Qom University of Medical Sciences Journal

Background and Objectives:Haemophilusinfluenzae is a bacterium that can act as a pathogen of human respiratory tract. Its infections have been traditionally treated with antibiotics, and then the use of conjugate vaccines has been very successful in prevention of infectious diseases. These vaccines consisted of capsular polysaccharide of H. influenzaewith an immunogenic protein. The aim of this study was molecular analysis of oapAgene in IranianH. influenzae strains as a conserve immunogenic protein for vaccine candidate.

Methods:ClinicalH. influenzae strains were collected from Milad Hospital in Tehran, and cultured on chocolate agar. After diagnostic test, biochemical tests were performed for distinguishing strains biotype. The DNA extracted by boiling method and specific PCR reactions were designed for oapAgene molecular analysis. Finally sequencing of PCR products was performed for confirming our results.

Results: The results of PCR exhibited that 79% of clinical samples had 95-99% similarity to NCBI sequences of H. influenzaeoapA gene, and the remaining 21% had a 125 nucleotide deletion and 94-96% similarity to NCBI sequences. Also this study showed that all strains having 125 nucleotide deletion (NontypeableH. influenzaeand H. influenzae type b) had 95-99% similarity to NCBI sequences. The results of determining the biotype revealed that the studied strains were related to different biotypes.

Conclusion: The results of this study suggested that use of oapA gene protein for production of vaccine against H. influenzae type b be further considered.