Impact assessment and investigation of factors associated with herpesviruses viremia in the first year of renal transplantation.

The increased risk for opportunistic infections after a renal transplant requires monitoring of viral infections to avoid future complications. Our goal was to investigate the impact and factors associated with Epstein-Barr virus (EBV), human cytomegalovirus (HCMV) and human herpesvirus type 6 (HHV-6) viremia in renal transplant recipients. Whole blood samples were collected monthly from 82 patients during the first semester and then quarterly up to 1 year after transplantation. EBV, HCMV, and HHV-6 were detected and quantified by TaqMan real-time polymerase chain reaction. The results showed that EBV and HCMV viremia were detected in 32 patients (39% each), while HHV-6 viremia in only 3 patients (3.7%). EBV was significantly associated with age (P = .050), thymoglobuline induction (P = .019), mTOR inhibitor-based therapy (P = .003), and female gender (P = .044). HCMV was significantly associated with basiliximab induction (P = .015), mycophenolate mofetil (MMF)-based therapy (P = .003) and allograft acute rejection (P = .033). Moreover, HCMV-disease was correlated with MMF-based therapy (P = .021) and female gender (P = .003). In conclusion, EBV and HCMV viremia were associated with different immunosuppressive induction and maintenance strategies. Additionally, higher HCMV viremia (> 10 4 copies/mL) was related to acute allograft rejection.

Investigation of three oncogenic epitheliotropic viruses shows human papillomavirus in association with non-melanoma skin cancer.

Non-melanoma skin cancers (NMSC) share similar risk factors with other virus-related cancers, despite the lack of proved causal association between viral infection and NMSC development. We investigated the presence of Merkel cell polyomavirus (MCPyV), Epstein-Barr virus (EBV), and human papillomavirus (HPV) DNA in 83 NMSC fresh-frozen and 16 non-cancerous skin biopsies and evaluated viral infection according to demographical data, histopathological diagnosis, and ultraviolet exposure. Our results showed that 75% of NMSC biopsies were positive for at least one out of three viruses, whereas only 38% of non-cancerous skin biopsies were positive (p = 0.02). Notably, HPV detection was frequent in NMSC (43%) and nearly absent (one sample, 6.7%) in non-cancerous biopsies (p = 0.007). MCPyV was associated with sites of higher exposure to ultraviolet radiation (p = 0.010), while EBV was associated with a compromised immune system (p = 0.032). Our study showed that HPV was strongly associated with NMSC while EBV and MCPyV with other risk factors. Though further studies are required to elucidate the role of viral infection in NMSC development and management, this study supports the possible role of oncogenic viruses in skin cancers, especially HPV.

Detection of Merkel cell polyomavirus in oral samples of renal transplant recipients without Merkel cell carcinoma.

Merkel cell carcinoma (MCC) is a rare but aggressive neuroendocrine cancer, with approximately 80% of cases associated with Merkel cell polyomavirus (MCPyV). The lack of information concerning its occurrence in non-MCC immunosuppressed populations led to the investigation of MCPyV DNA in saliva and oral biopsies from 60 kidney allograft recipients and 75 non-transplanted individuals (control group). In contrast to herpesviruses, which was also investigated (CMV, HHV-6A, and B, HHV-7) MCPyV was detected predominantly in patients with oral lesions (gingivitis and/or periodontitis) of both transplanted and non-transplanted groups (P=0.016) and in the saliva of the transplanted group (P=0.009). MCPyV co-detection with CMV (P=0.048), and HHV-6 (P=0.020) in the saliva of transplanted patients requires further investigation on a possible role of co-infection.

Human Polyomaviruses: The Battle of Large and Small Tumor Antigens.

About 40 years ago, the large and small tumor antigens (LT-Ag and sT-Ag) of the polyomavirus (PyVs) simian vacuolating virus 40 have been identified and characterized. To date, it is well known that all the discovered human PyVs (HPyVs) encode these 2 multifunctional and tumorigenic proteins, expressed at viral replication early stage. The 2 T-Ags are able to transform cells both in vitro and in vivo and seem to play a distinct role in the pathogenesis of some tumors in humans. In addition, they are involved in viral DNA replication, transcription, and virion assembly. This short review focuses on the structural and functional features of the HPyVs' LT-Ag and sT-Ag, with special attention to their transforming properties.

Clinical aspects and weight gain reduction in swine infected with porcine circovirus type 2 and torque teno sus virus in Brazil.

Simultaneous Porcine circovirus type 2 (PCV-2) and Torque teno sus virus (TTSuV) infections have been reported around the world, generally linked to severe infections. In the present study, 257 swine plasma samples from 31 swine herds located in Brazil, were PCR screened for PCV-2 and TTSuV-1/2 and correlated with clinical data. PCV-2 was detected in 25%, followed by 38.1% and 42.4% of TTSuV-1 and TTSuV-2, respectively. Co-infections of two or three viruses were found in 32.3% of samples. PCV-2 was more frequently detected in the growing (p=0.030) and finishing phases (p=0.0005) while TTSuV-2 in the nursery (p=0.009). Only TTSuV-1 was statistically associated to clinical disease (multiple signs), in combination or not with PCV-2 or TTSuV-2 (p=0.015). PCV-2/TTSuV co-infections were more frequently related to weight gain reduction in comparison to mono-infections (p=0.049) and no-infections (p=0.027), and also in animals with (p=0.011) or without (p=0.037) clinical signs, being the nursery the most affected phase (p=0.025). Our results uphold the pathogenic potential of TTSuV in naturally infected pigs and the clinical/economical impact of this agent, especially in co-infections. Studies addressing the physiopathological mechanisms of simultaneous infections are needed.

ASSOCIATION OF EPSTEIN-BARR VIRUS (EBV) BUT NOT HUMAN PAPILLOMAVIRUS (HPV) WITH GINGIVITIS AND/OR PERIODONTITIS IN TRANSPLANTED INDIVIDUALS.

The aim of this study was to investigate the association of EBV and HPV with gingivitis and/or periodontitis according to the immunologic status. To this end, 74 oral biopsies from transplanted and non-transplanted individuals with the abovementioned oral manifestations were submitted to a screening by PCR for both viruses. According to the results, EBV was strongly associated with gingivitis and/or periodontitis in transplanted individuals (p = 0.011) but not HPV (p = 0.766). EBV-HPV co-detections did not enhance the presence of tissue injury as well. Although a causal relationship was not investigated in this study, the higher frequency of these two oncoviruses in lesion tissues must be investigated in follow-up studies, especially among immunocompromised individuals.