Bac to Bac System Efficiency for Preparing HPV Type 16 Virus-Like Particle Vaccine

Today, the human papillomavirus (HPV) L1 protein is the main target in the construction of prophylactic HPV vaccines. The production of virus-like particles (VLPs) that closely resemble the natural structure of the HPV16 virus and induce high levels of virus-neutralizing antibodies in animals and humans is facilitated by the expression of HPV16-L1 protein in eukaryotic cells. The Bac-to-Bac system has been previously used to produce high levels of recombinant proteins. In this study, we utilized this expression system to generate HPV16-L1 VLPs in Spodoptra frugipedra (Sf9) insect cells. The wild-type L1 gene of papillomavirus type 16 was selected from Gene Bank and placed in bacmid structure after codon optimization using pFast Bac vector. The recombinant baculovirus containing HPV-16/L1 gene was then provided using the Bac-to-Bac system. It should be mentioned that the vector was transfected into the Sf9 cell. The cells were then lysed and the expression of L1 protein was revealed by SDS-PAGE and confirmed by Western Blot. The L1 purification was performed through Ni-NTA chromatography. The VLP formation of papillomavirus L1 protein was visualized by transmission electron microscopy. The expressed recombinant L1 was ~60 KD on SDS-PAGE which was identified in western blot by a specific anti-L1 monoclonal antibody. The electron microscopy confirmed the assembly of VLPs. Results of this study showed that the production of this protein at the industrial level can be optimized using a baculovirus/Sf9 system. The characteristics and advantages of this system are promising and it is a suitable candidate for protein synthesis.

Association between ABO blood groups and rhesus antigen and susceptibility to COVID-19 in the Yazd hospital

Blood group antigens are one of the most important antigens in humans that have an impact on susceptibility to disease and may be used as a prognosis factor in different diseases such as COVID-19. The study aimed to investigate the relationship between ABO blood groups and Rhesus antigen and susceptibility to COVID-19. The clinical data of 398 subjects were used in the investigation collected from 148 cases vs. 250 controls. This information was obtained from Shahid Sadoughi Hospital of Yazd (IRAN) University. Blood groups and outcomes were assessed using statistical tests for four populations: COV + vs. COV− and COV +/deceased vs. COV +/live. Out of a total of 148 COVID-19 patients, 80 (54/1%) were male, 68 (45/9%) were female. Among these patients, 33 (22/6%) had type A+, 44 (30/1%) had type B+, 13 (8/9%) had type AB+, and 36 (24/7%) had type O+. On the other hand, out of 148 patients, 126 (86/3%) had positive blood types, and 20 (13/7%) had negative blood types. As a result, no significant difference was found in the relationship between ABO blood groups and RH type and susceptibility to COVID-19 (p-value = 0.392 and p-value = 0.847, respectively). Other data showed a significant difference between patients group with other parameters such as age (p-value<0.001) and gender (p-value<0.001). Although in this study there was no association between blood type and RH type with COVID-19, findings of the association between age and gender can confirm the results of previous studies.