Expression of streptococcal M protein in mammalian cells.

Superantigenicity of streptococcal M protein

M proteins that define the serotypes of group A streptococci are powerful blastogens for human T lymphocytes. The mechanism by which they activate T cells was investigated and compared with the conventional T cell mitogen phytohemagglutinin, and the known superantigen staphylococcal enterotoxin B. Although major histocompatibility complex (MHC) class II molecules are required for presentation, ...

M protein mediates streptococcal adhesion to HEp-2 cells.

Streptococcus pyogenes adheres to human epithelial cells in vitro and in vivo. To identify adhesins, cell wall components were extracted from S. pyogenes M6 with alkali or by treatment with mutanolysin and lysozyme. HEp-2 cells were incubated with extracts of S. pyogenes M6 and then analyzed by Western blot (immunoblot) assays, using antibodies to S. pyogenes. Only one streptococcal component (...

Functional and Developmental Analysis of CD4+CD25+ Regulatory T Cells under the Influence of Streptococcal M Protein in Rheumatic Heart Disease

The purpose of this study was to determine the role of streptococcal M protein in naturally-occurring CD4+CD25+ regulatory T cells (nTregs) function and development in rheumatic heart disease in Iraqi patients. Streptococcus pyogenes was isolated for subsequent M protein extraction. Also, peripheral blood nTregs and CD4+ T cells were isolated by using Magnetic Cell Separation System. Tissue cul...

PepGMV Rep-Protein Expression in Mammalian Cells

The Geminiviruses genome is a small, single strand DNA that replicates in the plant cell nucleus. Analogous to animal DNA viruses, Geminiviruses depend on the host replication machinery to amplify their genomes and only supply the factors required to initiate their replication. Consequently, Geminiviruses remove the cell-cycle arrest and induce the host replication machinery using an endocycle ...

Expression of Biologically Active Recombinant B-Domain-Deleted Human Factor VIII in Mammalian Cells