Nephrol Dial Transplant

Nephrol Dial Transplant. peptide pools. In addition, 10 WG patients TD-198946 and eight healthy controls that did not proliferate to whole PR3 did proliferate to pools of PR3 peptides. Although more WG patients tended to react to particular peptide pools, no significant difference was seen between lymphocyte proliferation to PR3 peptides of WG patients and that of healthy controls. The pools of peptides recognized were mainly located at the N- and C-terminus of PR3. No correlation was observed between HLA type and proliferation on particular peptide pools. No proliferation of PBMC was observed to single peptides. In conclusion, T cells of WG patients proliferate more frequently to PR3 peptides than to the whole PR3 protein. Peptides derived from the signal sequence, the propeptide or peptides located at the C-terminus of PR3 induce highest levels of proliferation. No specific PR3 sequence could be identified that was preferentially recognized by PBMC of WG patients compared with controls. proliferative capacity to PR3 of peripheral blood mononuclear cells (PBMC) from WG patients. However, TD-198946 only a small proportion of WG patients as well as some healthy controls showed proliferation to PR3 or crude granular extracts of neutrophils [20C26]. T cell proliferation to PR3 was found in a range of 24% [23] to 63% [24] of WG patients and in a range of 0% [21,23,26] to 42% [25] in healthy controls. CEBPE Nonetheless, most authors found a significant difference between WG patients and healthy controls, as WG patients proliferated more frequently to PR3 compared with healthy controls [22,24C26]. King investigated the relevant PR3 peptides responsible for the proliferation of PBMC from WG patients, but only one out of 18 patients responded to PR3 peptides [25]. So, the relevant peptides responsible for the proliferation to PR3 have not yet been identified. The objective of this study was to analyse the proliferative capacity of PBMC from WG patients to peptides of PR3 as well as to PR3. In order to identify further relevant peptides, overlapping synthetic peptides were used spanning the entire sequence of PR3 including the signal and prosequence. Each peptide was 15 amino acids in length with an overlap of 10 amino acids, and all stretches of 11 amino acids of the PR3 sequence were available, in contrast to the previous study where not all stretches of nine amino acids were available, so some relevant immunogenic peptides might have been missed [25]. In previous studies, lymphocyte proliferation of WG patients and healthy controls to PR3 was found at PR3 concentrations ranging from 01 g/ml [22] to 20 g/ml [24]. As shown in those studies, different proportions of WG patients and healthy controls proliferate when varying PR3 concentrations are used [22,25,26]. Therefore, we used PR3 peptides at three concentrations in order to find optimal stimulation. Here we provide evidence that a higher level of proliferation of autoreactive T cells of WG patients was induced by peptides of PR3 than by the whole PR3 protein. Peptides derived from the signal sequence, the propeptide or the C-terminus of PR3 induced highest levels of proliferation by PBMC of WG patients and healthy controls. Nevertheless, no PR3 sequence could be identified that was specifically recognized by PBMC of WG patients. PATIENTS AND METHODS Patients and controls Patients who were newly diagnosed between January 1987 and January 1997 with PR3-ANCA-associated WG were considered for inclusion in the study. TD-198946 Diagnosis of WG was established according to clinical and histological criteria [1]. Patients fulfilled the American College of Rheumatology criteria for WG [27] and all patients had biopsy-proven NCGN at the time of diagnosis. In order to exclude non-responsiveness due to immunosuppressive drugs or severe disease activity, only patients in remission without significant immunosuppressive treatment (cyclophosphamide 25 mg daily) at the time of testing were included. Previously, all patients has been treated with cyclophosphamide and prednisolone. At the time of diagnosis, sera had been tested for ANCA by indirect immunofluorescence (IIF) and by ELISA for antibodies to PR3, myeloperoxidase (MPO) and human leucocyte elastase (HLE). All patients were positive for PR3-ANCA only (see below). Thirteen WG patients were tested (seven males and six females). Their median age was 60 years (range 28C73 years). Clinical and laboratory data of the patients are outlined in Table 1. Sera drawn at the time of this study were tested for ANCA by IIF and PR3-ANCA by antigen-specific direct ELISA. The control group consisted of 12 healthy volunteers (eight males and four females) and their median age was 48 years (range 27C62 years). Table 1 Patient characteristics at the time of testing = 50)..