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Human papillomavirus (HPV) DNA is preferentially found in spontaneous abortions, specifically residing in trophoblasts, and transfected HPV-16 DNA replicates and produces progeny in 3A trophoblasts in culture. In this study 3A trophoblasts were shown to display both HPV receptors and infection by HPV-31b and HPV-6 virus resulted in de novo (increasing) HPV DNA replication in these cells (inhibited by neutralizing anti-HPV31b antibodies). Reverse transcription-polymerase chain reaction analysis revealed that E1;E4, E6, and L1 were significantly expressed at days 5 (early) and 10 (late), respectively, and in situ immunocytochemistry verified L1 protein expression. Perhaps most important, HPV 31b virus infection caused both a decrease in 3A trophoblast cell numbers in a dose-dependent manner and a low trophoblast-endometrial cell adhesion (both inhibited by neutralizing anti-HPV-31 antibodies). These data further support the hypothesis that HPVs are fully active in trophoblasts and may cause some spontaneous abortions.

The risk of cervical cancer, one of the most prevalent cancers in the world, is determined by two viruses. Human papillomavirus (HPV) is the main risk factor for developing cervical cancer. However, although little known, it is well substantiated that the human Parvovirus adeno-associated virus type 2 (AAV), and its encoded Rep78 protein, interacts with HPV and lowers the risk of cervical cancer. HPV also contributes to AAV inhibition by serving as a helper virus for AAV and stimulating higher AAV replication levels. Here we surveyed four HPV-16 early genes, E1, E2, E6 and E7, for their ability to increase/decrease the basal level of AAV replication in stratifying squamous epithelium (the epithelial raft culture system). It was found that the HPV-16 E1, E2 and E6 genes were able to help/enhance AAV-2 replication in epithelial raft cultures. Under these conditions, with all the HPV genes being expressed from the AAV p5 promoter, E1 appeared to have the strongest enhancing effect on AAV DNA replication (Southern blot), RNA expression (RT-PCR), protein expression (Western blot) and AAV virion production (2 plate-Southern blot). Further study of E1 mutants showed that the carboxy-half of E1, the putative helicase/ATPase domain, was the main contributor of helper activity. These data are important for understanding the HPV-AAV interaction and its effect on modifying cervical cancer risk. These data also suggest the possibility that the identified HPV helper genes may be useful in the generation of recombinant (r)AAV virions for gene therapy, as rAAV is increasing in popularity for such purposes.

With 2 plates in the text) Skin of the Indian tree frog, Polyprdutes maculatus (Rhacophoridae), was studied in the context of self-wiping behaviour which functions to expel and distribute cutaneous secretions recently shown to retard evaporative water loss. The secretions contain both mucus and lipids and are derived from a common gland considered to be homologous with characteristic anuran mucous glands. The glands are bipotcnt and secrete both mucus and lipoid products which are evidently mixed within the glandular lumen. Another type of gland resembling characteristic anuriin serous (or granular) glands is found in dorsal but not ventral skin, whereas the lipid-secreting mucous glands are found in skin associated with all body surfaces. There is no distinct, lipid-secreting gland present in the skin of this species other than the mucous glands. These histochemical data complement the earlier finding that resistance to evaporative water loss in this species is relatively small compared with phyllomedusine .watetproof frogs which also exhibit wiping behaviour associated with secretion of lipids. Thus, wiping behaviour may have evolved in association with mucous secretions before dominant lipoid secretions resulted from strong selection for water conservation.