A Review of Possible Triggering or Therapeutic Effects of Antimicrobial Vaccines on Psoriasis

Psoriasis is a chronic, immune-mediated disease resulting from interactions of genetic background with environmental triggering factors, such as trauma, infections and drugs. Dendritic cells, activated T-cells toward a Th1 and Th17 response and inflammatory cytokines [tumor necrosis factor (TNF)-alpha, IL-6, -12, -17, -22 and -23] are the key factors in psoriasis pathogenesis. Patients diagnosed with psoriasis are at increased risk of infection due to the nature of disease and immunosuppressive therapies. Vaccination is recommended to prevent infections in patients with psoriasis. Additionally, vaccines such as Mycobacterium vaccae, live attenuated varicella zoster virus and Leishmania amastigotes have been reported to induce improvement in psoriasis patients. It has been suggested that vaccines, targeting molecules in the immunopathogenesis of psoriasis, may be a new treatment option for psoriasis patients without any serious side effects. However, induction or worsening of the psoriasis and psoriatic arthritis followed by some vaccines (e.g., influenza, rubella, tetanus, BCG) has also been reported in the literature. In this review, we focus on the vaccines in psoriasis in terms of their both triggering and therapeutic effects