Cell Signaling Pathways Immunology PCB 4233 Dr Capers

Cell Signaling Pathways Immunology PCB 4233 Dr. Capers

Jak/Stat Signaling Pathway • Jaks and Stats are critical components of many cytokine receptor systems • Regulates growth of cell • Differentiation • Pathogen resistance • Jak mutations are involved in human hematological malignancies

NF-k. B Signaling Pathway • Nuclear factor-k. B • Regulate expression of genes involved in innate and adaptive immunity, inflammation, B-cell development

Toll-like Receptor Signaling • Innate response – recognize pathogen-associated molecular patterns (PAMPS) • Promote inflammation, proliferation of cells

B Cell Receptor (BCR) Signaling • B cells are antigen presenting cells, promotes presentation of antigen

T Cell Receptor (TCR) Signaling • Promotes cytokine production, proliferation, differentiation

Immune Checkpoint Signaling • Control mechanisms of the immune system, selftolerance • Example is CTLA-4

Apoptosis – Fas/Fas. L Pathway

• Key players: • Jak – Janus Kinase (transfer phosphate groups) • Stat – Signal Transducer and Activator of Transcription • Lck – lymphocyte-specific protein tyrosin kinase • Associates with the tails of CD 4 and CD 8 • Often phosphorylates and activates ITAMS • ITAMs – immunoreceptor tyrosine-based activation motif • found in tails of CD 3 and TCR • Phosphorylation of these allows phosphorylation and activation of ZAP-70 • BTK Tyrosine Kinase • Associates with the B Cell Receptor (BCR) • Activates NF-k. B pathway • FAS (first apoptosis signal) • Part of the TNF family • Found on activated TC cells and NK cells • Caspase – protease enzymes involved in programmed cell death