Cross-infection studies of normal calves infected with homologous pairs of non-cytopathic and cytopathic bovine viral diarrhoea virus (BVDV) showed significant differences in both humoral and cell-mediated immune responses against either biotype over a period of 5 months. Serological assays after primary intranasal inoculation showed striking significant (P < 0.05) differences between biotypes....

Oligodeoxynucleotides covalently linked to an acridine derivative were targeted to part of the 3'-terminal sequence which is common to the eight RNAs of type A influenza viruses. The cytopathic effect of the virus on MDCK cells in culture was strongly decreased by a heptanucleotide covalently attached to the acridine ring. Control experiments using other oligonucleotide sequences showed that th...

Induction of the cellular stress response elevates cytoplasmic levels of heat shock proteins (HSPs) belonging to multiple families. When infected with canine distemper virus or measles virus (MV), cells containing elevated HSPs support increased viral gene expression and cytopathic effect. The present work tests the hypothesis that increases in the major inducible 70 kDa HSP (hsp72) are suffici...

An explant adult foreskin cell culture (FS2-3) was compared with human lung carcinoma cell culture (A549) with regard to the ability of Haemophilus ducreyi to produce a cytopathic effect. The survival of H. ducreyi for up to 26 days in FS2-3 cells was far greater than in any previously described in-vitro culture system. H. ducreyi survived for up to 7 days in A549 cells. The H. ducreyi cells gr...

A cell system was developed for the reproducible detection of human T-lymphotropic retroviruses (HTLV family) from patients with the acquired immunodeficiency syndrome (AIDS) or with signs or symptoms that frequently precede AIDS (pre-AIDS). The cells are specific clones from a permissive human neoplastic T-cell line. Some of the clones permanently grow and continuously produce large amounts of...

Serum and peripheral blood lymphocytes from 10 patients with Crohn's disease and 10 healthy subjects were examined for immunological reactivity against chick embryo cell cultures displaying cytopathic effects after inoculation with 0.2 micro filtrates prepared from Crohn's disease intestinal tissues. Although the assay systems (indirect immunofluorescence, lymphocyte transformation, and cytotox...