Lifelong persistent infection by herpesviruses depends on the balance between host immune responses and viral immune evasion. CD4 T cells responding to antigens presented on major histocompatibility complex class II (MHC-II) molecules are known to play an important role in controlling herpesvirus infections. Here we review, with emphasis on human herpesvirus infections, the strategies evolved t...

Previously, we have demonstrated that during allograft rejection, MHC molecules of the donor are processed and presented to alloreactive CD4+ T lymphocytes in the form of peptides associated with the MHC class II molecules of the recipient. There is an increasing body of evidence that this indirect pathway of allorecognition may play a major role in allograft rejection. Herein, we have used a s...

Legionella pneumophila is a facultative intracellular pathogen that parasitizes host mononuclear phagocytes. Cell-mediated immunity is pivotal to host defense against L. pneumophila, and the infected host cell may play a central role in processing and presenting parasite antigens to lymphocytes mediating cell-mediated immune response. However, in the case of L. pneumophila and intracellular par...

Class II major histocompatibility complex (MHC) molecules present peptides derived from processed antigen to antigen-specific CD4-positive T cells. In addition, class II molecules bind with high affinity another class of antigens, termed superantigens. T cell stimulation by superantigens depends almost exclusively on the V beta segment expressed by the T cell receptor (TCR). Mapping of the supe...

The results of previous biochemical studies indicated that a fraction of MHC class II proteins is associated with four proteins of the tetraspan family, CD37, CD53, CD81, and CD82, and possibly with other membrane components, at the surface of JY B lymphoma cells. In the present communication we used a biophysical technique, namely the flow cytometric energy transfer method, to demonstrate the ...

BACKGROUND Newly synthesised peptide-receptive major histocompatibility complex (MHC) class I molecules form a transient loading complex in the endoplasmic reticulum with the transporter associated with antigen processing (TAP) and a set of accessory proteins. Binding of peptide to the MHC class I molecule is necessary for dissociation of the MHC class I molecule from the complex with TAP, but ...

Recombinant soluble MHC molecules are widely used for visualization, activation and inhibition of antigen-specific immune responses. Using a genetic approach, we have generated two novel peptide–h2-microglobulin–MHC constructs. We have linked the MHC molecule with the peptide of interest, without limiting the recognition by the cognate TCR. This molecule can also be joined with the IgG heavy ch...

Major histocompatibility complex (MHC) class I molecules are cell-surface proteins that present peptides to CD8+ T cells. These peptides are mostly derived from endogenously synthesized protein. Recombinant, soluble MHC class I molecules were produced, purified, and loaded homogeneously with synthetic peptide. These MHC-peptide complexes were used to activate a T cell hybridoma. While monomers ...

The functions of natural killer (NK) cells are controlled by an abundance of activating and inhibitory receptors. Many of these interact with MHC class I molecules. The MHC system also interacts with cytotoxic T-lymphocytes and has been shown to comprise a rapidly evolving family of molecules. This challenges the functional relationship of NK cell receptors with their ligands. Although individu...

One of the important components of the immune system, the major histocompatibility complex (MHC) molecules allow T-lymphocytes to detect cells, such as macrophages, B-lymphocytes, and dendritic cells that ingest infectious microorganisms or the self-cells infected with microorganism. On being engulfed a microorganism, macrophage partially digests it and displays peptide fragments of the microbe...