Virus specific low avidity IgG (index of avidity < or =30%) were detected in patients with rubella during 7 weeks after symptoms appeared as well as in vaccinated persons which were tested 6 weeks after vaccination

Low avidity antibodies in sera were detected in 96% of patients with rubella and in 75% of vaccinated persons which were not immune before immunization. Live attenuated vaccines Ervevax, Priorix, and MMR-II had similar ability to induce low avidity IgG to rubella virus. Increase of low avidity antibodies concentration was noted after immunization of children with low levels of antibodies before vaccination. After immunization of persons with high avidity antibodies in serum, index of avidity remained above threshold. Anamnestic high avidity IgG (index of avidity 51-100%) were detected in majority of immune healthy persons (96.4%) as well as in patients with exanthematous illnesses not related to rubella infection (93.

6%). ELISA test-systems for detection of low avidity IgG to rubella virus allow to obtain reliable information about seroconversion rate and characteristics of immune response in vaccines. Detection of low avidity IgG in serum obtained 5-6 weeks after immunization points to primary immune response, whereas identification of high avidity antibodies reveals already immune persons.recipients of a plasma-derived vaccine using synthetic peptides mimicking S and hepatitis B vaccine was assessed. Each was used in turn as probes to analyse human immune responses to a licensed plasma-derived HBV vaccine. Both humoral and cellular responses were analysed with synthetic peptides representing residues 124-147 of the surface antigen of the virus (HBsAg) and residues 126-140 of the pre-S2 region. Antibody levels and affinities were assessed in radioimmunoassays with synthetic linear and cyclical forms of surface antigen peptides 124-137 and 139-147, with the gp30p25 polypeptide complex of HBsAg and with the linear pre-S2 peptide 126-140.

Levels and affinities of antibodies to the antigens increased with time during immunization. However, antibodies binding the cyclical peptide representing amino acids 139 to 147 (C139) were present at higher levels and had higher affinities than were antibodies binding the other peptides, indicating that C139 more closely approximates a domain on the native antigen than do the other peptides. No humoral responses were measured with the pre-S2 peptide. Cellular responses were assessed by in vitro stimulation of peripheral blood lymphocytes by HBsAg and by the synthetic peptides. All vaccine recipients had demonstrable lymphocyte responsiveness to HBsAg after both second and third doses of the vaccine. Of the S and pre-S peptides used, only L124 failed to induce lymphocyte stimulation in all recipients. However, there were individual variations in both the time of initial responsiveness to peptides and in the level and time of maximal stimulation.

Stimulation by native HBsAg particles, which corresponded to the appearance of anti-HBs antibody, preceded that observed using synthetic peptides. In all recipients, maximum stimulation indices with HBsAg were significantly higher than those observed with the peptides. In contrast to the absence of pre-S2 antibody, the lymphocytes from all recipients showed positive stimulation in response to the peptide representing residues 126-140 of the pre-S2 region. None of these individuals had antibodies to pre-S or an HB core peptide sequence nor did their lymphocytes respond to a synthetic peptide representing an HB core sequence.(DIVA) strategy for sero-surveillance of avian influenza virus vaccination in improvement for increased surveillance of avian influenza (AI), where vaccination is employed to control disease. We propose a novel DIVA approach for chickens using tetanus toxoid (TT) as an exogenous marker independent of serotype and relatedness of circulating and vaccine strains. Of 1779 chickens tested from without vaccination.

buy vitamin d3  adjuvanted to mineral oil was immunogenic in chickens.  vitamin d3 benefits -delivery of both TT and inactivated LPAI (H6N2) vaccines in chickens elicited strong TT and influenza-specific antibody responses, which persisted to 53 weeks post-vaccination. Furthermore, immunization with a combined vaccine composed of TT and AI induced high levels of antibodies to both antigens.