Use of cervical Cytobrush samples for dot-blot detection and Southern blot typing of human papillomaviruses using subgenomic probes.

The use of Cytobrush samples for the detection and typing of cervical human papillomavirus (HPV) infections was analyzed. The average yield of squamous cells from Cytobrush samples was on the order of 10(6) cells when the sample was collected in a lytic collection buffer, which was approximately double the content of (1) samples collected in ethanol and (2) an average biopsy specimen. The material obtained could be used for sensitive detection and typing of HPV infections using, respectively, a nonradioactive dot-blot method and the Southern blot procedure performed with subgenomic probes, which permitted a simple interpretation even in cases of mixed infections. A sample containing at least 500,000 viral copies was required for the detection and typing. At this level of sensitivity, the frequencies of HPV obtained in different risk groups varied from 6% (in "healthy" young women) to 53% (in women with abnormal cytologic findings in simultaneous smears). The noninvasive nature of the sampling procedure and the relative simplicity of the test should allow this method to be applied in large-scale studies.