Pathological interaction between CD4 + T cells and B cells is one of the important mechanisms of systemic autoimmune diseases. Follicular helper T cells (Tfh) and peripheral helper T cells (Tph) are key cells for assisting B cells. Tph cell is a newly discovered helper T cell subset, and their phenotype is PD-1 highCXCR5 -CD4 +. Tph cell and Tfh cell have certain differences in phenotype, function, and site of action. It interacts with B cells, promoting the differentiation of B cells into plasma cells and the production of autoantibodies, as well as promoting the formation of ELS to maintain local inflammation and antibody responses. Tph cells have recently been reported in various autoimmune diseases such as rheumatoid arthritis, systemic lupus erythematosus, Sjogren′s syndrome, and IgG4-related diseases. This review summarizes the progress in peripheral immune response of Tph cells in different systemic autoimmune diseases, aiming to explore the new mechanism of autoantibody production and help to develop new diagnostic and therapeutic targets in the future.

Pathological interaction between CD4 + T cells and B cells is one of the important mechanisms of systemic autoimmune diseases. Follicular helper T cells (Tfh) and peripheral helper T cells (Tph) are key cells for assisting B cells. Tph cell is a newly discovered helper T cell subset, and their phenotype is PD-1 highCXCR5 -CD4 +. Tph cell and Tfh cell have certain differences in phenotype, function, and site of action. It interacts with B cells, promoting the differentiation of B cells into plasma cells and the production of autoantibodies, as well as promoting the formation of ELS to maintain local inflammation and antibody responses. Tph cells have recently been reported in various autoimmune diseases such as rheumatoid arthritis, systemic lupus erythematosus, Sjogren′s syndrome, and IgG4-related diseases. This review summarizes the progress in peripheral immune response of Tph cells in different systemic autoimmune diseases, aiming to explore the new mechanism of autoantibody production and help to develop new diagnostic and therapeutic targets in the future.