Can Recombinant Cryptococcus neoformans HSP۷۰ be a Candidate for Developing an ELISA Kit?

Backgrounds: Cryptococcus neoformans is an encapsulated fungal pathogen that causes lifethreateningmeningoencephalitis in immunocompromised patients. This yeast secretes severalpotent immunogenic proteins by secretory vesicular mechanisms, such as HSP۷۰ chaperone.This study aimed to evaluate the immunogenicity of recombinant C. neoformans HSP۷۰ for thedevelopment of a simple and sensitive method for the diagnosis of Cryptococcus infections.Materials and Methods: The PCR-amplified HSP۷۰ gene was cloned into a PET-۲۸a (+)expression vector. The purified recombinant HSP۷۰ (rHSP۷۰) was evaluated by western blottingusing an anti-His Tag-HRP antibody and then used for immunization of a rabbit. The serum ofthe immunized rabbit was tested against the whole lysate of C. neoformans in ELISA.Results: The antibodies in the rabbit’s serum recognized lysate of C. neoformans yeast. Thehighest antibody levels were achieved after the third booster injection.Conclusion: Recognition of the HSP۷۰ available in the whole cell lysate of C. neoformans byantibodies in serum of the rabbit immunized with rHsp۷۰ showed that the purified recombinantprotein presents the antigenic epitopes. Moreover, the results showed that rHSP۷۰ efficientlyinduced a specific antibody response in the immunized rabbit with a high titer, indicating thedesirable antigenicity and immunogenicity of the recombinant protein. The rHSP۷۰ showed to bea reliable candidate for the designing and development of an ELISA kit for early detection ofcryptococcosis, and to screen a large number of specimens.

کلیدواژه ها:

Cryptococcus neoformans ، ELISA ، Recombinant ، immunogenicity ، HSP۷۰