BACKGROUND Programmed Death-1 (PD-1) is an inhibitory member of the CD28 family of molecules expressed on CD8+ T cells in response to antigenic stimulation. To better understand the role of PD-1 in antiviral immunity we examined the expression of PD-1 on Epstein-Barr virus (EBV) epitope-specific CD8+ T cells during acute infectious mononucleosis (AIM) and convalescence. METHODOLOGY/PRINCIPAL ...

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...

Although it is widely acknowledged that most B-cell epitopes are discontinuous, the degree of discontinuity is poorly understood. For example, given that an antigen having a single epitope that has been chopped into peptides of a specific length, what is the likelihood that one of the peptides will span all the residues belonging to that epitope? Or, alternatively, what is the largest proportio...

The TCR repertoire of an epitope-specific CD8(+) T cell population remains poorly characterized. To determine the breadth of the TCR repertoire of a CD8(+) T cell population that recognizes a dominant epitope of the AIDS virus, the CD8(+) T cells recognizing the tetrameric Mamu-A*01/p11C(,CM) complex were isolated from simian immunodeficiency virus (SIV)-infected Mamu-A*01(+) rhesus monkeys. Th...

CD4 T cells are crucial to the control of Mycobacterium tuberculosis infection and are a key component of current vaccine strategies. Conversely, immune-mediated pathology drives disease, and recent evidence suggests that adaptive and innate responses are evolutionarily beneficial to M. tuberculosis. We compare the functionality of CD4 T cell responses mounted against dominant and cryptic epito...

HNK-1 carbohydrate antigen in an epitope expressed commonly in many cell surface adhesion and recognition molecules in the nervous system. We purified and characterized from rat brain a novel phosphatidylinositol (PI)-anchored 150-kD glycoprotein belonging to the HNK-1 family. The molecule (PI-GP150) was detected by combination of PI-specific phospholipase C treatment of brain membranes and Wes...

Since class I MHC glycoproteins may function by "screening and selecting" degraded proteins, we wished to determine whether very short peptides made within a cell were detected and bound by MHC, and presented for T cell perusal. We show that a 22 amino acid viral sequence containing a Db-restricted nonameric CTL epitope is sufficient to direct CTL recognition/lysis of H2b target cells. The mech...

Recent developments in vaccine construction include the use of attenuated, avirulent strains of Salmonella as carriers of foreign antigens. These recombinant strains can elicit a heterologous immune response when injected into animals, demonstrating potential for their use in the construction of many vaccines. In the present study, a B-cell epitope of Murray Valley encephalitis virus (MVE) was ...

Vaccination strategies for Staphylococcus aureus, particularly methicillin-resistant S. aureus (MRSA) infections have attracted much research attention. Recent efforts have been made to select manganese transport protein C, or manganese binding surface lipoprotein C (MntC), which is a metal ion associated with pathogen nutrition uptake, as potential candidates for an S. aureus vaccine. Although...

The serine proteases, neutrophil elastase (HNE) and proteinase 3 (PR3), are aberrantly expressed in human myeloid leukemias. T-cell responses to these proteins have been correlated with remission in patients with chronic myeloid leukemia (CML). Human PR3/HNE-specific CD8(+) T cells predominantly recognize a nonameric HLA-A2-restricted T-cell epitope called PR1 which is conserved in both Ags. Ho...