Molluscum Contagiosum Virus

Persistence Pays Off

Crystal M H Randall; Joanna L Shisler

Disclosures

Future Virology. 2013;8(6):561-573. 

In This Article

Abstract and Introduction

Abstract

The molluscum contagiosum (MC) virus (MCV) is a dermatotropic poxvirus, and the causative agent of MC. Unlike smallpox and human monkeypox diseases, MC is nonlethal, common and worldwide. Additionally, little inflammation is associated with MC papules, and MC can persist for months to years. Such a prolonged infection implies that MCV successfully manipulates the host environment. This review highlights recent findings that reveal how MCV infections manipulate localized host immune responses and which immune response are key for the eventual resolution of MC. Also highlighted here are the MCV proteins that inhibit apoptosis, inflammation and immune cell recruitment or that induce cellular proliferation, with discussion as to how these proteins dampen localized antiviral immune responses. Lastly, this review discusses how the immune evasion tactics of MCV have led to insights about specific functions of the human innate and adaptive immune responses.

Introduction

The molluscum contagiosum (MC) virus (MCV) is a dermatotropic poxvirus that causes umbilicated skin papules (MC) in humans. While MC is a benign disease, it is important to human health because of its common incidence, its persistence and the lack of a cure. As such, MC impacts patients and their families psychologically and economically.

Here, we review recent histological studies of MC and epidemiological studies of MCV infections, which show that inflammatory responses control MCV-induced disease. However, MCV encodes proteins that inhibit apoptosis, inflammation and immune cell recruitment or induce cellular proliferation, and these proteins are presumably a means to battle the immune response. Potential cures for MCV may lie in neutralizing these immune evasion proteins to tip the scales in favor of the host immune system to eliminate MCV infections. Moreover, systems must be developed to propagate MCV and to recapitulate the disease in an animal model for future studies. This review highlights recent advances made in the field of MCV pathogenesis, and the clinical and biological implications of these findings in understanding how MCV manipulates the host cell and its surrounding environment to cause persistent disease.

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