Identification of a new polyomavirus in distinct human populations and tissues.

Several human polyomaviruses (HPyVs) have been described in the last 15 years. This work aimed to characterize a novel HPyV with cutaneous tropism. Swabs of healthy skin (forehead) of 75 immunocompetent individuals from Argentina were screened for HPyV through sequence amplification techniques. Publicly available metagenomic data sets were also analyzed. A previously unknown polyomavirus sequence was detected in two skin swab samples. A nearly identical sequence was detected in public data sets representing metagenomic surveys of human skin and feces. Further analyses showed that the new polyomavirus diverges from its nearest relative, human polyomavirus 6 (HPyV6), by 17.3%-17.7% (in nucleotides for the large T antigen), which meets criteria for a new species designation in the genus Deltapolyomavirus. The screening also revealed more distant HPyV6 relatives in macaque genital and chimpanzee fecal data sets. Since polyomaviruses are generally thought to cospeciate with mammalian hosts, the high degree of similarity to HPyV6 suggests the new polyomavirus species is human-tropic. Therefore, a novel polyomavirus was identified and characterized from samples of distinct populations and tissues. We suggest the common name human polyomavirus 16 (HPyV16).

Genetic variation in the E6 and E7 genes of human papillomavirus type 16 in northeastern Argentina.

The province of Misiones is considered a region with a high mortality rate due to cervical cancer (CC). To gain insight into this problem, we explored the association between genetic variation in the E6 and E7 oncogenes of HPV16 and the risk of CC. We studied 160 women with cytological diagnoses of negative for intraepithelial lesion or malignity, low-grade squamous intraepithelial lesion, and high-grade squamous intraepithelial lesion/CC and a positive test for HPV16 infection. The genetic characterization of E6 and E7 genes was undertaken through PCR amplification and direct Sanger sequencing. Phylogenetic classification was conducted using Bayesian methods. To estimate the odds ratio (OR) for an association between genetic variants in the E6 and E7 genes and the risk of CC, we used ordinal logistic regression adjusted by age. The final data set comprised 112 samples. Diagnostic single-nucleotide polymorphisms (SNPs) and phylogenetic trees confirmed the presence of Lineage A (95.5%) and D (4.5%) in the samples. For the E6 gene, we identified eleven different sequences, with the most common ones being Lineage A E6 350G (58.9%) and E6 350T (37.5%). The E6 350G was associated with progression to HSIL/CC, with an OR of 19.41 (4.95-76.10). The E7 gene was more conserved than E6, probably due to the functional constraints of this small protein. Our results confirmed the association of the E6 350G SNP with a higher risk of developing CC. These data will contribute to understanding the biological bases of CC incidence in this region.

Mitochondrial DNA ancestry, HPV infection and the risk of cervical cancer in a multiethnic population of northeastern Argentina.

BACKGROUND: Misiones Province in northeastern Argentina is considered to be a region with a high prevalence of HPV infection and a high mortality rate due to cervical cancer. The reasons for this epidemiological trend are not completely understood. To gain insight into this problem, we explored the relationship between mitochondrial DNA (mtDNA) ancestry, HPV infection, and development of cervical lesions/cancer in women from the city of Posadas in Misiones Province. METHODS: Two hundred and sixty-one women, including 92 cases of patients diagnosed with cervical lesions and 169 controls, were analyzed. mtDNA ancestry was assessed through HVS1 sequencing, while the detection and typing of HPV infection was conducted through nested multiplex PCR analysis. Multivariate logistic regression was conducted with the resulting data to estimate the odds ratios (ORs) adjusted by socio-demographic variables. RESULTS: The study participants showed 68.6% Amerindian, 26.1% European and 5.3% African mtDNA ancestry, respectively. Multiple regression analysis showed that women with African mtDNAs were three times more likely to develop a cervical lesion than those with Native American or European mtDNAs [OR of 3.8 (1.2-11.5) for ancestry and OR of 3.5 (1.0-12.0) for L haplogroups], although the associated p values were not significant when tested under more complex multivariate models. HPV infection and the development of cervical lesions/cancer were significant for all tested models, with the highest OR values for HPV16 [OR of 24.2 (9.3-62.7)] and HPV-58 [OR of 19.0 (2.4-147.7)]. CONCLUSION: HPV infection remains a central risk factor for cervical cancer in the Posadas population. The potential role of African mtDNA ancestry opens a new avenue for future medical association studies in multiethnic populations, and will require further confirmation in large-scale studies.

Epstein-Barr virus load in transplant patients: Early detection of post-transplant lymphoproliferative disorders / Carga de virus Epstein-Barr en pacientes trasplantados: detección temprana de desórdenes linfoproliferativos postrasplante

High levels of circulating EBV load are used as a marker of post-transplant lymphoproliferative disorders (PTLD). There is no consensus regarding the threshold level indicative of an increase in peripheral EBV DNA. The aim of the study was to clinically validate a developed EBV quantification assay for early PTLD detection. Transversal study: paired peripheral blood mononuclear cells (PBMC), plasma and oropharyngeal lymphoid tissue (OLT) from children undergoing a solid organ transplant with (n = 58) and without (n = 47) PTLD. Retrospective follow-up: 71 paired PBMC and plasma from recipients with (n = 6) and without (n = 6) PTLD history. EBV load was determined by real-time PCR. The diagnostic ability to detect all PTLD (categories 1-4), advanced PTLD (categories 2-4) or neoplastic PTLD (categories 3 and 4) was estimated by analyzing the test performance at different cut-off values or with a load variation greater than 0.5 log units. The higher diagnostic performance for identifying all, advanced or neoplastic PTLD, was achieved with cut-off values of 1.08; 1.60 and 2.47 log EBV gEq/10(5) PBMC or 2.30; 2.60; 4.47 log gEq/10(5) OLT cells, respectively. EBV DNA detection in plasma showed high specificity but low (all categories) or high (advanced/neoplastic categories) sensitivity for PTLD identification. Diagnostic performance was greater when: (1) a load variation in PBMC or plasma was identified; (2) combining the measure of EBV load in PBMC and plasma. The best diagnostic ability to identify early PTLD stages was achieved by monitoring EBV load in PBMC and plasma simultaneously; an algorithm was proposed.

La carga alta del virus Epstein-Barr se utiliza como un marcador de desórdenes linfoproliferativos postrasplante (post-transplant lymphoproliferative disorders [PTLD]). El objetivo de este estudio fue validar clínicamente un ensayo de cuantificación del virus Epstein-Barr para la detección temprana de PTLD. Se efectuó un estudio transversal en el que se analizaron muestras pareadas de células mononucleares periféricas (CMP), de plasma y de tejido linfoide orofaríngeo de niños con trasplante de órgano sólido, con PTLD (n = 58) y sin PTLD (n = 47). En el seguimiento retrospectivo se incluyeron 71 muestras pareadas de CMP y de plasma de trasplantados, con PTLD (n = 6) y sin PTLD (n = 6). La carga viral se determinó por PCR en tiempo real. Se estimó la capacidad diagnóstica para detectar PTLD (categorías: todas vs. avanzadas vs. neoplásicas) analizando diferentes valores de corte o una variación de carga mayor de 0,5 logaritmos. El mayor desempeño diagnóstico para identificar todos los PTLD, los avanzados y los neoplásicos, se obtuvo con valores de corte de 1,08; 1,60 y 2,47 log copias/10(5) en CMP y de 2,30; 2,60 y 4,48 log copias/10(5) en células de tejido linfoide orofaríngeo, respectivamente. La detección del ADN del virus Epstein-Barr en el plasma mostró una especificidad alta, pero una sensibilidad baja (todas las categorías) o alta (categorías avanzadas o neoplásicas) para identificar PTLD. Se observó el desempeño diagnóstico más alto en las siguientes condiciones: 1) al identificar una variación de carga en CMP o en plasma; 2) combinando la medición de la carga viral en CMP y en plasma. La mejor capacidad diagnóstica para identificar las etapas tempranas de los PTLD se logró mediante el seguimiento simultáneo de la carga viral en CMP y en plasma; se propone un algoritmo.

Epstein-Barr virus load in transplant patients: Early detection of post-transplant lymphoproliferative disorders.

High levels of circulating EBV load are used as a marker of post-transplant lymphoproliferative disorders (PTLD). There is no consensus regarding the threshold level indicative of an increase in peripheral EBV DNA. The aim of the study was to clinically validate a developed EBV quantification assay for early PTLD detection. Transversal study: paired peripheral blood mononuclear cells (PBMC), plasma and oropharyngeal lymphoid tissue (OLT) from children undergoing a solid organ transplant with (n=58) and without (n=47) PTLD. Retrospective follow-up: 71 paired PBMC and plasma from recipients with (n=6) and without (n=6) PTLD history. EBV load was determined by real-time PCR. The diagnostic ability to detect all PTLD (categories 1-4), advanced PTLD (categories 2-4) or neoplastic PTLD (categories 3 and 4) was estimated by analyzing the test performance at different cut-off values or with a load variation greater than 0.5log units. The higher diagnostic performance for identifying all, advanced or neoplastic PTLD, was achieved with cut-off values of 1.08; 1.60 and 2.47log EBVgEq/10(5) PBMC or 2.30; 2.60; 4.47loggEq/10(5) OLT cells, respectively. EBV DNA detection in plasma showed high specificity but low (all categories) or high (advanced/neoplastic categories) sensitivity for PTLD identification. Diagnostic performance was greater when: (1) a load variation in PBMC or plasma was identified; (2) combining the measure of EBV load in PBMC and plasma. The best diagnostic ability to identify early PTLD stages was achieved by monitoring EBV load in PBMC and plasma simultaneously; an algorithm was proposed.

Distribution of HPV-16 variants among isolates from Paraguayan women with different grades of cervical lesion.

OBJECTIVE: To determine the distribution of HPV-16 variants among Paraguayan women with different grades of cervical lesions. METHODS: Sixty-seven HPV-16-positive cervical samples obtained from women attending health centers in Paraguay between March 2007 and April 2009 were examined, including 29 low-grade squamous intraepithelial lesion (LSIL), 29 high-grade squamous intraepithelial lesion (HSIL), 4 cervical cancer, and 5 normal cytology samples. The specimens were analyzed by PCR-directed sequencing of a 364-bp fragment of the long control region of HPV-16, and a phylogenetic tree was compiled with MEGA 5.0 software. RESULTS: Most HPV-16 variants belonged to the European branch (82%); these variants were detected among 25 of 29 women with LSIL, 22 of 29 women with HSIL, 3 of 4 women with cervical cancer, and all women with normal cytology. Two isolates yielded new variants of the European branch with nucleotide substitutions at positions A7752C and A7810T. Non-European variants, such as African type 1 (1.5%) and Asian-American (16.5%), were detected only among women with cervical lesions (4/29, LSIL; 6/29, HSIL; 1/29, cervical cancer). These variants had at least 6 nucleotide substitutions adjacent to or within transcription factor binding sites. CONCLUSION: All branches of HPV-16 variants were detected among Paraguayan women with cervical lesions.

Human papilloma virus risk factors for infection and genotype distribution in aboriginal women from Northern Argentina.

The mortality rate for cervical cancer (CC) in Northern Argentina is three times higher than the average for the country (7.8 deaths/100,000 women). We determined the prevalence and genotype distribution of human papillomavirus (HPV) in 227 sexually active women of the native Pilagá community in Formosa, Argentina. We also conducted an HPV-16 variant analysis and studied several community factors that might play a role in viral entry and infection. Endo and exocervical samples were tested for HPV DNA with MY09/11-PCR or with GP5+/6+-PCR. HPV was detected in 46.7% of the samples and 21 different types were found; the most frequent being HPV-16 (19.4%), -6 and -18 (5.3%), -58 (3.5%) and -31 and -33 (3.1%). In relation to HPV-16 variants, 68.2% were European and 31.8% Asian-American. Among the cofactors analyzed only disposal of hu man excreta to the open air (P=0.01) was significantly associated with HPV infection. Our prevalence estimates clearly show that Pilagá women are highly exposed to or infected with high risk HPV types and therefore are at a high risk of developing precancerous lesions and eventually CC at the population level.

Human papillomavirus risk factors for infection and genotype distribution in aboriginal women from Northern Argentina / Virus papiloma humano (hpv) en mujeres de la etnia Pilagá del nordeste argentino: Factores de riesgo de infección y distribución de tipos virales

The mortality rate for cervical cancer (CC) in Northern Argentina is three times higher than the average for the country (7.8 deaths/100 000 women). We determined the prevalence and genotype distribution of human papillomavirus (HPV) in 227 sexually active women of the native Pilagá community in Formosa, Argentina. We also conducted an HPV-16 variant analysis and studied several community factors that might play a role in viral entry and infection. Endo- and exocervical samples were tested for HPV DNA with MY09/11-PCR or with GP5+/6+-PCR. HPV was detected in 46.7% of the samples and 21 different types were found; the most frequent being HPV-16 (19.4%), -6 and -18 (5.3%), -58 (3.5%) and -31 and -33 (3.1%). In relation to HPV-16 variants, 68.2% were European and 31.8% Asian-American. Among the cofactors analyzed only disposal of human excreta to the open air (P=0.01) was significantly associated with HPV infection. Our prevalence estimates clearly show that Pilagá women are highly exposed to or infected with high risk HPV types and therefore are at a high risk of developing precancerous lesions and eventually CC at the population level.

La tasa de mortalidad por cáncer cervical (CC) en la región norte de la Argentina es tres veces más alta que la media del país (7.8 muertes/100 000 mujeres). En el presente trabajo se determinó la prevalencia de infección por virus papiloma humano (VPH) y la distribución y frecuencia de los genotipos en 227 mujeres sexualmente activas de la etnia aborigen Pilagá (Formosa, Argentina). También se realizó un análisis de las variantes intratípicas de VPH-16 presentes en la comunidad y se analizaron diversos factores socioculturales que podrían tener algún rol destacado en la transmisión de la infección viral. Se estudiaron muestras de células endo-exocervicales mediante PCR basadas en los cebadores MY09/11 y GP5+/6+ con posterior restricción enzimática y/o hibridación dot-blot. La infección por VPH fue detectada en el 46.7% de las mujeres analizadas. Fueron identificados 21 genotipos, de los cuales los más frecuentes fueron HPV-16 (19.4%), -6 y -18 (5.3%), -58 (3.5%) y -31 y -33 (3.1%). Respecto al HPV-16, se encontraron 68.2% de variantes europeas y 31.8% de asiático-americanas. Entre los cofactores analizados, solo la disposición de excretas al aire libre estuvo significativamente asociada con la infección por VPH (P = 0.01). Los datos obtenidos reflejan que la comunidad Pilagá está altamente expuesta a las infecciones por genotipos de alto riesgo de VPH, lo cual puede estar asociado a una alta incidencia de lesiones cervicales preneoplásicas y neoplásicas.

Human papillomavirus (HPV) detection and Papanicolaou cytology in low-resource women in Posadas city, Misiones, Argentina / Detección del virus papiloma humano (HPV) y citología de Papanicolaou en mujeres de bajos recursos de la ciudad de Posadas, Misiones, Argentina

The objective of this study was to determine the prevalence of HPV infection and cervical lesions present in women who attended a health center in a low-resource area of the city of Posadas, Misiones, Argentina. Cervical cell samples (n = 163) were processed for Papanicolaou cytology and HPV-PCR tests. Socio-cultural risk factors were estimated using the odds ratio (OR, CI 95 %). Cervical lesions were detected in 14.7 % of women. The general prevalence of HPV infection was of 38 %. The most common types among the total population were HPV-16 (9.8 %) and HPV-33 (9.3 %). HPV-16 was detected in association with 29.2 % and 6.5 % of women with and without cervical lesions, respectively, the OR being 5.3 (1.8-15.8). Risk factors for HPV-16 infection were a smoking habit and a history of previous sexually-transmitted diseases. These data are important for the implementation of prevention programs, including an appropriate introduction of vaccination and the baseline for virological surveillance in the vaccine era.

El objetivo de este estudio fue determinar la prevalencia de la infección por HPV y de lesiones cervicales en mujeres asistidas en un centro de salud situado en un área de bajos recursos de la ciudad de Posadas, Misiones, Argentina. Las muestras (n = 163) fueron examinadas mediante las pruebas de Papanicolaou y de PCR para HPV. Los factores socio-culturales de riesgo fueron identifcados mediante el cálculo de la odds ratio (OR, IC 95 %). Se detectaron lesiones cervicales en el 14,7 % de las mujeres. La prevalencia de infección por HPV fue de 38 %. Los tipos más frecuentes en la población total fueron HPV-16 (9,8 %) y HPV-33 (9,3 %). El HPV-16 se detectó asociado al 29,2 % y al 6,5 % de las mujeres con lesiones del cuello uterino y sin ellas, respectivamente, con un OR de 5,3 (1,8-15,8). Los factores de riesgo para la infección por HPV-16 fueron el hábito de fumar y el antecedente de enfermedades de transmisión sexual. Estos datos son importantes para la ejecución de los programas de prevención, incluyendo una introducción adecuada de la vacunación y la línea de base para la vigilancia virológica en la era de la vacuna.

Human papillomavirus (HPV) detection and Papanicolaou cytology in low-resource women in Posadas city, Misiones, Argentina.

The objective of this study was to determine the prevalence of HPV infection and cervical lesions present in women who attended a health center in a low-resource area of the city of Posadas, Misiones, Argentina. Cervical cell samples (n = 163) were processed for Papanicolaou cytology and HPV-PCR tests. Socio-cultural risk factors were estimated using the odds ratio (OR, CI 95 %). Cervical lesions were detected in 14.7 % of women. The general prevalence of HPV infection was of 38 %. The most common types among the total population were HPV-16 (9.8 %) and HPV-33 (9.3 %). HPV-16 was detected in association with 29.2 % and 6.5 % of women with and without cervical lesions, respectively, the OR being 5.3 (1.8-15.8). Risk factors for HPV-16 infection were a smoking habit and a history of previous sexually-transmitted diseases. These data are important for the implementation of prevention programs, including an appropriate introduction of vaccination and the baseline for virological surveillance in the vaccine era.