No abstract

MUC1 mucin peptides stimulated cytotoxic T lymphocytes (CTL) from humans with adenocarcinomas. Peripheral blood mononuclear cells, tumor-draining lymph node cells, or tumor-infiltrating lymphocytes were stimulated using mono-nuclear cells from humans with adenocarcinomas of breast or ovary, respectively, using (a) a native MUC1 mucin tandem repeat peptide of 20 amino acids (MUC1-mtr1) plus recombinant human interleukin-2 (IL-2), (b) the mutated (T3N) MUC1-mtr1 plus IL-2, or (c) immobilized anti-CD3 plus IL-2, or (d) IL-2 alone. The CTL stimulated by each of these four conditions were predominately CD4+. However, the CTL stimulated by either the native MUC1-mtr1 or (T3N) MUC1-mtr1 showed 5-10 times greater cytotoxicity of a breast cancer cell line that expresses MUC1 compared to CTL stimulated by either anti-CD3 + IL-2 or IL-2 alone. Each incubation condition generated CTL with different variable beta gene families of T-cell receptors, implying an oligoclonal expansion of a limited CTL repertoire for each. Thus, peptide-stimulated T cells showed expression of cytotoxic cells, which was not induced by nonspecific (anti-CD3 or IL-2) stimulation.

Visual information overload is a threat to the interpretation of displays presenting large data sets or complex application environments. To combat this problem, researchers have begun to explore how haptic feedback can be used as another means for information transmission. In this paper, we show that people can perceive and accurately process haptically rendered ordinal data while under cognitive workload. We evaluate three haptic models for rendering ordinal data with participants who were performing a taxing visual tracking task. The evaluation demonstrates that information rendered by these models is perceptually available even when users are visually busy. This preliminary research has promising implications for haptic augmentation of visual displays for information visualization.

No abstract

Studies to determine if Toxoplasma gondii-specific human T cells lyse parasite-infected cells have yielded conflicting results. Furthermore, attempts to obtain human cytotoxic CD8 ؉ T lymphocytes have been difficult because of the lack of a reproducible system for their generation. By using paraformaldehyde-fixed, T. gondii-infected peripheral blood mononuclear cells as antigen-presenting cells, we developed a method whereby T. gondii-specific T-cell lines can be reproducibly generated. Six T. gondii-specific T-cell lines were generated from an individual chronically infected with T. gondii. Cytofluorometric analysis of these lines revealed >99% CD3 ؉ , 85 to 95% CD3 ؉ ␣␤ T-cell-receptor-positive (TCR ؉), 5 to 9% CD3 ؉ ␥␦ TCR ؉ , 50 to 70% CD4 ؉ , and 20 to 40% CD8 ؉ cells when cells were examined during the first 3 weeks of stimulation and >99% CD3 ؉ , >99% CD3 ؉ ␣␤ TCR ؉ , <1% CD3 ؉ ␥␦ TCR ؉ , 20 to 40% CD4 ؉ , and 60 to 80% CD8 ؉ cells when cells were examined between 5 and 11 weeks. Both CD4 ؉ and CD8 ؉ T cells had remarkable cytotoxic activity against T. gondiiinfected target cells (30 to 50% specific Cr release at an effector-to-target ratio of 30:1) but not against uninfected target cells (<10% at an effector-to-target ratio of 30:1). Cytotoxic activity by the whole T-cell lines was not T. gondii strain specific. Whole T-cell lines were cytotoxic for target cells infected with the C56 and ME49 strains and the RH strain (which was used to infect peripheral blood mononuclear cells). T. gondiispecific T-cell lines displayed the predominant expression of V␤7 TCR. The CDR3 regions of the V␤7 TCRs of these T-cell lines showed a striking degree of sequence identity (oligoclonality). T-cell lines obtained by the method reported here can be used to characterize functional activity of T-lymphocyte subsets in humans infected with T. gondii.