An immunohistochemical study of abnormal keratinocyte differentiation in molluscum contagiosum

Abstract

To investigate abnormalities in the keratinization process in lesional epidermis of molluscum contagiosum, production of filaggrin, loricrin, Ted-H-1 antigen, involucrin, cystatin A and CD95 ligand (CD95L) was investigated using specific antibodies. Anti-filaggrin monoclonal antibody (MoAb) did not react with keratohyalin granules (KHG), but with the substance around virus particles in the stratum corneum. KHG reacted with anti-loricrin polyclonal antibody (PoAb) and anti-Ted-H-1 MoAb. Anti-involucrin PoAb and anti-cystatin A PoAb reacted with materials in the cytoplasm of the middle stratum spinosum to the stratum granulosum. CD95L was expressed in the cell membrane region of the living cell layers in lesional epidermis. These observations suggest that the keratinization process may be altered in molluscum contagiosum.

An immunohistochemical study of abnormal keratinocyte proliferation in molluscum contagiosum

“…From a kinetic point of view, the pathogenesis of molluscum contagiosum is poorly understood. Acanthosis, large keratohyalin granules and lack of reactivity of the keratohyalin granules to antifilaggrin monoclonal antibodies have suggested that the pathogenesis of molluscum contagiosum may involve abnormal differentiation of epidermal cells 2 . It is conceivable that activation/ inactivation of tumour suppressor genes or of cellular oncogenes plays a role in the pathogenesis of molluscum contagiosum lesions.…”

Mollusca contagiosa

“…The virus of MC has not been grown in tissue culture. [34] Histological examination after haematoxylin and eosin staining confirmed that the proliferative lesion was due to MC, and demonstration of the presence of molluscum bodies in a section can be revealed by in situ hybridization. Sequence analysis in the polymerase chain reaction is more sensitive than in situ hybridization and in dual infection with both MCV and Human papillomavirus (HPV) , the immunosuppressive genes of Molluscipox virus could enhance survival of the oncogenic types of HPV.…”

“…Abnormal keratinization process in lesional epidermis of MC can be proved by specific antibodies to filaggrin, loricrin, Ted-H-1 antigen, involucrin, cystatin A, and CD95 ligand. [26,34] Cell-mediated immunity seems to be important in host defence. The virus of MC has not been grown in tissue culture.…”

“…[29] Only humans are known to be affected except for one report each of molluscum contagiosum occurring in chimpanzees and a horse. [34] MCV might be transmitted directly from person to person or, which seems to be more frequent, by autoinoculation -i.e. by scratching or touching a lesion and transferring the virus from one site to another on the skin of the same individual.…”

Targeting the Retinoblastoma Protein by MC007L, Gene Product of the Molluscum Contagiosum Virus: Detection of a Novel Virus-Cell Interaction by a Member of the Poxviruses

“…In contrast to the acute generalized infection with high mortality caused by variola virus, MCV produces a chronic infection localized to epidermal tissue (10,27). This is characterized by hyperplasia and hypertrophy of the virusinfected keratinocytes (7,35,37), and MCV-infected tissue shows an abnormal expression of proteins of the cytoskeleton and cell cycle (35,37). In the absence of a functional immune system, MCV causes giant molluscum, with extensive disfiguring lesions (19).…”