Protective immunity against Mycobacterium tuberculosis requires the generation of cell-mediated immunity. We investigated the expression and role of programmed death 1 (PD-1) and its ligands, molecules known to modulate T cell activation, in the regulation of IFN-gamma production and lytic degranulation during human tuberculosis. We demonstrated that specific Ag-stimulation increased CD3+PD-1+ ...

Activated macrophages have been simply defined as cells that secrete inflammatory mediators and kill intracellular pathogens until few years ago. Recent studies have proposed a new classification system to separate activated macrophages based on their functional phenotypes: host defense, wound healing, and immune regulation. Regulatory macrophages can arise following innate or adaptive immune r...

The programmed death-1 (PD-1) molecule is involved in peripheral tolerance and in the immune escape mechanisms during chronic viral infections and cancer. PD-1 interacts with two ligands, PD-L1 and PD-L2. We have investigated the molecular mechanisms of PD-1 interactions with its ligands by surface plasmon resonance and cell surface binding as well as the ability of the two ligands to compete f...