Immunodeficiency Flashcards
List the pattern recognition receptors (PRRs).
- Toll-like receptors (TLR’s)
- NOD-like receptoes (NLR’s)
- Rig-like receptors (RLR’s)
- C-type lectins (CLR’s)
- scavenger receptors
What types of antimicrobial peptides are involved in the innate immune response?
- defensins
- cathelin
- protegrin
- granulsyin
- histatin
- secretory leukoprotease inhibitor
- probiotics
Which cells are involved in the innate immune response?
- Macrophages, dendritic cells, NK cells, NK-T cells, neutrophils, eosinophils, mast cells, basophils, and epithelial cells
What is immunodeficiency?
- Clinical situations where the immune system is not effective enough to protect the body against infection
- Can occur at any age.
What might be the cause of immunodeficiency?
- Can be argued that infection is always the result of transient immunodeficiency.
- Usually secondary to the effects of external factors
- Some are primary immunodeficiencies caused by genetic defects in individual components of the immune system.
- The type of infection is a guide to underlying cause.
- Laboratory tests confirm.
What are the causes of secondary immunodeficiencies?
- Stress (release of endogenous steroids - glucocorticoids)
- Surgery/burns
- Malnutrition
- Trauma (release of steroids)
- Cancer – especially lymphoproliferative disease
- Immunosuppressive effect of drugs inc. cancer therapy
- Lymphocytes
- Neutrophils
What is the root cause of a primary immunodeficiency?
Genetic defect - i.e. lacking any protein involved in inflammation, innate/acquired immunity
What is chronic granulomatous disease?
- Inability to acidify phagosome or form reactive oxygen species - leads to deep-seated bacterial infections e.g.
- Osteomyelitis
- Pneumonia
- Swollen lymph nodes
- Ginigivitis
- Non-malignant granulomas
- Inflammatory bowel disease
What kind of infections do terminal complement pathway deficiencies make a person susceptible to?
Meningococcal
What are the features of B cell deficiency?
- Lead to different degrees of loss of antibody secretion.
- Usually leads to recurrent bacterial infection with pyogenic organisms.
- Usually diagnosed at around 1-2 years since maternal IgG protects.
- Treat with antibiotics then iv IgG For life.
- Most are very serious
- some less serious e.g IgA deficiency.
Why are T cell deficiencies usually more dramatic than B cell deficiencies?
- Usually more dramatic since B cells also need T cell help.
- Symptoms are recurrent infection with opportunistic infections, bacteria, viruses,
- Fungi (candida), protozoa (pneumocystis).
What is severe combined immunodeficiency disorder (SCID)?
- Defect in both B and T cells
What are the primary T cell deficiencies?
- Severe Combined Immunodeficiency syndromes
- Adenosine Deaminase Deficiency
- Purine Nucleoside Phosphorylase Deficiency
- MHC Class II Deficiency
- Wiskott-Aldrich Syndrome
What are the primary B cell deficiencies?
- Common Variable Immunodeficiency
- X-linked agammaglobulinaemia
- Autosomal recessive Hyper IgM syndrome
- IgA Deficiency
- IgG Subclass Deficiency
- Transient Hypogammaglobulinaemia of infancy
What procedure can provide a cure in SCID?
Bone marrow transplant
Defects in what lead to susceptibilty to pneumococcus and HSV?
PRRs
Deficiencies of which cells lead to susceptibility to aspergillus, staphylococcus and CGD?
Macrophages and neutrophils
Defects in which cells lead to recurrent sino-pulmonary infections?
B cells
Defects in what lead to susceptibility to mycobacterium?
Certain cytokines
