Superantigen-presentation by rat major histocompatibility complex class II molecules RT1.Bl and RT1.Dl

Toxic Shock Syndrome: A Literature Review

Toxic shock syndrome (TSS) is a rare, life-threatening, toxin-mediated infectious process linked, in the vast majority of cases, to toxin-producing strains of Staphylococcus aureus or Streptococcus pyogenes. The pathophysiology, epidemiology, clinical presentation, microbiological features, management and outcome of TSS are described in this review. Bacterial superantigenic exotoxins induces unconventional polyclonal lymphocyte activation, which leads to rapid shock, multiple organ failure syndrome, and death. The main described superantigenic exotoxins are toxic shock syndrome toxin-1 (TSST-1) and enterotoxins for Staphylococcus aureus and Streptococcal pyrogenic exotoxins (SpE) A, B, and C and streptococcal superantigen A (SsA) for Streptococcus pyogenes. Staphylococcal TSS can be menstrual or nonmenstrual. Streptococcal TSS is linked to a severe group A streptococcal infection and, most frequently, to a necrotizing soft tissue infection. Management of TSS is a medical emergency and relies on early detection, immediate resuscitation, source control and eradication of toxin production, bactericidal antibiotic treatment, and protein synthesis inhibiting antibiotic administration. The interest of polyclonal intravenous immunoglobulin G administration as an adjunctive treatment for TSS requires further evaluation. Scientific literature on TSS mainly consists of observational studies, clinical cases, and in vitro data; although more data on TSS are required, additional studies will be difficult to conduct due to the low incidence of the disease.

Analysis of antigen-presenting functionality of cultured rat hepatic stellate cells and transdifferentiated myofibroblasts

Here, we demonstrate that hepatic stellate cells (HSC) isolated from Lewis rats have in vitro antigen-presentation cell (APC) functionality and are able to process and present exogenous antigens. We show activation of a major histocompatibility complex II (RT1BI)-restricted T-cell hybridoma specific for guinea pig myelin basic protein (gpMBP) after coculture with HSC. During transdifferentiation of HSC into myofibroblasts (MFB) the APC function was markedly decreased but restorable by addition of interferon-gamma (IFN-gamma). Based on our findings we conclude that HSC play a key role in hepatic immune function and that IFN-gamma treatment might mediate its beneficial therapeutic effects via activation of APC function in MFB.