Indoleamine 2,3-dioxygenase (IDO) is a tryptophan-degrading enzyme known to suppress antitumor CD8(+) T cells (TCD8). The role of IDO in regulation of antiviral TCD8 responses is far less clear. In addition, whether IDO controls both immunodominant and subdominant TCD8 is not fully understood. This is an important question because the dominance status of tumor- and virus-specific TCD8 may deter...

Acute viral infections typically generate functional effector CD8(+) T cells (TCD8) that aid in pathogen clearance. However, during acute viral lower respiratory infection, lung TCD8 are functionally impaired and do not optimally control viral replication. T cells also become unresponsive to Ag during chronic infections and cancer via signaling by inhibitory receptors such as programmed cell de...

UNLABELLED The factors that determine CD4+ T cell (TCD4+) specificities, functional capacity, and memory persistence in response to complex pathogens remain unclear. We explored these parameters in the C57BL/6 mouse through comparison of two highly related (>92% homology) poxviruses: ectromelia virus (ECTV), a natural mouse pathogen, and vaccinia virus (VACV), a heterologous virus that neverthe...

t lymphocytes that are involved in cellular mediated immunity include two types known as tcd8+ (cytotoxic t lymphocytes) and tcd4+ (helper t lymphocytes). tcd4+ has four main subtypes, including th1, th2, th17, and treg lymphocytes.th17 lymphocytes play a role in defense against microbes that th1 and th2 lymphocytes have not the ability to respond to them. the most important cytokines, which ar...