Association and virulence gene expression vary among serotype III group B streptococcus isolates following exposure to decidual and lung epithelial cells.

Group B Streptococcus (GBS) causes severe disease in neonates, the elderly, and immunocompromised individuals. GBS species are highly diverse and can be classified by serotype and multilocus sequence typing. Sequence type 17 (ST-17) strains cause invasive neonatal disease more frequently than strains of other STs.

The cytosolic endopeptidase, thimet oligopeptidase, destroys antigenic peptides and limits the extent of MHC class I antigen presentation.

Most antigenic peptides presented on MHC class I molecules are generated by proteasomes during protein breakdown. It is unknown whether these peptides are protected from destruction by cytosolic peptidases. In cytosolic extracts, most antigenic peptides are degraded by the metalloendopeptidase, thimet oligopeptidase (TOP).

Distinct proteolytic processes generate the C and N termini of MHC class I-binding peptides.

Most of the MHC class I peptides presented to the immune system are generated during the course of protein breakdown by the proteasome. However, the precise role of the proteasome, e.g.

Activation of rat macrophages by Betafectin PGG-glucan requires cross-linking of membrane receptors distinct from complement receptor three (CR3).

PGG-glucan (Betafectin) is a soluble, highly purified yeast (1,3)-beta-glucan with broad anti-infective and immunomodulatory activities. These studies evaluated the ability of PGG-glucan to directly elicit O2- and tumor necrosis factor alpha (TNF-alpha) production by rat leukocytes in vitro. Particulate beta-glucan stimulated O2- production by the rat NR8383 alveolar macrophage cell line and resident rat peritoneal macrophages, but soluble PGG-glucan did not.