Human papillomavirus (HPV) E6 and E7 oncoproteins play a crucial role in HPV-related diseases, such as cervical cancer, and can be used as ideal targets for therapeutic vaccines. Human leukocyte antigen (HLA) participates in the immune response to block HPV infection and invasion by its target/recognition function. HPV-33 and HPV-58 are highly prevalent among Chinese women. Therefore, it is of great significance to study the E6 and E7 region-specific gene polymorphisms of HPV-33 and HPV-58 in Southwest China and to identify ideal epitopes for vaccine design. Both HPV-33 and HPV-58 belong to α-9 genus HPV and are highly homologous, so their correlations are included in our research. To study the E6 and E7 variations and polymorphisms of HPV-33 and HPV-58 in Southwest China, we collected samples, extracted and sequenced DNA, and identified variants. Nucleotide sequences were translated into amino acids by Mega 6.0 software. The physical/chemical properties, amino acid-conserved sequences and secondary structure of protein sequences were analysed by the Protparam server, ConSurf server and PSIPRED software. The T and B cell epitopes of the E6/E7 reference and variant sequences in HPV-33 and HPV-58 were predicted by the Immune Epitope Database (IEDB) analysis server and the ABCpred server, respectively. Five and seven optimal HLA-I restricted T cell epitopes were selected from HPV-33 and HPV-58 E6, respectively, and these optimal epitopes are mainly located in 41-58EVYDFAFADLTVVYREGN of HPV-33 E6 and 40-60SEVYDFVFADLRIVYRDGNPF of HPV-58 E6. Six optimal HLA-I-restricted T cell epitopes were selected from HPV-33 and HPV-58 E7, and these epitopes are mainly located in 77-90RTIQQLLMGTVNIV of HPV-33 E7 and 78-91RTLQQLLMGTCTIV of HPV-58 E7. HPV-33/HPV-58 E6/E7 gene polymorphisms and T/B cell epitopes of their reference and variant sequences were studied, and candidate epitopes were selected by bioinformatics techniques for therapeutic vaccine design for people in Southwest China. This study was the first to investigate the correlation of epitopes between HPV-33 and HPV-58. After experimental validation, these selected epitopes will be employed to induce a wide range of immune responses in heterogeneous HLA populations.

Cervical cancer is associated with infection by certain subtypes of human papillomavirus (HPV). The L1 protein comprising HPV vaccine formulations elicits high-titre neutralizing antibodies and confers protection against specific HPV subtypes. HPV L2 protein is an attractive candidate for cross-protective vaccines. HPV-33 and HPV-58 are very prevalent among Chinese women. To study the gene intratypic variations and polymorphisms of HPV-33 and HPV-58 L1/L2 in Sichuan China, HPV-33 and HPV-58 L1 and L2 genes were sequenced and compared with other genes submitted to GenBank. Phylogenetic trees were constructed by maximum-likelihood and the Kimura 2-parameters methods (MEGA 6). The secondary structure was analyzed by PSIPred software, and HPV-33 and HPV-58 L1 homology models were created by SWISS-MODEL software. The selection pressures acting on the L1/L2 genes were estimated by PAML 4.8. Among 124 HPV-33 L1 sequences 20 single nucleotide mutations were observed included 8/20 non-synonymous and 12/20 synonymous mutations. The 101 HPV-33 L2 sequences included 12 single nucleotide mutations comprising 7/12 non-synonymous and 5/12 synonymous mutations. The 223 HPV-58 L1 sequences included 32 single nucleotide mutations comprising 9/32 non-synonymous and 23/32 synonymous mutations. The 201 HPV-58 L2 sequences comprised 26 single nucleotide mutations including 9/26 non-synonymous and 17/26 synonymous mutations. Selective pressure analysis showed that most of the common non-synonymous mutations showed a positive selection. HPV-33 and HPV-58 L2 were more stable than HPV-33 and HPV-58 L1. HPV-33 and HPV-58 L2 were better candidates as clinical diagnostic targets compared with HPV-33 and HPV-58 L1. Clinical diagnostic probes and second-generation polyvalent vaccines should be designed on the basis of the unique sequence of HPV-33 and 58 L1/L2 variations in Sichuan, to improve the accuracy of clinical detection and the protective efficiency of vaccines.

We investigated azoospermia region microdeletions in male infertility patients with Klinefelter syndrome (KFS), as well as the association between azoospermia symptoms in patients with KFS and Y chromosome microdeletion polymorphisms. A total of 111 cases with male infertility confirmed to have KFS (47, XXY) and 94 fertile men were included in this study. Peripheral blood was drawn and DNA was extracted from these samples. Multiplex polymerase chain reaction was performed to screen the partial deletions of 25 sequence-tagged sites on the Y chromosome. In 111 cases with KFS, 1 case contained the AZFb+d+c deletion. The Gr/Gr deletion was identified in 12 KFS cases and 5 control cases. In addition, the b2/b3 deletion was identified in 13 KFS cases and 6 control cases. There were no significant differences in phenotype and genotype of the 2 partial AZFc deletions between patients and controls (P > 0.05). Our results suggest that patients with KFS may also have Y chromosome microdeletions to varying degrees and that the gr/gr deletion and b2/b3 deletion may not play a role in the susceptible genetic background of azoospermia in patients with KFS in the Sichuan population.

Background: Human papillomavirus (HPV) is one of the most common sexually transmitted viruses. Data about HPV infection in Guizhou is limited. Methods: 56,768 cervical samples were collected and genotyped for 15 main high risk and 6 main low risk HPV types. Results: 16.95% (9623/56768) of samples were HPV positive; 90.70% (8728/9623) of HPV positive women were infected by high risk HPV. High risk and high risk mix infection (1458; 70.85%) was the most common mix HPV infection type. The highest HPV detection rate was found in age group 41–45 years old (detection rate = 17.89%) (χ2 = 204.77; P < 0.001); the highest within-group HPV infection rates were found in the ≤20 (25.62%) and ≥ 61 (24.67%) years old age groups, the lowest within-group HPV infection rate was found in the 31–35 years old age group (15.02%). The highest mix infection proportions were found in the ≥61 (36.06%) and ≤ 20 (33.63%) years old age groups (χ2 = 111.21; P < 0.001), the lowest mix infection proportion was found in the 41–45 (17.42%) years old age group. The highest high risk infection proportions were found in the 26–30 (92.98%), ≥61 (92.68%), and 36–40 (92.16%) years old age groups (χ2 = 31.72; P < 0.001), the lowest high risk infection proportion was found in the ≤20 (84.96%) years old age group. HPV infection rates varied with seasons in Guizhou. Conclusions: Characteristics of HPV distribution in Guizhou were identified. There were significant differences in HPV distribution among age groups, prevention strategies should be adjusted according to the characteristics.