Identification and co-localization of perforin-like (TgPLP1) protein in Toxoplasma gondii bradyzoites

Research advances in interactions related to Toxoplasma gondii microneme proteins

Toxoplasma gondii microneme proteins (TgMICs), secreted by micronemes upon contact with host cells, are reported to play important roles in multiple stages of the T. gondii life cycle, including parasite motility, invasion, intracellular survival, and egress from host cells. Meanwhile, during these processes, TgMICs participate in many protein-protein and protein-carbohydrate interactions, such as undergoing proteolytic maturation, binding to aldolase, engaging the host cell receptors and forming the moving junction (MJ), relying on different types of ectodomains, transmembrane (TM) domains and cytoplasmic domains (CDs). In this review, we summarize the research advances in protein-protein and protein-carbohydrate interactions related to TgMICs, and their intimate associations with corresponding biological processes during T. gondii infection, which will contribute to an improved understanding of the molecular pathogenesis of T. gondii infection, and provide a basis for developing effective control strategies against T. gondii.

Perforin expression in eyelid sebaceous carcinomas: a useful and specific immunomarker for the differential diagnosis of eyelid carcinomas

PURPOSE

Eyelid sebaceous carcinoma (SC) remains a common diagnostic pitfall for both the clinician and histopathologist. The aim of this study was to describe perforin as a new marker in the immunohistochemistry panel for SC.

METHODS

A total of 29 cases were retrieved from the Pathology archives, including 11 sebaceous neoplasms (nine SC; two sebaceomas), 10 squamous cell carcinomas (SCC) and eight basal cell carcinomas (BCC). These were stained using the monoclonal antibody for perforin, epithelial membrane antigen (EMA), Ber-EP4 and adipophilin (ADP). Sensitivity and specificity of perforin as an immunohistologic marker for sebaceous tumours were compared to EMA, ADP and Ber-EP4.

RESULTS

Perforin stained strongly 9/11 (81%) of the sebaceous neoplasms (SN), 7/9 SC and 2/2 of sebaceomas (2/2), similar to ADP. Epithelial membrane antigen (EMA) stained 8/9 SC and was negative (1/2) or only very weakly expressed (1/2) in sebaceomas. The specificity of perforin in identifying SN versus SCC and BCC was 100% (95% CI 69-100), while EMA specificity in identifying SN varied according the comparison group (SCC: 50%, 95% CI 18-81, 100% (95% CI 63-100). Perforin better highlighted the intraepithelial spread of SC than EMA. Ber-EP4 was strongly expressed in six of nine SC, but was consistently negative in sebaceomas.

CONCLUSIONS

The expression pattern of perforin in sebaceous neoplasms enables us to recommend the use of perforin as a new immunohistochemical marker for sebaceous neoplasms.