Pravastatin increases survival and inhibits natural killer cell enhancement factor in liver transplanted rats.

Pravastatin, a 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitor, has been shown to decrease the number of acute rejection episodes in cardiac and renal transplant patients. This study evaluates the effects of pravastatin on survival of rats following liver transplant and attempts to elucidate the mechanisms of these effects. Both survival and natural killer cell enhancing factor (NKEF) studies utilized Dark Agouti rats for donor livers transplanted into Brown Norway rats as recipients.

Recombinant natural killer enhancing factor augments natural killer cytotoxicity.

Natural killer enhancing factor (NKEF) was originally identified and studied because of its ability to enhance NK cytotoxicity in vitro. After cloning the two genes responsible for NKEF proteins, NKEF-A and -B, we found that they belong to a newly described and highly conserved antioxidant gene family. We have now produced recombinant proteins of both genes and used them to test for their ability to promote NK cytotoxicity.

Characterization of an oxidation-resistant tumor cell line and its sensitivity to immune response and chemotherapy.

Aerobic cells have several scavenger systems for protection from reactive oxygen species (ROS). We developed an ROS-resistant variant of the human erythroleukemic cell line K562 by culturing cells in glucose oxidase to produce hydrogen peroxide. Testing the activity of the scavenger systems for ROS showed these cells had a 25- to 28-fold increase in catalase activity.

Antioxidant function of recombinant human natural killer enhancing factor.

Natural killer enhancing factor (NKEF) is a member of a new class of highly conserved antioxidant proteins. Members of this family have been described as thiol-specific antioxidants. In this study, we show that recombinant proteins encoded by the two human NKEF genes (nkef-A and B) possess antioxidant function in the protection of protein and DNA from oxidative damage.