The neoplastically transformed (CD30hi) Marek's disease lymphoma cell phenotype most closely resembles T-regulatory cells.

INTRODUCTION: Marek's disease (MD), a herpesvirus-induced lymphoma of chickens is a unique natural model of CD30-overexpressing (CD30hi) lymphoma. We have previously proposed that the CD30hi neoplastically transformed CD4+ T cells in MD lymphomas have a phenotype antagonistic to cell mediated immunity. Here were test the hypothesis that the CD30hi neoplastically transformed MD lymphoma cells have a phenotype more closely resembling T-helper (Th)-2 or regulatory T (T-reg) cells. MATERIALS AND METHODS: We separated ex vivo-derived CD30hi, from the CD30lo/- (non-transformed), MD lymphoma cells and then quantified the relative amounts of mRNA and proteins for cytokines and other genes that define CD4+ Th-1, Th-2 or T-reg phenotypes. RESULTS AND DISCUSSION: Gene Ontology-based modeling of our data shows that the CD30hi MD lymphoma cells having a phenotype more similar to T-reg. Sequences that could be bound by the MD virus putative oncoprotein Meq in each of these genes' promoters suggests that the MD herpesvirus may play a direct role in maintaining this T-reg-like phenotype.

Bovine germinal vesicle oocyte and cumulus cell proteomics.

Germinal vesicle (GV) breakdown is fundamental for maturation of fully grown, developmentally competent, mammalian oocytes. Bidirectional communication between oocytes and surrounding cumulus cells (CC) is essential for maturation of a competent oocyte. However, neither the factors involved in this communication nor the mechanisms of their actions are well defined. Here, we define the proteomes of GV oocytes and their surrounding CC, including membrane proteins, using proteomics in a bovine model. We found that 4395 proteins were expressed in the CC and 1092 proteins were expressed in oocytes. Further, 858 proteins were common to both the CC and the oocytes. This first comprehensive proteome analysis of bovine oocytes and CC not only provides a foundation for signaling and cell physiology at the GV stage of oocyte development, but are also valuable for comparative studies of other stages of oocyte development at the molecular level. Furthermore, some of these proteins may represent molecular biomarkers for developmental potential of oocytes.

Protein expression of pectoralis major muscle in chickens in response to dietary methionine status.

The present study evaluated the effect of dietary methionine on breast-meat accretion and protein expression in skeletal muscle of broiler chickens in vivo. All broilers received a common pre-test diet up to 21 d of age, and were subsequently fed either a methionine-deficient (MD) or -adequate (MA) diet (3.1 v. 4.5 g/kg diet) from age 21 to 42 d. Dietary cystine levels were 3.7 v. 3.6 g/kg diet for the MD and MA diet, respectively. Detrimental effects on carcass yield (P=0.004), abdominal fat percentage (P=0.001), and breast-meat weight (P=0.001), yield (P=0.001), and uniformity (P=0.002) were observed and validated in birds fed MD diets. Via tandem MS, a total of 190 individual proteins were identified from pectoralis major (PM) muscle tissue. From the former composite, peptides from three proteins were observed to be present exclusively in breast muscle from those chickens fed the MD diet (pyruvate kinase, myosin alkali light chain-1, ribosomal-protein-L-29). No proteins were observed to be uniquely expressed in chickens fed MA diets. Research is warranted to further explore the possibility of the proteins pyruate kinase, myosin alkali light chain-1, or ribosomal protein L-29, as potential biological indicators of differences in protein expression of PM of chickens in response to a dietary methionine deficiency.