A globally applicable PCR-based detection and discrimination of BK and JC polyomaviruses

BKV and JCV belong to the Polyomaviridae family and are opportunistic agents associated with complications in immunocompromised individuals. Although a single screening assay for both viruses would be convenient, the diversity of BKV and JCV serotypes and genotypes is a methodological challenge. In this paper, we developed a PCR method able to detect and segregate BKV and JCV, despite these genetic discrepancies. A duplex semi-nested PCR (duplex snPCR) was designed to target a conserved region (639nt-1516nt) within the VP2 gene. In the first PCR, a primer set common to all BKV and JCV serotypes/ genotypes was used, followed by a semi-nested PCR with internal primers for BKV and JCV segregation. The limit of detection of the duplex snPCR was as low as 10 copies of BKV or JCV plasmids/µL. Specific products were observed when JCV and BKV plasmids were mixed in the same reaction. In field sample testing, the duplex snPCR detected and distinguished both viruses in different biological samples. Results were confirmed by Sanger’s sequencing. The geographical complexity of BKV and JCV serotypes and genotypes imposes limits to a simple and universal method that could detect each virus. However, we describe here a sensitive and reliable PCR technique for BKV and JCV diagnosis that overcomes these limitations and could be universally applied

A globally applicable PCR-based detection and discrimination of BK and JC polyomaviruses

ABSTRACT BKV and JCV belong to the Polyomaviridae family and are opportunistic agents associated with complications in immunocompromised individuals. Although a single screening assay for both viruses would be convenient, the diversity of BKV and JCV serotypes and genotypes is a methodological challenge. In this paper, we developed a PCR method able to detect and segregate BKV and JCV, despite these genetic discrepancies. A duplex semi-nested PCR (duplex snPCR) was designed to target a conserved region (639nt-1516nt) within the VP2 gene. In the first PCR, a primer set common to all BKV and JCV serotypes/ genotypes was used, followed by a semi-nested PCR with internal primers for BKV and JCV segregation. The limit of detection of the duplex snPCR was as low as 10 copies of BKV or JCV plasmids/μL. Specific products were observed when JCV and BKV plasmids were mixed in the same reaction. In field sample testing, the duplex snPCR detected and distinguished both viruses in different biological samples. Results were confirmed by Sanger's sequencing. The geographical complexity of BKV and JCV serotypes and genotypes imposes limits to a simple and universal method that could detect each virus. However, we describe here a sensitive and reliable PCR technique for BKV and JCV diagnosis that overcomes these limitations and could be universally applied

Prevalence, risk factors and genotypes of hepatitis B infection among HIV-infected patients in the State of MS, Central Brazil

Objectives:A cross-sectional study on prevalence of HBV and HDV infection, risk factors and genotype distribution of HBV infection was conducted among 848 HIV-infected patients in Mato Grosso do Sul, Central Brazil.Methods:Serum samples of 848 participants were tested for hepatitis B surface antigen (HBsAg), hepatitis B core antibody (anti-HBc) and hepatitis surface antibody (anti-HBs). HBsAg positive samples were tested for anti-HBc IgM, HBeAg, anti-HBe, anti-HCV, and total anti-HDV. HBsAg and anti-HBc positive were subjected to DNA extraction. Viral DNA was amplified by semi-nested PCR for the regions pre-S/S and then purified and genotyped/subgenotyped by direct sequencing. Student's t-test, chi-square test and Fisher's exact test were used to compare variables and to evaluate association between HBV positivity (defined as anti-HBc and/or HBsAg positivity) and risk factors.Results:Among the 848 HIV infected patients investigated 222 had serological markers of HBV infection. The prevalence rate of HIV-HBV coinfection was 2.5% (21/848; 95% CI: 1.4–3.5%); 484 (57.1%) patients were susceptible for HBV infection. There were no cases of anti-HDV positive and only one (0.1%) anti-HCV-positive case among the HIV-HBV coinfected patients. Male gender, increasing age, family history of hepatitis, use of illicit drug, and homosexual activity were independent factors associated with HBV exposure. The phylogenetic analysis based on the S gene region revealed the presence of genotypes D (76.9%), F (15.4%) and A (7.7%) in the study sample.Conclusion:This study demonstrates the low prevalence of HIV-HBV infection and also highlights the need for early vaccination against HBV as well as testing for HBV, HCV and HDV in all HIV-infected individuals