Chicken antibodies to a recombinant fragment of the equine immunoglobulin epsilon heavy-chain recognising native horse IgE.

An equine immunoglobulin E (IgE) heavy-chain cDNA fragment (CH3-CH4, nucleotides 1132 to 1592) was cloned, expressed in Escherichia coli as a fusion protein with a [His]6-tag and purified over a Ni-NTA column. The recombinant protein was used to immunise hens. Testing of the raised egg yolk immunoglobulin G (IgG) in Western-blot and ELISA revealed high titres against the recombinant equine IgE fragment (reqIgEf).

Differential regulation of inducible nitric oxide synthase production in bovine and caprine macrophages.

Inducible nitric oxide synthase (iNOS) regulation in human and murine macrophages in vitro differs considerably. In this study, expression of macrophage iNOS in ruminants was addressed. Nitric oxide (NO) output by cattle and goat macrophages was as different as that by human and mouse macrophages.

The caprine arthritis encephalitis virus tat gene is dispensable for efficient viral replication in vitro and in vivo.

Caprine arthritis encephalitis virus (CAEV) is a lentivirus closely related to visna virus and more distantly to other lentiviruses, such as human immunodeficiency virus. The genomes of visna virus and CAEV contain a tat gene encoding a protein able to weakly transactivate its own long terminal repeat, suggesting that transactivation may be a dispensable function for viral replication. Three different tat gene mutants of an infectious molecular clone of CAEV were used to study their replication after transfection or infection of primary goat synovial membrane cells and of blood-derived mononuclear cells or macrophages.

The vif gene is essential for efficient replication of caprine arthritis encephalitis virus in goat synovial membrane cells and affects the late steps of the virus replication cycle.

Complex retrovirus genomes contain a variable number of accessory genes, among which is the vif gene. We investigated in vitro the role of the vif gene of caprine arthritis encephalitis virus (CAEV) by studying the phenotype of five vif mutants after infection of primary goat synovial membrane (GSM) cells and blood-derived monocytes/macrophages. Any deletion introduced into the vif gene resulted in slow and low viral replication and production of virions with an infectious titer lower than that of wild-type viral particles.

Absolute requirement for GTP in activation of human neutrophil NADPH oxidase in a cell-free system: role of ATP in regenerating GTP.

Guanine and/or adenine nucleotides appear to be involved in the activation of the superoxide-generating NADPH oxidase of phagocytic cells. Their precise roles, however, are unclear, as much of the evidence for their involvement comes from experiments in which nucleotides have been added to complex systems already rich in both endogenous nucleotides and enzymes capable of interconverting them. To circumvent this problem we have examined the role of nucleotides in neutrophil NADPH oxidase activation by using a cell-free system in which adenine and guanine nucleotide concentrations were carefully controlled and monitored by (i) depletion of endogenous nucleotides by extensive dialysis and charcoal treatment; (ii) reconstitution of the depleted system with reagents analyzed for purity; and (iii) measurement of nucleotide levels in cytosol preparations and in oxidase reaction mixtures by HPLC analysis.