Metastatic MHC class I-negative mouse cells derived by transformation with human papillomavirus type 16

In the endeavour to develop a model for studying gene therapy of cancers associated with human papillomaviruses (HPVs), mouse cells were transformed with the HPV type 16 (HPV16) and activated H-ras oncogenes. This was done by contransfection of plasmid p16HHMo, carrying the HPV16 E6/E7 oncogenes, and plasmid pEJ6.6, carrying the gene coding for human H-ras oncoprotein activated by G12V mutation, into secondary C57BL/6 mouse kidney cells. An oncogenic cell line, designated MK16/1/IIIABC, was derived. The epithelial origin of the cells was confirmed by their expression of cytokeratins. No MHC class I and class II molecules were detected on the surface of MK16/1/IIIABC cells. Spontaneous metastases were observed in lymphatic nodes and lungs after prolonged growth of MK16/1/IIIABC-induced subcutaneous tumours. Lethally irradiated MK16/1/IIIABC cells induced protection against challenge with 105homologous cells, but not against a higher cell dose (5 × 105). Plasmids p16HHMo and pEJ6.6 were also used for preventive immunization of mice. In comparison with a control group injected with pBR322, they exhibited moderate protection, in terms of prolonged survival, against MK16/1/IIIABC challenge (P< 0.03). These data suggest that MK16/1/IIIABC cells may serve as a model for studying immune reactions against HPV16-associated human tumours. © 2001 Cancer Research Campaign http://www.bjcancer.co

Proteome changes in platelets activated by arachidonic acid, collagen, and thrombin

<p>Abstract</p> <p>Background</p> <p>Platelets are small anucleated blood particles that play a key role in the control of bleeding. Platelets need to be activated to perform their functions and participate in hemostasis. The process of activation is accompanied by vast protein reorganization and posttranslational modifications. The goal of this study was to identify changes in proteins in platelets activated by different agonists. Platelets were activated by three different agonists - arachidonic acid, collagen, and thrombin. 2D SDS-PAGE (pI 4-7) was used to separate platelet proteins. Proteomes of activated and resting platelets were compared with each other by Progenesis SameSpots statistical software; and proteins were identified by nanoLC-MS/MS.</p> <p>Results</p> <p>190 spots were found to be significantly different. Of these, 180 spots were successfully identified and correspond to 144 different proteins. Five proteins were found that had not previously been identified in platelets: protein CDV3 homolog, protein ETHE1, protein LZIC, FGFR1 oncogene partner 2, and guanine nucleotide-binding protein subunit beta-5. Using spot expression profile analysis, we found two proteins (WD repeat-containing protein 1 and mitochondrial glycerol-3-phosphate dehydrogenase) that may be part of thrombin specific activation or signal transduction pathway(s).</p> <p>Conclusions</p> <p>Our results, characterizing the differences within proteins in both activated (by various agonists) and resting platelets, can thus contribute to the basic knowledge of platelets and to the understanding of the function and development of new antiplatelet drugs.</p

The genome sequence of E. coli W (ATCC 9637): comparative genome analysis and an improved genome-scale reconstruction of E. coli

Background: Escherichia coli is a model prokaryote, an important pathogen, and a key organism for industrial biotechnology. E. coli W (ATCC 9637), one of four strains designated as safe for laboratory purposes, has not been sequenced. E. coli W is a fast-growing strain and is the only safe strain that can utilize sucrose as a carbon source. Lifecycle analysis has demonstrated that sucrose from sugarcane is a preferred carbon source for industrial bioprocesses

The effect of the size and shape of chestnuts on the identification of horses

A study was carried out on 11 horse breeds comprising of the Akhal Teke (n = 23); English Thoroughbred (n = 23); Arabian Thoroughbred (n = 18); Czech Warm-Blood (n = 21); Old Kladrubian horse (n = 20); Hucul horse (n = 20); Czech – Moravian Belgian horse (n = 20); Noriker horse (n = 7); Silesian Noriker (n = 14); Haflinger (n = 20); Shetland pony (n = 20) to determine the shape and size of chestnuts. Chestnuts of 206 horses classified in three phylogeny classes were measured and drawn. The necessary data (breed; sex; name; sire; dam; sire of dam; age of horse; colour of horse; colour of the chestnut; bone) were entered into a special form. In the form the outlines of the shapes of the chestnuts were drawn; using a calliper we measured the protrusion of the chestnut at its highest point and the width at the widest part of the chestnut. We found no identical or similar shapes of the chestnuts within the breed or phylogeny class. We confirmed that the outlines of the chestnuts can be used as identifying marks because they are unique for each horse. We also tried to determine how the size of the chestnut is related to the strength of the skeleton but we failed to prove this dependence statistically. Using the general linear model (GLM) we discovered a statistically highly significant effect of the phylogeny class on the height and width of the chestnuts on all four limbs. The age factor has a statistically highly significant effect on the width of the chestnut on both front legs. Sex has a statistically significant effect on the height of the chestnut on both hind legs