Local reinfusion of B10 cells is effective in the treatment of pustular psoriasis

The identification, development and therapeutic potential of IL-10-producing regulatory B cells in multiple sclerosis

Regulatory B cells are a rare B-cell subset widely known to exert their immunosuppressive function via the production of interleukin-10 (IL-10) and other mechanisms. B10 cells are a special subset of regulatory B cells with immunoregulatory function that is fully attributed to IL-10. Their unique roles in the animal model of multiple sclerosis (MS) have been described, as well as their relevance in MS patients. This review specifically focuses on the identification and development of B10 cells, the signals that promote IL-10 production in B cells, the roles of B10 cells in MS, and the potential and major challenges of the application of B10-based therapies for MS.

Suppression of IL-23-mediated psoriasis-like inflammation by regulatory B cells

Psoriasis is an inflammatory cutaneous disease mediated by T-cell dependent immune responses; however, B cells are also considered to play an important role its development. Regulatory B cells (Bregs) regulate immune responses negatively through interleukin-10 (IL-10) production. This study aimed to investigate the role of Bregs in IL-23-mediated psoriasis-like inflammation in mice. Psoriasis-like inflammation was induced in B cell-specific phosphatase and tensin homolog (PTEN)-deficient mice, in which Bregs were significantly expanded, and in their controls, by intradermal injection of 20 μL phosphate-buffered saline (PBS) containing 0.5 μg rmIL-23 into one ear, every other day for 16 days. IL-23-mediated psoriasis-like inflammation was suppressed in B cell-specific PTEN-deficient mice along with decreased ear thickness and epidermal thickness on day 15. Moreover, adoptive transfer of B1 B cells suppressed IL-23-mediated psoriasis-like inflammation. rmIL-23-injected B cell-specific PTEN-deficient mice showed expanded regulatory T cells (Tregs) in the spleen and draining lymph nodes along with increased Bregs. Further, T helper (Th) 17 differentiation in the rmIL-23-injected ear was suppressed in B cell-specific PTEN-deficient mice. Overall, these results indicate that increased Bregs suppress IL-23-mediated psoriasis-like inflammation through Treg expansion and inhibition of Th17 differentiation. Thus, targeting Bregs may be a feasible treatment strategy for psoriasis.

Interleukin 23p19 inhibitors in chronic plaque psoriasis with focus on mirikizumab: A narrative review

Psoriasis, a T-cell mediated chronic dermatosis, has a complex etiopathogenesis. There has been extensive research into the aberrant immune response, which leads to the formation of clinical lesions, and the need for developing better and safer drugs has been unrelenting. The past two decades of research has opened up new areas of the immune pathway that can be targeted in order to control the disease. Therefore, we have seen the emergence of biologics which either target T-cell receptors or inhibit Tumor Necrosis Factor-alpha (TNF-α) or inhibit interleukins (IL) like IL-12, IL-17, IL-17 receptor, and more recently IL-23. Drugs specifically targeting the p19 subunit of IL-23 have shown promising results in the management of chronic plaque psoriasis. This has given way to the development of a new class of biologics, that is, the IL-23p19 inhibitors that have a better safety profile as compared to its predecessors. In this review, we shall scrutinize the role of IL-23 and Th17 cell signaling in the evolution of the psoriatic lesions and summarize the clinical experience with IL-23p19 inhibitors especially mirikizumab in the treatment of chronic plaque psoriasis.