Immunological Aspects Of The Renal System Flashcards
What are DAMPs and what are some of them?
Molecular patterns/alarmins that induce sterile renal inflammation
HMGB1, uric acid, HSPs, S100 protein, hyaluronans
What are the receptors that respond to PAMPs and DAMPs?
Toll-like receptors, NOD-like receptors, and C-type lectin
What inflammatory response predominates in renal tissue injury in the early stages?
Th17 cells
What inflammatory response predominates in renal tissue injury in the later stages?
Th1 cells
What are M1 macrophages induced by?
PAMPs and DAMPs
IFN-gamma promote differentiation
What induces alternatively activated M2 macrophages?
IL-4 and IL-13
What causes fibrosis and stenosis in chronic states?
M2 cells
What cytokines induce Th17 cells?
TGF beta and IL-6
What cytokine do Th17 cells produce and what is its effect?
IL-17
Tissue inflammation
What are seen in biopsies from patients with glomerulonephritis
Complement proteins
What type 2 hypersensitivity reactions lead to kidney injury?
Patients with anti-glomerular basement membrane (GBM) antibody mediated GN
(Upon damage, positively charged Ags can be planted into the negatively-charged GBM regions)
What are type 3 hypersensitivity reactions that lead to kidney injury?
Post-streptococcal glomerulonephritis, rheumatoid arthritis, and SLE
What occurs downstream of type 2 and 3 hypersensitivity reactions?
Complement activation
What’s the difference between type 2 and type 3 hypersensitivity reactions?
Type 2 = cell-bound antigen
Type 3 = soluble antigen
How quickly does hyperacute rejection occur?
Immediately and caused by antibodies
How quickly does acute rejection occur?
Days to weeks after transplantation and caused by T cells
How quickly does chronic rejection occur?
Months or years after transplantation and caused by vascular trauma, inflammatory products of T cells, Abs
What is an autograft?
Grafts exchanged from one part to another part of the same individual
What is an isograft?
Grafts exchanged between different individuals of identical genetic constitutions (e.g. identical twins)
What is an allograft?
Grafts exchanged between nonidentical members of the sam species
What is a xenograft?
Graft exchanged between members of different species (from animals)
What variables determine transplant outcome?
- The condition of the allograft (better from a live donor)
- Donor-host antigenic disparity
- Strength of host anti-donor response (older recipient is better because weaker immune response)
- Immunosuppressive regimen
What can cause hyperacute allograft rejection?
Mechanical trauma and/or ischemia-reperfusion injury
They can release proinflammatory responses that would damage the graft
What is ABO matching not important for?
Non-vascularized tissues like the cornea, heart valves, and bone/tendon grafts
What antibodies do group A blood types have?
Anti-b
What antibodies do group O blood types have?
Anti-A and anti-B
Are class I or class II HLA Ags a stronger barrier to transplantation?
Class I
What are the immune events in allograft rejection?
- APCs trigger CD4+ and CD8+ T cells
- Both a local and systemic immune response develop
- Cytokines recruit and activate immune cells
- Development of specific T cells, NK cells, or Macrophage-mediated cytotoxicity
- Allograft rejection
What is the difference between host v graft disease and graft v host disease?
Host v. Graft: a kidney is transplanted and the recipient’s T cells attack the transplant
Graft v. Host: bone marrow is transplanted the T cells in the transplant attack the recipient’s tissues
What type of hypersensitivity is hyperacute host vs. graft disease?
Type 2
What type of hypersensitivity is acute host vs. graft disease?
Type 4
What type of hypersensitivity is chronic host vs. graft disease?
Type 4
Why does chronic graft rejection occur?
Due to the occlusion of blood vessels and subsequent ischemia of the organ
Does not respond to immunosuppresive therapy
What kind of hypersensitivity is Graft vs. Host disease?
Type 4
