Molecular evaluation of the prevalence of oncogenic human papillomavirus genotypes in cervical acetowhite lesions

Effects of acetic acid on light scattering from cells

Acetic acid has been used for decades as an aid for the detection of precancerous cervical lesions, and the use of acetic acid is being investigated in several other tissues. Nonetheless, the mechanism of acetowhitening is unclear. This work tests some of the hypotheses in the literature and measures changes in light scattering specific to the nucleus and the cytoplasm. Wide angle side scattering from both the nucleus and the cytoplasm increases with acetic application to tumorigenic cells, with the increase in nuclear scattering being greater. In one cell line, the changes in nuclear scattering are likely due to an increase in number or scattering efficiency of scattering centers smaller than the wavelength of excitation light. There are likely several cellular changes that cause acetowhitening and the cellular changes may differ with cell type. These results should lead to a better understanding of acetowhitening and potentially the development of adjunct techniques to improve the utility of acetic acid application. For the well-studied case of cervical tissue, acetowhitening has been shown to be sensitive, but not specific for oncogenic changes needing treatment.

Mucosal IgG and IgA responses to human papillomavirus type 16 capsid proteins in HPV16-infected women without visible pathology

Human papillomavirus type 16 (HPV16) may infect the cervical epithelium without producing pathological changes for a long time. To investigate if mucosal antibodies are induced in HPV16-infected women without visible pathology, cervical mucus from HPV16-infected patients with and without evident pathology, along with mucus from uninfected women were analyzed for the presence of mucosal IgG and secretory IgA (sIgA) antibodies to HPV16 capsid proteins by ELISA. sIgA and IgG antibodies were found in a significantly higher proportion of infected patients compared with uninfected women (p < 0.0001). sIgA antibodies were present in 13.1% of infected patients without visible pathology, the proportion of positivity increased to 27.0% in patients with visible pathology (p = 0.001). Mucosal IgG response was observed in 6.5% of patients without and 27.5% of patients with visible pathology (p = 0.00005). The antibody mean signal strength was significantly higher in patients with than in patients without pathological evidence (p < 0.005). In conclusion, both sIgA and IgG are found in patients without pathological signs of infection, however, the response increases significantly in patients with pathological evidence, suggesting that the appearance of these changes might be associated with a more vigorous antibody-mediated mucosal reaction.