week 1-5 Flashcards
What cells are the first responders to infection
Myeloid cells
first line of defence?
innate immune cells
Cellular Bridge btw innate and Adaptive immunity?
APCs- Antigen presenting cells
(DCs, B-cells, mf)
——— is the process by which Hematopoietic stem cells (HSC) differentiate into mature RBCs (and leukocytes)
Hematopoiesis
HSCs are directed to differentiate into two major types of progenitors ———— or ——— progenitor cell
HSCs are directed to differentiate into two major types of progenitors lymphoid progenitor cell or myeloid progenitor cell
Failure of Hematopoietic regulatory mechanisms can have seroious consequences such as?
Leukemia
Myeloid progenitor cells diffrentiate into?
mf, DCs, neutrophils, Basophils, Monocytes, Mast cells, WBCs, RBCs
Lymphoid Progenitor cells diffrentiate into?
T-cells, B-cells, NK cells and DCs
Fxn of Myeloid cells
1) detection of pathogens via PRRs
2) phagocytosis
3) escalate imune responses through cytokine and chemokine secretion
——– presence in tissue indicates an active immune response
Granulocytes (neurtorphils, eosinophil, basophils, mast cells)
Provide the major defense against pus-forming (pyogenic) bacteria such as streptococci and staphylococci and fungi?
Neutrophils
cells that make up APCs ?
DCs , macrophages, B-cells, monocytes
fxn of APCs
part of the first line defence against pathogens
* Act as cellular bridges btw innate and Adaptive immunity
fxn of Macrophages
Regulation of the immune response through production of pro-inflammatory (IL-1, TNF, IL-6) and anti-inflammatory (TGFβ, ΙL-10) cytokines
Pro -inflammatory cytokines
IL-1, TNF, IL-6
Anti-inflammatory Cytokines
TGFβ, ΙL-10
Mutation in signaling molecules affecting TLRs will cause?
Recurrent, severe bacterial infections (pneumonia)
Gain of function mutations in inflammasome will cause?
1)Gout
2)Atherosclerosis
3)Type II diabetes
4)Familial Mediterranean Fever (FMF)
NOD2 mutations are associated with enhanced susceptibility to ———-
Crohn’s disease
IL-12 and IFN-γ receptor deficiency will cause?
Increased susceptibility to intracellular infections (mycobacterium tuberculosis)
Fxn of IL-8
neutrophil chemoatractant
———— are released by the liver in resposne to inflammation?
Acute-phase proteins are released by the liver in response to inflammation (IL-6, TNF, IL-1β pro-inflammatory cytokines)
examples of acute-phase proteins released by the liver
CRPs, MBL
Cytokines that maintain granuloma
IFN-γ (produced by the activation of Th cells)
* Also maintains macrophage activation
Cytokine that aids the formation of granulomas
TNF
why is IL-2 given to AIDS patients in combo w/ antiretrovirals
To restore the decreased levels of CD4+ T cells
Fxn of IL-12
1) Promotes the development of CD4+ T cells
2) induces the production of IFN-γ (by activating TH cells)
* Pro-inflammatory cytokine
—- inhibitis Th and Tc activation
anti-CD25 (Ab against IL-2 receptor)
CD25–> IL-12
State the difference in fxn btw granulation tissue and Granulomas
- Granulation tissue : part of the repair response, fxn -> healing of injured tissue
- Granuloms : a form of chronic inflammation, fxn –> phgocytosis
Histology of Granulation tissue
1) Newly formed blood vessles (angiogenesis)
2) Fibroblasts
3) mononuclear cells in extracelluar matrix
(does not surround an indigestible particle like granulomas)
Histology of Granulomas
1) Macrophages (circumsrcibed aggregates of epithelioid cells)
2) surrounded by lymphocytes
3) Giant cells and dead material
Which of the following is a caseating granuloma ; TB or Sarcoidosis
TB
patines w/ severly reduced C3 levels tend to have?
increased numbers of sever Bacterial infection
Diganosis: -
- low CD4+ levels on flow Cytometry
- normal levels of CD8+ cells and B cells
- Hypogammaglobulinemia
- Presenting symtpoms: numerous, severe infections requiring IV antibiotic, diarrhea and oral candidiasis
disroder?
Bare lymphocyte syndrome type 2 aka MHC class II deficiency
- Lack of MHC II due to mutations of regulators of MHC-II transcription (CIITA, RFXANK, RFX5, RFXAP)
- Epi: death at around 4 yrs
* similar diganosis to SCID
Clues in the diagnosis of SCID
1) presents in first few weeks/months of life
2) Infections are often viral/ fungal rather than bacterial
3) Chronic diarrheais common (“Gastroenteritis”)
4) Repiratory infections and oral thrush are common
5) faliure to thrive
6) Lymphopenia (low WBCs)
Diagnosis:
- low CD8+ levels
- Activated NK cells
- normal CD4+ levels
- normal antibody production
Presenting symptoms:
- characteristic mark “necrotizing skin lesions” on the extremities and midface
- Frequent, Bacterial infections of the upper respiratory tract
diagnosis?
Βare lymphocyte syndrome type 1: MHC class I deficiency
cause: lack of expression of TAP1 and TAP2
Cause of Βare lymphocyte syndrome type 1: MHC class I deficiency
lack of expression of TAP1 and TAP2
