LD Typing and the Lack of Involvement of SD Antigens in the Priming Process

Peripheral blood lymphocytes with known HLA-SD were typed for LD determinants using a panel of primed cells prepared from SD identical lymphocytes. Then these lymphocytes (with known SD and LD) were primed by x-irradiated cells from the same SD and LD group and their secondary reactions were evaluated. Disparity in SD antigens of responder and stimulator cells did not produce primed cells and lymphocytes were primed only for LD differences. This finding allows LD typing using primed cells from a panel of randomly selected lymphocytes regardless of their HLA-SD.     

Autologous adjuvant linked fibroblasts induce anti-glioma immunity: implications for development of a glioma vaccine

Summary Objectives: Adjuvant-linked vaccines have been shown to induce anti-tumor immunity in patients with a variety of solid tumors. In this study we describe anin vitro model of active immunotherapy using autologous fibroblasts as immunogen. Correlative results from glioma patients immunized with autologous fibroblasts are also described. Methods: Peripheral blood lymphocytes (PBLs) from normal subjects were immunizedin vitro against autologous skin fibroblasts coupled to the adjuvant muramyl dipeptide. The lymphocytes developed cell-mediated cytotoxicity that was measured with a short-term chromium release assay. Results ofin vitro experiments were compared to data derived from glioma patients immunized with subcutaneous injection of an autologous adjuvantlinked fibroblast vaccine. Glioma target cells and fibroblast immunogens were derived from early passage primary tissue culture. Results: A comparison of autologous vs. homologous immunogen indicated that major histocompatibility complex matching was required at the sensitization stage of immunity (17.2±3.4% specific lysis vs. 0.4±3.1%,P<0.01). Pre-treatment of fibroblast immunogen cells with interferon gamma (IFN-γ) was found to significantly increase immunity (42.2±10.0%,P<0.01), as did IFN-γ pre-treatment of tumor target cells (35.8±9.0%,P<0.01). The positive effect of IFN-γ was diminished by treatment of cells with IFN-α. Thesein vitro results correlated well within vivo data derived from glioma patients immunized with an autologous adjuvant-linked fibroblast vaccine. PBLs from patients developed direct cell-mediated cytotoxicity against autologous tumor cells. Lysis of tumor targets afterin vivo immunization increased over a three-week interval (from 1.2 ± 3.0% to 21.0 ± 3.4%,P < 0.01) while lysis of a non-MHC matched control cell line remained essentially unchanged. Conclusions: Specific lysis of glioma targetsin vitro was achieved afterin vivo sensitization with autologous adjuvant-linked fibroblasts. Collectively, the data indicate that biochemically modified autologous cells can stimulate anti-glioma immunity in humans. The degree of specific immunity seen in our patients compares favorably with other published series using glioma cells as an antigenic source. Accordingly, fibroblasts may represent a practical alternative to glioma cells for vaccine construction.     

Overexpression of cell cycle regulatory proteins correlates with advanced tumor stage in head and neck squamous cell carcinomas

Squamous cell carcinoma of the head and neck region (HNSCC) is the sixth most frequent cancer worldwide. In the USA, 30,000 new cases and 8,000 deaths are reported each year. Differences between normal epithelium and cancer cells from the upper aerodigestive tract arise from alterations in expression of specific genes controlling proliferation and immortalization. The protein products of these genes include growth factor receptors, cell cycle regulators, and tumor suppressors which affect a variety of intracellular signaling pathways. To determine how altered expression of these gene products contribute to HNSCC progression, we examined expression of epidermal growth factor receptor (EGFR), cyclins, p16INK4A, c-myc, proliferating cell nuclear antigen (PCNA), and telomerase in archival pathology specimens by immunohistochemistry. A substantial majority of HNSCC tumors showed loss of p16INK4A expression and dramatic overexpression of EGFR. Overexpression of this receptor correlated with increased cyclin A levels and high mitotic index. EGFR, cyclins A, -B1, -E, and c-myc overexpression was significantly increased in stage III and IV tumors compared to early stage cancers. hTERT was expressed in all tumors and primarily in the basal layer cells of dysplastic epithelial lesions. Suprabasal expression of hTERT was found in a significantly higher number of HNSCC cases than in dysplastic lesions. These results indicate that overexpression of cell cycle regulatory proteins correlates with advanced tumor stage in HNSCC.     

Ethics Seminars HIV Testing, Consent, and Physician Responsibilities

Emergency physicians constantly have multiple ethical obligations in the emergency department. They must understand these sometimes conflicting obligations and learn to prioritize. A case discussion is presented that exemplifies the conflict between patient privacy and society's right to know. Specific aspects of HIV testing and obtaining patient consent are presented. Teaching physicians are encouraged to use such common cases for "ethics case discussion."     

Gene interventions in the beta-adrenergic system for treating heart failure

Cardiovascular disease accounts for nearly 40% of all deaths annually in this country. Prevention management and advances in medical treatments have dramatically reduced the overall mortality rate due to heart disease. However, death due to chronic heart failure (HF) continues to rise, and effective therapy, particularly for end-stage HF, has been elusive. The myocardial beta-adrenergic receptor (betaAR) system is critical not only in chronic HF but also in acute settings where cardiac function is compromised. Adding to its importance is the fact that drugs that act by altering betaAR signal transduction are at the forefront of conventional HF therapeutic strategies. Accordingly, the ability to genetically manipulate betaAR signaling in the heart is of great interest since it may provide unique inotropic support and improve existing therapeutic strategies for HF.