CTL that possess a high functional avidity are known to be optimal for the clearance of pathogens in vivo. We have shown that the amount of peptide encountered by a CD8+ CTL determines its functional avidity. Notably, in these studies nonprofessional APC were used. However, it is mature dendritic cells (DC) that are predominantly responsible for the activation of naive T cells in vivo. Whether ...

We review recent advances toward a comprehensive mathematical theory of T-cell immunity. A key insight is that the efficacy of the T-cell response is best analyzed in terms of T-cell receptor (TCR) avidity and the distribution of this avidity across the TCR repertoire (the 'avidity spectrum'). Modification of this avidity spectrum by a wide range of tuning and tolerance mechanisms allows the sy...

During the course of the immune response to dinitrophenylated guinea pig albumin (DNP-GPA), a striking and parallel increase in avidity for epsilon-DNP-L-lysine occurs in the receptors on antigen-binding lymphocytes, antibody secreted by individual plaque-forming cells, and serum antibody molecules. A detailed analysis of the avidity distribution of antibody produced by plaque-forming cells ind...

Antibody avidity, the strength of the multivalent interaction between antibodies and their antigens, is an important characteristic of protective immune responses. We have developed an inhibition enzyme-linked immunosorbent assay (ELISA) to measure antibody avidity for the capsular polysaccharide (PS) of Neisseria meningitidis group C (MnC) and determined the avidity constants (K(D)s) for 100 s...

Antibody avidity for antigens following disease or vaccination increases with affinity maturation and somatic hypermutation. In this study, we followed children and adults in Bangladesh for 1 year following oral cholera vaccination and measured the avidity of antibodies to the T cell-dependent antigen cholera toxin B subunit (CTB) and the T cell-independent antigen lipopolysaccharide (LPS) in c...

Thymocyte maturation is governed by antigen–T cell receptor (TCR) affinity and the extent of TCR aggregation. Signals provided by coactivating molecules such as CD4 and CD28 also influence the fate of immature thymocytes. The mechanism by which differences in antigen–TCR avidity encode unique maturational responses of lymphocytes and the influence of coactivating molecules on these signaling pr...

While activated T cells are known to have enhanced biological responses to antigen stimulation, the biophysical basis of this increased sensitivity remains unknown. Here, we show that, on activated T cells, the TCR avidity for peptide-MHC complexes is 20- to 50-fold higher than the TCR avidity of naive T cells. This increased avidity for peptide-MHC depends on TCR reorganization and is sensitiv...

AIM To determine the value of tests for specific IgA, IgE, and IgG avidity in diagnosing Toxoplasma gondii infection during pregnancy. METHODS In a retrospective study, current serological tests (dye test and three IgM assays with different sensitivities) were compared with immunosorbent agglutination assays (ISAGA) for specific IgA and IgE and an IgG avidity enzyme linked immunosorbent assay...

introduction: aflatoxin b1 (afb1) is one of the most well-known hepatocarcinogens in humans. contamination of raw materials, used in the production of sausages and burgers, with aflatoxin producing molds can lead to increased level of aflatoxin in the final products and can impose hazards to human health. unfortunately, aflatoxin is resistant to heating and freezing processes, etc. and can rema...

objective: a descriptive study was carried out to determine the significance of igg-affinity in the serological diagnosis of rubella infections in pregnancy. materials and methods: a total of 92 pregnant women who had never received antirubella vaccines were recruited by simple random selection and did not exceed 24 weeks of gestation were recruited from the antenatal clinics of the university ...