Detección del virus de papiloma humano en pacientes / Detection of human papilloma virus in patients with scamous intraephitelial lesions of uterine cervix

Detectar y tipificar los virus de papiloma humano, en pacientes con lesiones intraepiteliales escamosas de cuello uterino mediante reacción en cadena de la polimerasa. A 100 pacientes se les tomó muestra para reacción en cadena de la polimerasa, y se les practicó citología, colposcopia, y biopsia cervical. Criterios de exclusión: pacientes con leucorrea, sangrado genital e infección por virus de papiloma humano, tratadas por vía local o sistémica. Consulta de Ginecología del Hospital Universitario "Antonio P. de Alcalá", Cumana, Estado Sucre. 98 por ciento de las muestras presentaron genoma viral para reacción en cadena de la polimerasa y 2 por ciento fueron negativos. El 52,38 por ciento de los casos NIC I presentó virus de papiloma humano tipo 16, 23, 81 por ciento tipo 18, 23,81 por ciento tipo 31. De las pacientes con NCI II; 23,81 por ciento asociadas a virus de papailoma humano tipo 11 y 76,19 por ciento tipo 31. Un 37,5 por ciento de los casos con NCI III fueron portadores del virus de papiloma humano tipo 31. A las pacientes con cancirnoma invasor se les detectó virus de papiloma humano tipo 16, de alto riesgo oncogénico. En 99,98 por ciento de las pacientes se observó el punteado como hallazgo colposcópico anormal más frecuente. Comparando los estudios de hibridación molecular con especificidad de 100 por ciento. La biopsia cervical, una sensibilidad de 62 por ciento y una especificidad de 100 por ciento. La reacción en cadena de polimerasa constituye una metodología de alta sensibilidad para el diagnóstico de infección por virus de papiloma humano, permitiendo identificar lesiones adecuadas para el tratamiento conservados y la detección de precursores del cáncer, conduciendo así a una terapia más sensible y eficaz de la patología cervicouterina

Improved immunodetection of human papillomavirus E7

Human papillomavirus E7 (HPV E7) is a viral oncoprotein that plays an important role in cervical carcinogenesis through binding with retinoblastoma protein (Rb). Inactivation of Rb by E7 is necessary but not sufficient for cellular transformation, suggesting other protein-protein interactions are required for E7-mediated cellular transformation aside from the interaction with Rb. However, studies on the oncogenic function of HPV E7 have been limited by its poor immunoreactivity. In this report, we show that the fixation of purified recombinant HPV E7 on blotted nitrocellulose membrane with glutaldehyde markedly enhanced the immunoreactivity of HPV E7 protein. Using HeLa and Caski cell line which are infected with HPV 18 and HPV 16, respectively, we demonstrated that native HPV E7 proteins also could be detected by this method. These results therefore can provide the experimental conditions for detection of HPV E7 proteins with greater sensitivity and may help to analyze E7 functions.

Expression and localization of human papillomavirus type 16 E6 and E7 open reading frame proteins in human epidermal keratinocyte

Over 60 different types of human papillomavirus (HPV) have been identified, and they are classified into high and low risk groups based on the risk for malignant progression of HPV associated lesions. HPVs belonging to a high risk group have been shown to express two major transforming proteins, E6 and E7. With respect to the transforming activity of these proteins, many investigators have reported the location of these proteins in the cell, but their results are still controversial. In the present study, HPV type 16 E6 or E7 open reading frame (ORF) proteins were expressed and localized in human epidermal keratinocytes (RHEK-1) using the vaccinia virus as an expression vector. Immunofluorescence detection using monoclonal antibodies against E6 or E7 ORF proteins revealed that E6 or E7 proteins of HPV type 16 were located in the cytoplasm of RHEK-1 cells. These results suggest that E6 and E7 proteins bind to the tumor suppressor counterparts, thereby preventing transport of these proteins into the nucleus. These antioncogene products that fail to be rapidly transported out of the cytosol may be degraded by certain proteases such as the ubiquitin dependent system. In this way, the precise function of antioncogene products in the regulation of cell growth could be destroyed, and abnormal cell growth could occur.