Medicine and Health Sciences Commons^™

Occupational Exposure To Hepatitis C Virus: Early T-Cell Responses In The Absence Of Seroconversion In A Longitudinal Cohort Study., Theo Heller, Jens Martin Werner, Fareed Rahman, Eishiro Mizukoshi, Yuji Sobao, Ann Marie Gordon, Arlene Sheets, Averell H. Sherker, Ellen Kessler, Kathleen S. Bean, Steven K. Herrine, M'Lou Stevens, James Schmitt, Barbara Rehermann

Division of Gastroenterology and Hepatology Faculty Papers

BACKGROUND: T-cell responses have been described in seronegative patients who test negative for hepatitis C virus (HCV) RNA despite frequent HCV exposure. However, the cross-sectional design of those studies did not clarify whether T cells were indeed induced by low-level HCV exposure without seroconversion or whether they resulted from regular acute infection with subsequent antibody loss.

METHODS: Over a 10-year period, our longitudinal study recruited 72 healthcare workers with documented HCV exposure. We studied viremia and antibody and T-cell responses longitudinally for 6 months.

RESULTS: All healthcare workers remained negative for HCV RNA and antibodies. However, 48% developed proliferative T-cell …

Lineage-Specific T-Cell Responses To Cancer Mucosa Antigen Oppose Systemic Metastases Without Mucosal Inflammatory Disease., Adam Snook, Peng Li, Benjamin J Stafford, Elizabeth J Faul, Lan Huang, Ruth C Birbe, Alessandro Bombonati, Stephanie Schulz, Matthias Schnell, Laurence Eisenlohr, Scott Waldman

Adam E Snook

Cancer mucosa antigens are emerging as a new category of self-antigens expressed normally in immunologically privileged mucosal compartments and universally by their derivative tumors. These antigens leverage the established immunologic partitioning of systemic and mucosal compartments, limiting tolerance opposing systemic antitumor efficacy. An unresolved issue surrounding self-antigens as immunotherapeutic targets is autoimmunity following systemic immunization. In the context of cancer mucosa antigens, immune effectors to self-antigens risk amplifying mucosal inflammatory disease promoting carcinogenesis. Here, we examined the relationship between immunotherapy for systemic colon cancer metastases targeting the intestinal cancer mucosa antigen guanylyl cyclase C (GCC) and its effect on inflammatory …

T-Cell Specific Avian Tdt: Characterization Of The Cdna And Recombinant Enzyme., Baoli Yang, K. Gathy, M. Coleman

Baoli Yang

A cDNA clone coding for avian terminal deoxynucleotidyl transferase (TdT) has been isolated and sequenced. The size of this cDNA was 2545 bp with an open reading frame of 1521 bp and a predicted translation product of 58 kDa. Comparison of this TdT sequence with other known TdT sequences has revealed a very high degree of homology at both the DNA and predicted amino acid levels. The chicken TdT cDNA was expressed in a bacterial system and the protein was purified by affinity chromatography. The purified recombinant enzyme, with a specific activity of approximately 1700 U/mg protein, was significantly less …

Fetal Hemorrhage And Platelet Dysfunction In Slp-76-Deficient Mice., J. Clements, J. Lee, B. Gross, Baoli Yang, J. Olson, A. Sandra, S. Watson, S. Lentz, G. Koretzky

Baoli Yang

The adapter protein SLP-76 is expressed in T lymphocytes and hematopoietic cells of the myeloid lineage, and is known to be a substrate of the protein tyrosine kinases that are activated after ligation of the T-cell antigen receptor. Transient overexpression of SLP-76 in a T-cell line potentiates transcriptional activation after T-cell receptor ligation, while loss of SLP-76 expression abrogates several T-cell receptor-dependent signaling pathways. Mutant mice that lack SLP-76 manifest a severe block at an early stage of thymocyte development, implicating SLP-76 in signaling events that promote thymocyte maturation. While it is clear that SLP-76 plays a key role in …

The Ubiquitin Ligase Adaptor Ndfip1 Regulates T Cell-Mediated Gastrointestinal Inflammation And Inflammatory Bowel Disease Susceptibility., H. Ramon, C. Riling, J. Bradfield, Baoli Yang, H. Hakonarson, P. Oliver

Baoli Yang

Nedd4 family interacting protein 1 (Ndfip1) is an adaptor protein that regulates Itch, an E3 ubiquitin ligase that ubiquitylates JunB, thereby preventing interleukin (IL)-4 and IL-5 production. Mice lacking Ndfip1 or Itch develop T helper type 2 (T(H)2)-mediated inflammation in the skin and lungs and die prematurely. In this study we show that Ndfip1-/- mice also develop inflammation in the gastrointestinal tract. Inflammation is characterized by infiltration of eosinophils and T cells and is accompanied by a failure to gain weight. T cells are both necessary and sufficient for eosinophil recruitment and inflammation. This is because Ndfip1-/- T cells become …

Requirement For The Leukocyte-Specific Adapter Protein Slp-76 For Normal T Cell Development., J. Clements, Baoli Yang, S. Ross-Barta, S. Eliason, R. Hrstka, R. Williamson, G. Koretzky

Baoli Yang

The leukocyte-specific adapter molecule SLP-76 (Src homology 2 domain-containing leukocyte protein of 76 kilodaltons) is rapidly phosphorylated on tyrosine residues after receptor ligation in several hematopoietically derived cell types. Mice made deficient for SLP-76 expression contained no peripheral T cells as a result of an early block in thymopoiesis. Macrophage and natural killer cell compartments were intact in SLP-76-deficient mice, despite SLP-76 expression in these lineages in wild-type mice. Thus, the SLP-76 adapter protein is required for normal thymocyte development and plays a crucial role in translating signals mediated by pre-T cell receptors into distal biochemical events.