Major histocompatibility complex class II tetramer staining and activation analysis identified 2 distinct types of antigen-specific CD4+ T cells in the peripheral blood of humans with type 1 (autoimmune) diabetes. T cells with low-avidity recognition of peptide-MHC ligands had low sensitivity to activation and inefficient activation-induced apoptosis. In contrast, high-avidity T cells were high...

BACKGROUND Early diagnosis of congenital toxoplasmosis (CT) is difficult when specific immunoglobulin M (IgM) antibodies are absent, or if persist for months, in the newborn infant's blood. OBJECTIVES To study the risk factors of neonatal toxoplasmosis and to compare different immunologic profiles (Toxoplasma-specific IgM, IgA antibodies and the avidity of IgG antibodies) with polymerase chai...

Congenital toxoplasmosis is associated with important morbidity and mortality. Since vertical transmission of Toxoplasma gondii can occur in acute cases, antenatal screening for recent infections is vital. Accurate determination of acute toxoplasmosis requires a combination of immunoassays, usually not routinely applied for screening purposes. This study evaluated the anti-T. gondii (IgG+IgM)/I...

Induction of antigen-specific CD8(+) T cells bearing a high-avidity T-cell receptor (TCR) is thought to be an important factor in antiviral and antitumor immune responses. However, the relationship between TCR diversity and functional avidity of epitope-specific CD8(+) T cells accumulating in the central nervous system (CNS) during viral infection is unknown. Hence, analysis of T-cell diversity...

Pandemic influenza A H1N1 (pH1N1) virus emerged in 2009. In the subsequent 4 years, it acquired several genetic changes in its hemagglutinin (HA). Mutations may be expected while virus is adapting to the human host or upon evasion from adaptive immune responses. However, pH1N1 has not displayed any major antigenic changes so far. We examined the effect of the amino acid substitutions found to b...

A maternal Toxoplasma gondii infection during pregnancy is a risk for congenital infection through maternal-fetal transplacental transmission. Estimation of the date of infection is of the utmost importance for management and treatment recommendations. In this setting, IgG avidity has been shown to be useful as high avidity rules out an infection dating less than 4 months. The estimated date of...

The proportion of deer mice (Peromyscus maniculatus) with recently acquired Sin Nombre virus (SNV) infections is an indicator of epizootic intensity and may be key in predicting outbreaks of hantavirus cardio-pulmonary syndrome in humans. We investigated whether incidence of recent infections was related to season, sex, reproductive status, or habitat disturbance. In May and September, 2006, we...

The development of effective antitumor immune responses is normally constrained by low-avidity, tumor-specific CTLs that are unable to eradicate the tumor. Strategies to rescue antitumor activity of low-avidity melanoma-specific CTLs in vivo may improve immunotherapy efficacy. To boost the in vivo effectiveness of low-avidity CTLs, we immunized mice bearing lung melanoma metastases with artific...

hemangioma of the rib is a rare benign vascular tumor. herein, we report a 63-year-old man presenting with hemangioma of the left sixth rib. an osteolytic eccentric expansive mass with calcification and focal cortical disruption was detected on chest computed tomography (ct). the mass showed low 2-deoxy-2-[18f]-fluoro-d-glucose (18f-fdg) avidity on positron emission tomography. the patient unde...

PURPOSE We have previously shown that supraoptimal signaling of high avidity T cells leads to high expression of PD-1 and inhibition of proliferation. This study was designed to see if this effect could be mitigated by combining a vaccine that stimulates high avidity T cells with PD-1 blockade. EXPERIMENTAL DESIGN We investigated the anti-tumor effect of a huIgG1 antibody DNA vaccine (SCIB1) ...