Interleukin-1 synergy with phosphoinositide pathway agonists for induction of interleukin-2 gene expression: molecular basis of costimulation.

The macrophage-derived cytokine interleukin-1 (IL-1) can provide a second signal with antigen to elicit production of interleukin-2 (IL-2) by helper T cells. The pathway(s) involved remains controversial, with protein kinase C and cyclic AMP (cAMP) invoked as possible second messengers. In the murine thymoma EL4.

Regulatory anatomy of the murine interleukin-2 gene.

We have cloned the mouse IL2 gene and sequenced 2800 bp of 5' flanking DNA. Comparison to the previously reported human sequence revealed extensive identity (approximately 86%) between the two genes from +1 to -580 with additional small islands of homology further upstream. Proximal sites which have been shown to be important in regulation of the human IL2 gene are well conserved in sequence and location.

Residual Scaling: An Alternative to Correspondence Analysis for the Graphical Representation of Residuals from Log-Linear Models.

The method of correspondence analysis, applied to a contingency table, provides a graphical representation of departures from the independence model. Generalized correspondence analysis has been proposed as a way of graphically representing departures from models other than independence. However, generalized correspondence analysis does not necessarily decompose a chi-square statistic for departures from non-independence models.

Two mechanisms by which fluorescent oxonols indicate membrane potential in human red blood cells.

Optical potentiometric indicators have been used to monitor the transmembrane electrical potential (Em) of many cells and organelles. A better understanding of the mechanisms of dye response is needed for the design of dyes with improved responses and for unambiguous interpretation of experimental results. This paper describes the responses to delta Em of 20 impermeant oxonols in human red blood cells.

Calcium, cell shrinkage, and prolytic state of human red blood cells.

The effects of intracellular calcium, or Cac, on the Na permeability of human red blood cells were examined during 3-h incubations with the Ca ionophore A23187 and varied external Ca, Cao. Above 3 microM Cao, Nac increased significantly as ATP decreased. Maintenance of normal ATP with vanadate did not prevent the gain of Nac.

Differential transient and long-term expression of DNA sequences introduced into T-lymphocyte lines.

We have used a protoplast fusion protocol to introduce the genes encoding neomycin phosphotransferase (neo) and chloramphenicol acetyltransferase (CAT) into murine and human T-lymphocyte lines. Plasmid constructs containing the neo gene under the control of the promoters from the Rous sarcoma virus long terminal repeat (RSV LTR), the SV40 early region, or the herpes simplex virus thymidine kinase gene (HSV TK) can stably transform each of three T-cell lines to G-418 resistance. The characteristic frequencies for different cell lines can differ by at least two orders of magnitude, although initial DNA uptake and transient expression are similar.

Inducible expression of a cloned heat shock fusion gene in sea urchin embryos.

A fusion gene construct, in which the coding sequence for bacterial chloramphenicol acetyltransferase (CAT; acetyl-CoA: chloramphenicol 3-O-acetyltransferase, EC 2.3.1.