Fig. 4.

Peripheral blood mononuclear cell (PBMC) proliferative responses to ANCA antigens by ANCA⁺ vasculitis patients and controls (IgA nephropathy (IgAN) patients and normal controls). Proliferative responses are expressed as stimulation indices (SI), an SI = 1 is equivalent to no response, the bars represent the mean response. (a) PBMC proliferative responses to 10 μg/ml of heat-inactivated (HI) proteinase 3 (PR3). (b) PBMC proliferative responses to 10 μg/ml native PR3. (c) PBMC proliferative responses to 10 μg/ml HI myeloperoxidase (MPO). (d) PBMC proliferative responses to 25 μg/ml HI whole α-granules.