Flashcards in Immunology of Joint Conditions Deck (20)
Which immune system is involved in joint diseases?
Adaptive immune system
How does the adaptive immune system have unlimited diversity?
Due to random gene recombination. The random mixing and matching of variable, diversity and joining genes generates unlimited repertoires for pathogens but also self-reactive clones
What are the two types of tolerance of the immune system?
• Central tolerance – strongly self-reactive antibodies die before they leave.
• Peripheral tolerance
What receptor is involved in presenting antigens to T cells?
What are Th1 cells involved in?
Cellular immunity (increased levels can lead to autoimmunity)
What are Th2 cells involved in?
Humoral immunity (increased levels can lead to IgE production and allergy)
What are Th17 cells involved in?
Mucosal surface immunity (increased levels leads to chronic inflammation)
What are Treg cells involved in?
Immune regulation (increased leads to cancer and decreased leads to inflammation autoimmunity)
What is spondylitis?
Inflammation of the joint in the backbone that tends to involve the SI joint
What factors are involved in the pathogenesis of spondylitis?
HLA-B27, T cells and excess TNFa and IL-17 production
What is lupus?
Inflammation of the skin where patients produce auto-antibodies to nuclear antigens
How is lupus associated with arthritis?
Almost all lupus patients develop mild arthritis due to immune complex deposition in blood vessels which activates complement and phagocytic cells
What factors are involved in the pathogenesis of lupus?
Hyperactive immune cells as a result which produce IFN, IFN and B lymphocyte growth factors (e.g. BAFF)
What is the main target in rheumatoid arthritis treatment?
Outline the immunological mechanism behind the pathogenesis of rheumatoid arthritis
> Auto-antibodies to IgG (rheumatoid factors) and citrullinated peptides
> HLA-DR4 presented to T cells
> Excess TNFa production
Name the four aspects of the innate immune system
Lipid mediators, cytokines, chemokine and complement
What is the role of lipid mediators in the innate immune system, and provide examples.
Increase vascular permeability and cause smooth muscle contraction e.g. leukotrienes, PAF and PG
What is the role of cytokines in the innate immune system, and provide examples.
Increase vascular permeability, cause fever and activate vascular endothelium e.g. IL-1, IL-6, IL-8, IL-12 and TNFa
What is the role of chemokines in the innate immune system, and provide examples.
Attract and activate phagocytic cells ad vascular endothelial cells e.g. IL-8, MCP-1 and fractalkine