Identifying Toll-Like Receptor Expression in Molluscum Contagiosum

Toll-like receptors (TLRs) are known to be involved in the immunogenic response in a variety of dermatological disorders including psoriasis, condyloma acuminata, atopic dermatitis, and cutaneous T-cell lymphoma. However, the expression of TLRs in Molluscum contagiosum has not yet been clearly defined.Expression of TLRs 1-9 was examined in molluscum by immunohistochemical staining. Results showed TLRs 2,5, and 6 stained most intensely in both the epidermis and infundibulum in molluscum cases. It was also found that there was minimal staining of TLRs 7 and 8 in molluscum cases. Condyloma acuminata cases were used as control. The nuclear factor-kappa B activation pathway was confirmed by staining for p65. All cases stained moderately for p65. The lack of expression of TLRs 7 and 8 in molluscum suggests therapeutic agonists to TLR 7 such as imiquimod may be ineffective in the treatment of molluscum. Further studies to delineate the mechanisms of viral induced immune responses will lead to the development of better anti-viral medications.