M.L. del Río

HVEM/LIGHT/BTLA/CD160 cosignaling pathways as targets for immune regulation

Immunosuppression is currently the treatment of choice to attenuate the chronic deterioration of tissue function as a result of the effector mechanisms of the immunological response in transplant rejection and autoimmune diseases. However, global immunosuppression greatly increases the risk of acquiring life‐threatening infections and is associated with organ toxicity when used long‐term. Thus, alternative approaches that inhibit only the unwanted immune responses and preserve general immunity are highly desirable. The receptor/ligand pairs involved in the cross‐talk between DC and T cells have been the focus of intense and exciting research during the last decade. The HVEM/LIGHT/BTLA/CD160 costimulatory/coinhibitory pathway has emerged as a potential target for the development of immune therapeutic interventions. Herein, we will summarize and discuss how blockade of the costimulatory HVEM/LIGHT interaction or agonist signaling through the inhibitory BTLA and CD160 receptors could contribute to the control of deleterious immune responses.

Value of Indirect Hemagglutination and Coagglutination Tests for Serotyping Haemophilus parasuis

ABSTRACT An indirect hemagglutination test (IHA) and a coagglutination test (CA) were evaluated using saline, boiled, and autoclaved extracts for serotyping Haemophilus parasuis. CA showed several cross-reactions, whereas IHA gave rise to specific reactions, with minor exceptions. IHA was further compared with the immunodiffusion test (the “gold standard”) for the serotyping of 67 field isolates. As a conclusion, IHA is recommended as a useful method for sensitive and specific serotyping of H. parasuis.

LIGHT/HVEM/LTβR Interaction as a Target for the Modulation of the Allogeneic Immune Response in Transplantation

The exchange of information during interactions of T cells with dendritic cells, B cells or other T cells regulates the course of T, B and DC‐cell activation and their differentiation into effector cells. The tumor necrosis factor superfamily member LIGHT (homologous to lymphotoxin, exhibits inducible expression and competes with HSV glycoprotein D for binding to herpesvirus entry mediator, a receptor expressed on T lymphocytes) is transiently expressed upon T cell activation and modulates CD8 T cell‐mediated alloreactive responses upon herpes virus entry mediator (HVEM) and lymphotoxin β receptor (LTβR) engagement. LIGHT‐deficient mice, or WT mice treated with LIGHT‐targeting decoy receptors HVEM‐Ig, LTβR‐Ig or sDcR3‐Ig, exhibit prolonged graft survival compared to untreated controls, suggesting that LIGHT modulates the course and severity of graft rejection. Therefore, targeting the interaction of LIGHT with HVEM and/or LTβR using recombinant soluble decoy receptors or monoclonal antibodies represent an innovative therapeutic strategy for the prevention and treatment of allograft rejection and for the promotion of donor‐specific tolerance.

Identification of sulI allele of dihydropteroate synthase by representational difference analysis in Haemophilus parasuis serovar 2

Aims:  Identification of genes differentially present in Haemophilus parasuis serovar 2 by representational difference analysis (RDA).