Staphylococcal protein A primed leukocytes enhance the autologous mixed lymphocyte reaction

The keratinocyte as a target for staphylococcal bacterial toxins

Skin infections with Staphylococcus aureus are not only an important cause of morbidity and even mortality, but are thought to serve as initiation and/or persistance factors for numerous inflammatory skin diseases, including psoriasis and atopic dermatitis. One mechanism by which S. aureus can modulate the immune system is through the production of proteins such as superantigenic toxins, Protein A, as well through the cytolytic alpha-toxin. This review serves to discuss the biology of these three types of proteins, with emphasis on their ability to stimulate the production of powerful pro-inflammatory lipid- and protein-derived cytokines in keratinocytes. Characterization of interactions between these proteins and the keratinocyte can provide a better understanding of how bacterial infection modulates inflammatory skin diseases, as well as provide the basis for improved therapies involving antibacterial agents.

Tannic-acid staining material on high endothelial venules and lymphocytes in skin and peripheral lymph nodes in Staphylococcus aureus-associated erythroderma

The recognition and binding of glycoprotein receptors on lymphocytes to specific antigens present on high endothelial venules (HEV) precedes the egress of lymphocytes from the blood stream into the tissues. In this paper, we report the presence of HEVs with tannic-acid staining material (TASM+ HEVs) in Staphylococcus aureus-associated erythroderma, which allow the migration of CD8+ lymphocytes from the bloodstream into the epidermis. TASM positivity is also expressed on lymphocytes within the regional lymph nodes, and by intravascular lymphocytes prior to leaving the TASM+ HEV. It is proposed that TASM positivity may represent a molecule, which may function in binding lymphocytes to HEVs prior to egress from the HEV. (TASM is lost from lymphocytes after leaving the HEVs). The expression of TASM positivity may form an essential part of the CD8+ lymphocyte-HEV recognition system, and may be the means whereby CD8+ lymphocytes generated in the regional lymph nodes by various mitogens (in this case by staphylococcal mitogens) may 'home' to specific sites within the epidermis. TASM positivity on both the HEVs and lymphocytes may serve as a convenient marker of such a system.