HIV-1 serosubtyping based on reactivity to peptides from the V3 region of gp120 is a low-cost and easy to perform procedure often used in geographical areas with high prevalence and incidence of HIV infection. We evaluated the performance of V3-based serotyping on 148 sera from 118 HIV-1-infected individuals living in Uganda, with estimated dates of seroconversion. Of the 148 tested samples, 68...

The efficient in vitro expansion of antigen-specific CD8+ cytotoxic T lymphocytes (CTL) for use in adoptive immunotherapy represents an important clinical goal. Furthermore, the avidity of expanded CTL populations often correlates closely with clinical outcome. In our study, high-avidity CTL lines could be expanded ex vivo from an antigen-primed animal using low peptide concentration, and inter...

Interaction between antigen and antibody modulates key biological processes in neutralizing and eliminating pathogenic microorganisms following infection. The strength of this interaction depends on the affinity, valency and three dimensional arrangements of the interacting epitopes and paratopes. The measure of the overall strength of this multimeric interaction is termed as ‘Avidity’. Develop...

The presence of high-avidity CTLs in the right compartment can greatly affect clearance of a virus infection (for example, AIDS viral infection of and dissemination from mucosa). Comparing mucosal vs systemic immunization, we observed a novel compartmentalization of CTL avidity and proportion of functionally active Ag-specific CD8(+) T cells to tissues proximal to sites of immunization. Whereas...

Diagnosis of primary human cytomegalovirus (HCMV) infection is accomplished exclusively by serologic testing. Among the possible methods, the determination of immunoglobulin G (IgG) avidity is one of the least explored. In this work, we used a commercially available kit to test anti-HCMV IgG avidity in 336 serum samples from pregnant women and transplant recipients undergoing virologically prov...

Functional avidity of T cells is a critical determinant for clearing viral infection and eliminating tumor. Understanding how functional avidity is maintained in T cells is imperative for immunotherapy. However, studies systematically characterize T cell with high functional avidity induced in vivo are still lacking. Previously, we and others found vaccinia vectored vaccine (VACV) induced antig...

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...

The role of antibody avidity in allergy is poorly understood and there is no existing literature describing antibody avidity in food allergy. The main aim of this study was to investigate IgE and IgG avidity to a total peanut protein extract (TPPE) and purified Ara h 2 in a group of well-characterized peanut allergic individuals. Forty peanut allergic patients underwent a double-blind placebo-c...

The time-dependent increase in the average affinity of serum antibody after immunization (1), is said to be a result of antigen-driven selection of those antibody-forming cell precursors having the highest affinity antigen receptors (2). This interpretation infers that the specificity and affinity of antigen-binding receptors on antibody-forming cell precursors are directly correlated to the se...

The mechanisms whereby different vaccines may expand distinct Ag-specific T cell clonotypes or induce disparate degrees of protection are incompletely understood. We found that several delivery modes of a model retroviral Ag, including natural infection, preferentially expanded initially rare high-avidity CD4(+) T cell clonotypes, known to mediate protection. In contrast, the same Ag vectored b...