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B L Hall

Publications and source records attributed to B L Hall.

28 records · Page 2Linked to original sources
PubMed1992

PCR-based analysis of the T-cell receptor V beta multigene family: experimental parameters affecting its validity.

The validity of semiquantitative, PCR-based analysis of gene expression within a multigene family, the human T-cell receptor (TCR) beta chain variable region family, was investigated. Primer comparability was addressed by grouping hybridization temperatures and limiting the size range of amplified fragments. Primers selected satisfied criteria for comprehensiveness, match to targets and discrimination of nontargets. Specificity was enhanced by maximizing mismatches with nontargets and using an elevated hybridization temperature. Reaction conditions are described that ensure specificity while maintaining sensitivity. Several results confirmed primer specificity. Limits on precision were documented: probable error was 3%-7% of mean value for target prevalences (% of all TCR mRNA represented by a particular V beta) in the 5%-40% range. Accuracy was limited by the nonlinear relationship between target prevalence and signal obtained. Because of this relationship, the effect of the observed limits of precision varied. Valid distinctions were possible between sufficiently separated prevalences, i.e., 0%-1%, 3%-5%, 10%, 30%, greater than 50%. Additional concerns addressed include: standardization of signals, coamplifiation and effects of primer artifacts, and the nature of the mRNA pool. Only when theoretical and practical limits in precision and accuracy are acknowledged can semiquantitative, PCR-based analysis be used with confidence to assess gene usage within a large, multigene family.

Base Sequence↗
PubMed1990

T-cell receptor gene usage and expression in renal allograft-derived T-cell lines.

Southern blot analyses indicate that the T-cell receptors of alloreactive T-cell lines derived from needle biopsies of human kidney allografts are selected based on beta-chain usage. In order to examine this selection at the level of T-cell-receptor expression, we have generated monoclonal antibodies directed toward the T-cell-receptors of three allograft-derived T-cell lines, MH3, WP3, and EH3. Monoclonal antibodies have been isolated which appear to react specifically with each of these three T-cell lines. One anti-MH3 antibody precipitates a molecule from the surface of MH3 cells that comigrates with the alpha/beta TcR on a polyacrylamide gel. Ten WP3-reactive monoclonal antibodies were identified which cause a modulation of CD3 from the surface of WP3 T cells, although none as yet precipitates a molecule from lysates of surface 125I-labeled WP3 cells. Since Northern blot analysis of EH3 RNA has revealed that a member of the V beta 6 gene family is expressed by this T-cell line, we are attempting to identify a monoclonal antibody reactive with this V beta 6 gene product.

Antibodies, Monoclonal↗
PubMed1989

Increased expression of glycolysis-associated genes in oncogene-transformed and growth-accelerated states.

An accelerated rate of glucose transport and catabolism is a common characteristic of cellular transformation. We have previously found elevated expression of the glycolytic enzyme glyceraldehyde-3-phosphate dehydrogenase (GAPDH) in human pancreatic and colonic adenocarcinomas (Schek et al.: Cancer Res 48:6354-6359, 1988). To investigate further the expression of this enzyme in the process of tumorigenesis, we examined GAPDH expression in a panel of oncogene-transformed fibroblasts. Significant elevations of GAPDH mRNA and glucose transporter protein mRNA levels were observed in ras- and mos-transformed NIH 3T3 cells, whereas little or no change was found in c-src-, v-src-, c-myc-, E1A-, v-fos-, and PKC-gamma-transfected cells. Furthermore, the level of GAPDH mRNA correlated with the transformed state in a series of ras-transformed and revertant cell lines. Immunoblot analysis confirmed that GAPDH polypeptide was significantly elevated in the cell lines with elevated mRNA levels. Cell cycle analysis data suggested that the effect on GAPDH expression correlated with oncogene expression rather than cell growth fraction. These results suggest that altered GAPDH gene expression occurs during some growth deregulated states, and this, along with increased glucose transporter (and possibly other glycolytic enzyme) expression, is likely to contribute to the increased metabolic capacity of cells in these states.

Animals↗
PubMed1989

The hospitalized elderly and intergenerational conflict.

In a study investigating intergenerational conflict between adult children and their hospitalized, chronically ill elderly parents, data on present and future conflict, areas of conflict, and presence of negative feelings were collected from both generations. Adult children and their parents report the presence of both types of conflict as well as negative feelings. However, some marked differences of perception between the generations for the variables under study were found. The older generation cite much less conflict. These findings as well as implications for practice are discussed.

Adult↗
PubMed1988

Increased glyceraldehyde-3-phosphate dehydrogenase gene expression in human pancreatic adenocarcinoma.

To identify and characterize genes, the products of which play a role in pancreatic adenocarcinoma, we constructed a complementary DNA (cDNA) library using mRNA from the pancreatic adenocarcinoma cell line HPAF, grown as a nude mouse tumor. Through differential screening, we identified a cDNA clone, pII5B, that is homologous to an mRNA expressed at significantly higher levels in HPAF cells than in normal human pancreas. The pII5B cDNA was homologous to the 3'-untranslated region of glyceraldehyde-3-phosphate dehydrogenase (GAPDH, EC 1.2.1.12)mRNA. Partial sequencing of several HPAF tumor GAPDH cDNA clones revealed no significant differences from previously published GAPDH cDNA sequences. Increased levels of GAPDH mRNA, relative to actin mRNA levels, were found in six pancreatic adenocarcinoma cell lines and two nude mouse tumors, when compared to normal pancreas. Enolase and glucose transporter mRNA levels were also increased in HPAF cells and nude mouse tumor, suggesting a general increase in expression of genes associated with glycolysis in pancreatic adenocarcinoma. Levels of GAPDH protein were elevated in nude mouse tumors and fresh human pancreatic adenocarcinomas compared to normal pancreas. High GAPDH levels may be characteristic of human adenocarcinomas, since colon adenocarcinomas also exhibited high levels of GAPDH compared to normal colon.

Adenocarcinoma↗