Quantification of human polyomaviruses MCPyV and HPyV6 in malignant and non-malignant skin lesions

Abstract Background: Human Polyomaviruses such as MCPyV and HPyV6 are frequently found as part of healthy skin microbiota and have been associated with Merkel cell carcinoma (MCC), pruritic and dyskeratotic dermatoses, respectively. Their presence in other types of skin conditions varies greatly depending on lesion type and population. Objectives: To analyse comparatively the presence of MCPyV and HPyV6 in nonmelanoma skin cancers and healthy skin. Methods: The authors utilized qPCR techniques to quantify these pathogens in NMSC, premalignant diseases, and healthy skin of 87 patients. Results: MCPyV was detected in over 40% of samples, while HPyV6 was in 9.6%. MCPyV load was higher in squamous cell carcinomas (SCC) compared to basal cell carcinomas (BCC) (p = 0.016) and HPyV6 showed a higher percentage of infected cells in areas of low solar exposure as well as normal skin (p = 0.012). A fair agreement (kappa = 0.301) was found between MCPyV detection in lesions and their respective perilesional skin, indicating a random process of local dissemination of the virus. Study limitations: The lack of a larger sampling of different lesion types and protein expression analyses limits the correlation findings. Conclusions: This is the first report of HPyV6 detection in the healthy skin of a Brazilian population, but the role of both polyomaviruses in NMSC has yet to be demonstrated.

Quantification of human polyomaviruses MCPyV and HPyV6 in malignant and non-malignant skin lesions.

BACKGROUND: Human Polyomaviruses such as MCPyV and HPyV6 are frequently found as part of healthy skin microbiota and have been associated with Merkel cell carcinoma (MCC), pruritic and dyskeratotic dermatoses, respectively. Their presence in other types of skin conditions varies greatly depending on lesion type and population. OBJECTIVE: To analyse comparatively the presence of MCPyV and HPyV6 in nonmelanoma skin cancers and healthy skin. METHODS: The authors utilized qPCR techniques to quantify these pathogens in NMSC, premalignant diseases, and healthy skin of 87 patients. RESULTS: MCPyV was detected in over 40% of samples, while HPyV6 was in 9.6%. MCPyV load was higher in squamous cell carcinomas (SCC) compared to basal cell carcinomas (BCC) (p=0.016) and HPyV6 showed a higher percentage of infected cells in areas of low solar exposure as well as normal skin (p=0.012). A fair agreement (kappa=0.301) was found between MCPyV detection in lesions and their respective perilesional skin, indicating a random process of local dissemination of the virus. STUDY LIMITATIONS: The lack of a larger sampling of different lesion types and protein expression analyses limits the correlation findings. CONCLUSION: This is the first report of HPyV6 detection in the healthy skin of a Brazilian population, but the role of both polyomaviruses in NMSC has yet to be demonstrated.

Refractory pemphigus foliaceus associated with herpesvirus infection: case report.

Pemphigus foliaceus (PF) is an autoimmune disease characterized by blistering of the skin. Infections caused by members of the herpesviridae family have been suggested as a possible triggering factor for pemphigus vulgaris (PV), but not for PF. The present study aimed to investigate the presence of Human herpesvirus (types 1, 2, 3) in corticosteroid refractory skin lesions from a patient with PF, by a Polymerase chain reaction (PCR) assay. The sample collected from cutaneous blisters has tested positive for herpes simplex virus type 1 (HSV1) after sequence analysis of the amplified viral genomic segment. The study concluded that when PF patients present corticosteroid or immunosuppressants refractory lesions, herpetic infection should be considered.

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.

Phylogenetic and structural analysis of merkel cell polyomavirus VP1 in Brazilian samples.

Our understanding of the phylogenetic and structural characteristics of the Merkel Cell Polyomavirus (MCPyV) is increasing but still scarce, especially in samples originating from South America. In order to investigate the properties of MCPyV circulating in the continent in more detail, MCPyV Viral Protein 1 (VP1) sequences from five basal cell carcinoma (BCC) and four saliva samples from Brazilian individuals were evaluated from the phylogenetic and structural standpoint, along with all complete MCPyV VP1 sequences available at Genbank database so far. The VP1 phylogenetic analysis confirmed the previously reported pattern of geographic distribution of MCPyV genotypes and the complexity of the South-American clade. The nine Brazilian samples were equally distributed in the South-American (3 saliva samples); North American/European (2 BCC and 1 saliva sample); and in the African clades (3 BCC). The classification of mutations according to the functional regions of VP1 protein revealed a differentiated pattern for South-American sequences, with higher number of mutations on the neutralizing epitope loops and lower on the region of C-terminus, responsible for capsid formation, when compared to other continents. In conclusion, the phylogenetic analysis showed that the distribution of Brazilian VP1 sequences agrees with the ethnic composition of the country, indicating that VP1 can be successfully used for MCPyV phylogenetic studies. Finally, the structural analysis suggests that some mutations could have impact on the protein folding, membrane binding or antibody escape, and therefore they should be further studied.

Genetic and structural analysis of polyomavirus BK T-antigens reveal a higher density of mutations at inter-domain and hexamerization regions, regardless the status of infection.

Polyomavirus BK (BKPyV) T-antigens (large and small tumor antigens, or Lt-ag and st-ag, respectively), control key aspects of viral replication and are able to regulate cell cycle, promoting cell proliferation. However, the structural effects of genetic mutations on T-antigens are poorly investigated. In this study, 214 sequences of T-antigens from individuals with different BKPyV infections (16 renal transplant with nephropathy; 78 asymptomatic renal transplant; 24 hematopoietic stem cell transplant with hemorrhagic cystitis; 96 healthy non-transplant), were analyzed from the genetic and structural standpoints. We found a high concentration of non-synonymous mutations at inter-domains and hexamerization regions of both proteins, being five of them under positive selection in the Lt-ag but none in the st-ag. The in silico analysis indicated that two mutations, located at positions 164 in the st-ag and 592 in the Lt-ag, would significantly affect the interaction with PP2A and p53 cell targets, respectively, although they were not associated to a specific clinical status. No mutations were detected on the J-domains or at the ATPase motif. In sum, the profile of the mutations found seem not to be associated to increased morbidity. This is the first work to analyze structural modifications on T-antigens in different BKPyV infections, and managed to map conserved and variable regions of the T-antigens, which will be helpful for the study of new antiviral drugs.

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.

Acyclovir susceptibility of herpes simplex virus isolates from transplanted and nontransplanted patients in Rio de Janeiro, Brazil.

Herpes simplex virus (HSV) is prevalent worldwide and known as a notorious opportunistic pathogen ofimmunocompromised patients. During the course of HSV treatment, acyclovir (ACV)-resistant HSV strains may emerge, causing many clinical complications. Because few studies in this area showing the presence and/or frequency ofACV-resistant HSV are available, the authors evaluated the sensitivity of HSV isolated from 3 hematopoietic stem cell transplant recipients and 24 normal patients observed in a University Hospital in Rio de Janeiro, Brazil. Twenty-seven HSV isolated in VERO cells and typed by the direct immunofluorescence assay were tested for their susceptibility to various concentrations ofACV by the dye-uptake method. The susceptibility of the HSV strains was expressed as ED50 (the concentration of drug reducing viral cytophatic effect by 50%). The sensitivity to ACV by the dye-uptake assay revealed that 25 samples (92.6%) were sensitive to ACV concentrations < 1.5 microg/mL. One sample (3.7%) showed intermediate susceptibility (1.56 microg/mL) and one other sample (3.7%) showed resistance to ACV concentrations above the cut-off (2 microg/mL). The presence of resistance in immunocompetent patients could be the result of the frequent use of ACV for the treatment of recurrence. The routine use of HSV susceptibility testing is fundamental in the clinical suspicion of resistance not only for the knowledge of the incidence of HSV resistance in Brazil, but also to understand the mechanism of HSV resistance.

Diagnóstico laboratorial da infeccão pelo vírus herpes simples (HSV) em pacientes transplantados e não-transplantados / Laboratorial diagnosis of herpes simplex virus infection (HSV) in transplanted and non-transplanted patients

INTRODUÇAO: O vírus herpes simples (HSV) é dividido em dois sorotipos (HSV-1 e HSV-2) responsáveis, respectivamente, pelos herpes labial e genital. Embora a infeccão pelo HSV tenha um curso rápido, esse agente está freqüentemente relacionado a complicacões no tratamento de pacientes imunocomprometidos, como indivíduos transplantados, na condicão de agente oportunista. OBJETIVOS: Comparar e avaliar o uso de três técnicas atuais para diagnóstico de HSV em pacientes transplantados e não-transplantados. MATERIAL E MÉTODOS: Oitenta e quatro amostras clínicas consecutivas provenientes de 47 indivíduos transplantados e 37 não-transplantados foram coletadas de junho de 2001 a julho de 2002, sendo, simultaneamente, submetidas a nested multiplex reacão em cadeia da polimerase (PCR) (nmPCR), multiplex PCR (mPCR) e isolamento viral (IV) em células vero. RESULTADOS: Das amostras, 33,3 por cento (28/84) foram positivas para o HSV por IV, 34,5 por cento(29/84) por mPCR e 42,8 por cento (36/84) por nmPCR. Pela técnica de imunofluorescência direta (IFD), 85,7 por cento (24/28) das amostras foram caracterizadas como HSV-1, 86,2 por cento (25/29) pelo mPCR e 88,9 por cento(32/36) pelo nmPCR. Foram caracterizadas como HSV-2 pelas três técnicas empregadas 4,8 por cento(4/84) das amostras. Não houve diferenca significante de deteccão entre as técnicas de diagnóstico do HSV (p = 0,38), embora o nmPCR tenha detectado mais amostras de pacientes transplantados (p = 0,05). CONCLUSAO: Apesar do desempenho similar entre as técnicas, o nmPCR se mostrou ferramenta útil para pacientes transplantados ou para aqueles sob tratamento antiviral, onde é esperada baixa carga viral em suas amostras.

Herpes simples virus ophthalmic disease induced using two different methods of mice inoculation

Two different procedures for inoculation of HSV on corneas of balb/c mice were evaluated. The first was by the use of HSV suspensions directly on the corneas and the other was after corneal scarification. Animals by this later method presented greater morbidity and mortalitythan those of first group, suggesting than inoculation of HSV without scarification of the cornea should be the method of choice for the study of HSV ophthalmic infection. This model showed also be an efficient experimental system to testing antiviral drugs.

Exposiçäo à infecçäo pelo vírus da hepatite B em trabalhadores da coleta de lixo domiciliar e hospitalar no Município do Rio de Janeiro / Hepatitis B morbidity among municipal and hospital waste collection workers from Rio de Janeiro city, Brazil

Investiga a morbidade de hepatite B entre trabalhadores da coleta de resíduos domiciliares e hospitalares.A tendência de estabelecer sistemas diferenciados de coleta e tratamento para os resíduos hospitalares tem elevado os custos dos serviços e é questionada por diversos autores. As amostras de sangue foram coletadas de 155 trabalhadores da coleta domiciliar e 31 trabalhadores da coleta de resíduos hospitalares, empregados da Companhia Municipal de Limpeza Urbana do Rio de Janeiro. A prevalência de HBV foi de 14,2 por cento e 12,9 por cento para trabalhadores da coleta domiciliar e hospitalar. Não houve diferença com significância estatística entre os dois grupos estudados sendo isto, um indicador da inexistência de diferenças entre os dois tipos de resíduos com referência à exposição à infecção por HBV