Effect of active immunization with IL-17A on B cell function and infection risk in pristane-induced lupus model

The aim of this study was to determine the effect of active immunization of interleukin (IL)-17A to inhibit B cell functions and monitor the risk of infection in a pristane-induced lupus mice model.

Female Balb/c mice were given a single intraperitoneal injection of 0.5 mL pristane. IL-17A was coupled to keyhole limpet hemocyanin (KLH) and given to mice in three different doses: D0 (0 μg/mL), D1 (1 μg/mL), and D2 (10 μg/mL). The vaccine was given three times with 3-week intervals. At day 42, mice were injected intraperitoneally with methicillin-resistant Staphylococcus aureus (MRSA) and monitored for 3 weeks. Plasma cells proliferation, Th17 and plasma cell percentages were measured by flow cytometry; anti-IL-17A antibody titers, IL-17A, and anti-double-stranded DNA (anti-dsDNA) levels were measured by enzyme-linked immunosorbent assay; and MRSA colonization was measured by bacterial counter.

Anti-IL-17A antibody titers were significantly higher in D2 compared to D0 (P = 0.012). Serum IL-17A levels were also significantly lower in D2 compared to D0 (P = 0.000) while Th17 percentages were not significantly different between groups. D2 was also had significantly lower anti-dsDNA (P = 0.021), lower plasma cell percentages (P = 0.000) and lower B cell proliferation rate (P = 0.001) compared to D0. Analysis for the risk of infection also revealed that D2 did not increase the risk of infection compared to D0 (P = 0.504).

Active immunization with IL-17A coupled to KLH was able to induce a high titer of neutralizing antibodies against IL-17A and inhibit B cell functions without increasing the risk of infection in a pristane-induced lupus mice model.