Immune reactivity of sera obtained from brucellosis patients and vaccinated-rabbits to a fusion protein from Brucella melitensis.

OBJECTIVES: Brucella spp. are facultative intracellular pathogens which can stay alive and multiply in professional and nonprofessional phagocytes. Immunity against Brucella melitensis involves antigen-specific CD4(+) and CD8(+) T-cells activation and humoral immune responses. Due to negative aspects of live attenuated vaccines, much attention has been focused on finding Brucella-protective antigens to introduce them as potential subunit vaccine candidates. MATERIALS AND METHODS: A chimeric gene encoding trigger factor (TF), Omp31(48-74) and BP26(87-111) fragments (TOB) from B. melitensis was successfully cloned, expressed in Escherichia coli BL21-DE3 and purified by Ni-NTA agarose column. Antibodies to recombinant TOB (rTOB) have been investigated in Brucella-infected human sera and a pool serum prepared from B. melitensis-vaccinated rabbits. RESULTS: Our results showed that the immunized rabbit pool serum strongly reacted with rTOB. In addition, antibodies against rTOB were detectable in 76.5% of sera obtained from infected patients. CONCLUSION: These findings suggest that rTOB may provide a potential immunogenic candidate which could be considered in future vaccine studies.

Quantification of sperm specific mRNA transcripts (PRM1, PRM2, and TNP2) in teratozoospermia and normozoospermia: New correlations between mRNA content and morphology of sperm.

Sperm mRNAs could be used as a predictor of fertilization capacity since the transcriptional profile of a gamete is critical for the production of viable human sperm. The aim of this study was to determine if PRM1, PRM2, and TNP2 transcripts in spermatozoa from normozoospermic and teratozoospermic men correlate with sperm morphology and/or assisted-reproduction outcomes. Human ejaculates were collected from 138 men referred to an infertility clinic, and were separated in two groups, teratozoospermic (n =72) and normozoospermic (n =66), based on World Health Organization criteria (2010). Chromomycin A3 and analine blue staining were used to evaluate protamination and chromatin integrity, respectively. Quantitative reverse-transcriptase PCR was performed for PRM1, PRM2, and TNP2. This analysis revealed significantly higher PRM1 and PRM2 mRNA copy numbers in normozoospermic versus teratozoospermic samples (P < 0.001). In contrast, TNP2 transcript abundance was significantly higher in teratozoospermic versus normozoospermic samples (P < 0.001) and positively correlated with sperm-head defects (P < 0.05). Sperm-tail defects negatively correlated (P < 0.05) with both PRM1 and PRM2 transcripts in normozoospermic samples. No significant differences were observed between the two groups when comparing transcript levels to the outcome of intracytoplasmic sperm injection cycles (P > 0.05), and a normal PRM1/PRM2 mRNA ratio (∼1) was observed in more than 70% of successful cycles. Thus, the quantity of PRM1, PRM2, and TNP2 transcripts and the PRM1/PRM2 mRNA ratio affect spermiogenesis, sperm morphology, and the function of mature human sperm. These mRNAs could therefore be used as biomarkers for the diagnosis of male infertility.