ABSTRACT
Immunisation by intraperitoneal injection of an oil-emulgated recombinant partial capsid protein (rT2) from striped jack nervous necrosis virus (SJNNV) was performed on adult turbot Scophthalmus maximus and Atlantic halibut Hippoglossus hippoglossus. A specific humoral immune response was recorded in both species, and the levels of rT2-specific antibodies increased markedly in all groups during the 20 wk experiment. A challenge model for SJNNV was established by intramuscular injection of juvenile turbot. The turbot developed viral encephalopathy and retinopathy (VER), also known as viral nervous necrosis (VNN), with cumulative mortality in the range of 25 to 66%, after intramuscular inoculation with SJNNV propagated in the striped snake head cell line (SSN-1). Although neither clinical signs nor mortality were registered, SJNNV was neuroinvasive after bath exposure. The infection after both modes of challenge was verified by means of immunohistochemistry and RT-PCR, and SJNNV was reisolated in cell culture. The results indicate that SJNNV may have entered the central nervous system (CNS) by axonal transport through motor nerves after intramuscular inoculation. A vaccine efficacy test was performed on juvenile turbot, employing oil emulsified rT2 as a test vaccine and intramuscular inoculation of SJNNV. Significant protection was observed when the challenge was performed 10 wk post-vaccination.
Subject(s)
Capsid/immunology , Fish Diseases/immunology , Flatfishes/virology , RNA Virus Infections/veterinary , RNA Viruses/immunology , Viral Vaccines , Animals , Antibodies, Viral/analysis , Electrophoresis, Polyacrylamide Gel/veterinary , Fish Diseases/prevention & control , Fish Diseases/virology , Flatfishes/immunology , Immunohistochemistry/veterinary , Injections, Intramuscular/veterinary , Injections, Intraperitoneal/veterinary , RNA Virus Infections/immunology , RNA Virus Infections/prevention & control , RNA, Viral/analysis , Recombinant Proteins/immunology , Reverse Transcriptase Polymerase Chain Reaction/veterinary , Vaccination/veterinary , Viral Vaccines/administration & dosage , Viral Vaccines/immunologyABSTRACT
Kaolin is widely used in diagnostic virology, mainly to remove serum lipoproteins that may interfere with antibody assaying. The binding kinetics of antibody to kaolin at different pH values and with varying amounts of kaolin indicated a uniform and characteristic binding pattern for IgG with maximum adsorption at pH 5 and no adsorption at pH above 9. To avoid loss of IgG antibody adsorption with kaolin should therefore be performed at pH greater than or equal to 9. The amount adsorbed increased with the amount of kaolin used. The IgM pattern was less uniform with maximum adsorption of total IgM at about 7.0, the amount adsorbed being highly dependent on kaolin concentration. Serum lipoproteins were rapidly and strongly adsorbed independent of pH from 7 to 11 and independent of the lipoprotein content of the serum. The amount of kaolin used was, however, critical.
Subject(s)
Antibodies/metabolism , Kaolin/metabolism , Adsorption , Hemagglutinins, Viral/antagonists & inhibitors , Humans , Hydrogen-Ion Concentration , Immunoglobulin G/metabolism , Immunoglobulin M/metabolism , Immunoglobulins/metabolism , In Vitro Techniques , Kinetics , Lipoproteins/blood , Lipoproteins/metabolism , Protein BindingABSTRACT
Kaolin strongly adsorbed rheumatoid factor (RF) and mono-nucleosis antibodies, while cold agglutinins and some antimicrobial IgM antibodies were poorly adsorbed. Maximum adsorption took place at a pH of about 7. The degree of adsorption also depended on the amount of kaolin. Rheumatoid factor could be eluted from kaolin at pH 11 after adsorption at pH 7. The reported heterogeneity with regard to reactivity with kaolin is suggested to be due to hydrophobic interactions.
