Immunization Strategies for the Control of Histoplasmosis

Abstract

Histoplasmosis is an infection caused by the dimorphic fungus Histoplasma capsulatum. Histoplasmosis is typically self-limited and presents asymptomatically in most people. Nevertheless, histoplasmosis can cause severe pulmonary disease and death. Histoplasmosis is increasingly found worldwide; however, it is best documented in the endemic region of the Mississippi river valley system in the Eastern part of the United States (US). Epidemiological studies from the US detailing the morbidity, mortality, and cost associated with histoplasmosis underscore the need to develop a vaccine.

Purpose of review: This review will detail some of the major developments in potential vaccines against histoplasmosis, with particular emphasis on those that could be used to immunize immunocompromised hosts. Additionally, this review will highlight some non-traditional vaccine-like ideas for the prevention of diverse mycoses.

Recent findings: Historically, immunization strategies against histoplasmosis have largely focused on identifying immunogenic proteins that confer protection in animal models. More recently, novel active, therapeutic, and immunomodulatory strategies have been explored as potential alternatives for those with various immune-deficiencies.

Summary: The studies summarized in this review demonstrate that more research is needed to clarify the immunobiology, clinical role and efficacy of each candidate vaccine in the ever-expanding potential armamentarium against histoplasmosis.

Keywords: H. capsulatum; T cells; antibodies; histoplasmosis; immune-therapy; vaccine.