ABSTRACT
The control of tick populations by using conventional strategies poses several problems, including the appearance of organophosphate resistant strains, among others. The possibility of using alternative strategies such as vaccination with tick antigens has been suggested by several authors. One particular antigen (Bm86) has been described and shown to be able to induce a protective immunity against the cattle tick Boophilus microplus. In this paper we demonstrate by means of immunohistochemical staining that this antigen is conserved among several strains of this species. These results correlate with those showing that animals vaccinated with a preparation of recombinant Bm86 were protected against challenge with the four different strains tested, including one resistant to organophosphates. These results favour the immunization with recombinant Bm86 for the control of the cattle tick B. microplus.
Subject(s)
Cattle Diseases/prevention & control , Membrane Glycoproteins/analysis , Recombinant Proteins , Tick Infestations/veterinary , Ticks/immunology , Vaccines, Synthetic/analysis , Vaccines , Animals , Cattle , Female , Membrane Glycoproteins/immunology , Tick Infestations/prevention & control , Ticks/ultrastructure , Vaccination/veterinary , Vaccines, Synthetic/immunologyABSTRACT
Liver tissue samples from four chimpanzees submitted to viral challenge in order to test a recombinant anti-hepatitis B virus vaccine, were studied by electron microscopy. The vaccinated monkeys showed no evidences of acute viral hepatitis (AVH), demonstrating the protection against an infective viral dose; on the contrary, the non-vaccinated chimps developed signs of AVH in hepatocytes such as: different size and shape, slight dilatation of the rough endoplasmic reticulum, disappearance of the mitochondrial crests, broadening of the normal space between the membranes of the nuclear coating and presence of laminar bodies and cytoplasmic vacuoles. Furthermore, the presence of the hepatitis B virus surface (HBV) antigen was confirmed in non-vaccinated monkeys using immunocytochemical techniques. Transmission electron microscopy and immunocytochemical analysis corroborated the protective effect of the recombinant vaccine against the HBV in the vaccinated animals.
Subject(s)
Hepatitis B Vaccines/therapeutic use , Hepatitis B/pathology , Liver/pathology , Animals , Biopsy , Hepatitis B/metabolism , Hepatitis B/prevention & control , Immunohistochemistry , Liver/chemistry , Liver/ultrastructure , Pan troglodytesABSTRACT
Fine structure and function are closely related in the cells of the different tissues. For this reason a comparative study combining histochemical techniques and scanning electron microscopy can result a potentially useful tool in the search for cell markers of preneoplastic stages of the colon mucosa. With this purpose, samples of normal colon mucosa, adenomatous polyps and adenocarcinomas obtained by colonoscopy were studied by histochemical techniques for the detection of epithelial mucosubstances and by scanning electron microscopy. Differences were shown in the architectural arrangement of the colon epithelium between the normal mucosa, the adenocarcinoma and the polyps studied, while between tubular an tubulovillous adenomas no marked differential ultrastructural features were found. Acid mucosubstances distribution pattern showed that sialomucin predominated in the colon mucosa harboring a carcinoma and in the tubulo-villous polyps as well as in the mucosa remote from adenocarcinoma and from the two cases of familial polyposis coli histologically considered as tubulo-villous adenomas. On the other hand tubular adenomas and normal mucosa showed a predominance of sulfomucin.