.330