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An influenza vaccine created from the M2 protein of influenza A virus fused to the hepatitis B virus core protein protected 90% to 100% of the mice that received it from a lethal virus challenge. The M2 protein is a minor part of the virus but is very stable and does not drift as other viral proteins do.

Research was conducted to examine the hypothesis that autocrine tumor necrosis factor (TNF) and lymphotoxin (LT) alpha differentially modulate cellular sensitivity to TNF/LT-alpha cytotoxicity in L929 cells. Detailed investigation of the biological activities of autocrine LT-alpha production was performed using several types of TNF-resistant L929 cell derivatives. Results indicate that the membrane retention of newly synthesized TNF or LT-alpha is critical for receptor downmodulation and TNF/LT-alpha resistance.

Research was performed to prove that the cell wall anchor of protein A from Staphylococcus aureus is functional in Lactococcus lactis. Evidence suggests that a heterologous anchor sequence can function in a highly-efficient manner to expose functional units at the surface of food-grade microorganism L. lactis. Further studies have to be undertaken as regards the biotechnological applications of this system in antigen presentation, immobilization of enzymatic groups at the surface and immobilization of production strains.

Glucocorticoids exert multiple anti-inflammatory activities, one of which is the inhibition of transcription dependent on the nuclear factor (NF)-[Kappa]B. It has been suggested that the effect of dexamethasone (DEX), a glucocorticoid analog, is attributed to an increased production of the inhibitory I[Kappa]B molecule, which in turn would bind and remove activated, DNA-bound NF-[Kappa]B complexes in the cell nucleus. Upon investigating DEX-mediated repression of interleukin-6 expression induced by tumor necrosis factor, DEX treatment was found to act directly on NF-[Kappa]B-dependent transcription, without changing the expression level of I[Kappa]B. Neither the mRNA of I[Kappa]B nor the protein was significantly elevated by a combined treatment with tumor necrosis factor and DEX of murine endothelial or fibroblast cells. The DNA-binding activity of induced NF-[Kappa]B also remained unchanged after stimulation of cells with DEX. Evidence for a direct nuclear mechanism of action was obtained by analysis of cell lines stably expressing a fusion protein between the DNA-binding domain of the yeast Gal4 protein and the transactivating p65 subunit of NF-[Kappa]B. Expression of a Gal4-dependent luciferase reporter gene activated by this nuclear fusion protein was also strongly repressed after addition of DEX. Because the DNAbinding activity of the Gal4 fusion protein was not affected by DEX, it can be concluded that the reduction of gene activation was caused by interference of the activated glucocorticoid receptor with the transactivation potential of the NF-[Kappa]B p65 subunit.

Staphylococcus aureus Cowan I cells, expressing the Photinus pyralis luciferase (luc) gene, produce light which can be used for detecting antigen-antibody complexes by immobilizing the cells on a substrate containing immunoglobulin G. The cells produce a stable glow of light for almost 30 min in the presence of luciferase. The luc gene is present downstream of the S. aureus protein A promoter and fails to affect bacterial growth or plasmid stability.

A study to characterize the pathways active in generating a selective tolerance to some of the effects of low doses of tumor necrosis factor (TNF) initiated due to its multiple injection revealed that tolerance discreetly inhibits the TNF-R75-directed pathways, specifically the part copied by interlukin-1 and RU-38486. The introduction of tolerance was found to be controlled by the excitation of TNF-R55.

Pap pili are hairlike, extracellular proteinaceous appendages of bacterial cells comprising a limited set of varied proteins. Fusion genes among Pap A and fragments coding for immunoglobin G-binding site of Staphylococcus aureus protein A were developed so that spa fragments were introduced through codon 7 or 68 encoding sequence for the full grown portion of PapA. The existence of altered operon in bacterial strain has facilitated the discovery of immunoglobulin G-binding activity at the surface of the bacterial cells.

Human tumor necrosis factor (TNF) mutants have been isolated that attach to the human TNF-R55 cell receptor but not to the TNF-R75 receptor. Binding tests involving cell lines from human larynx carcinomas showed that the mutant forms will not bind to both receptors as was the case with previous forms of TNF. The TNF mutants may become powerful tumor-fighting drugs since they cause much less systemic toxicity than earlier TNF.