微生物学

Multiple viruses can co-infect the genital tract, modifying the immunologic and virologic milieu and possibly playing a role in viral transmission and pathogenesis. The aim of our studies has been to understand the complex relationships between HIV-1 RNA, and multiple human herpesviruses known to frequently replicate in the genital tract of HIV-infected men (i.e. cytomegalovirus [CMV], Epstein Bar virus [EBV], herpes simplex virus [HSV] types 1 and 2, and human herpesviruses [HHV] 6, 7 and 8) (Gianella et al., 2013a; Gianella et al., 2013b; Gianella et al., 2013c; Gianella et al., 2014). This protocol was designed to collect and process male genital secretion (GS), and to isolate and further quantify HIV RNA and DNA of seven HHV from seminal plasma using quantitative real time PCR technology.

Hepatitis E virus (HEV) is one of the main causes of acute hepatitis worldwide. Infections are particularly severe in pregnant women and chronic hepatitis E is known to occur in immunocompromised patients. Current therapy (ribavirin or pegylated alpha interferon) has severe side effects and cannot be employed in all patients. In order to evaluate potential new inhibitors of HEV replication, a virus yield assay can be employed in which the amount of viral RNA progeny released into the culture medium is quantified by reverse-transcription quantitative PCR (RT-qPCR) (Debing et al., 2014).

Most recently a novel avian-origin influenza A (H7N9) virus emerged in China and has been associated with lots of human infection and fatal cases. Molecular diagnostic methods are thus urgently needed in public health laboratories. We developed a SYBR green-based one-step real time reverse transcription-PCR (RT-PCR) to detect the novel H7N9 virus.

This is a protocol to detect HIV-1 reverse transcription products in cytoplasmic and nuclear fractions of cells infected with VSV-G-pseudotyped envelope-defective HIV-1. This protocol can also be extended to HIV-1 with regular envelope.

Quantification of retroviral reverse transcriptase activity in retrovirus containing supernatant by quantitative reverse transcription PCR as a method for titration of HIV, lenti- and retroviral vectors is described here.. The procedure was optimized for use with LightCycler 480 (Roche, Vilvoorde, Belgium) and ABI 7300 real-time PCR system (reagents and procedures that are system specific will be marked accordingly in the protocol).

Formation of viral particles and packaging of genomic retroviral RNA into these particles are important steps in the late phase of the viral replication cycle. The efficiency of the incorporation of viral or cellular RNAs into viral particles can be studied using a quantitative Reverse Transcriptase-PCR (RT-qPCR)-based approach. After isolation of cytoplasmic RNA from either infected or transfected cells and extraction of virus particle-associated RNA, specific RNA levels present in both fractions are determined. The ratio of virion-associated and cytoplasmic RNA defines the encapsidation efficiency (Brandt et al., 2007; Blissenbach et al., 2010; Grewe et al., 2012).