A concise overview of immunological aspects and immune polarization against Soil-Transmitted Helminths (STHs)

Abstract

Introduction: Soil-transmitted helminths (STH) represent a common group of parasitic infections that commonly contract humans as their definitive hosts. This parasite has been declared the third most prevalent neglected tropical diseases (NTDs) globally. The intricate interplay between these parasites and the host immune response necessitates a comprehensive exploration of the immunological dynamics governing the response to STH for prospective insights. 

Main Text: This review aims to elucidate the immunological facets of STH during host infection, delving into the intricate pathologic interactions underscored by the multifaceted involvement of adaptive and acquired immune responses. This immune interaction produces two major outcomes, chronic infection and worm expulsion depending on immune predominant response (type 1 versus type 2 immunity). Type 1 immunity is notable for its function against intracellular pathogens yet unsuitable for parasitic infection. Meanwhile, type 2 immunity is typical for macro parasite. However, attention recently has been dragged towards the study of the immunomodulatory properties inherent to STH, as recent reports leverage this characteristic to discern immune responses and functions against various parasitic diseases. Immunomodulation properties of STH are primarily mediated by the presence of Excretory/secretory proteins (ESPs) and soluble products (SPs) which act as a double-edged sword, enhancing parasitic invasion yet blunting immune response. 

Conclusions: Understanding the immunological aspects of STH is imperative for fostering comprehension and effective management in the contemporary era, as the goal of eradicating STH as a neglected tropical disease remains distant. In addition, its immunomodulation properties bring several implications, particularly to the advancement of treating other diseases, such as autoimmune diseases.