Immunodef. Flashcards
B-cell defects
Individuals healthy 7-9mths postpartum, then there are transient low IgG levels. Suseptible to recurrent bacterial and fungal infections.
Aggamaglobulinemia
Low Ig levels. Diagnosed by ELISA and quanitity B cell number.
Bruton’s XLA
Bruton’s X-linked agammaglobulinemia. More prevalent in males, greatly reduced number of B cells due to them being immature.
Lack enzyme for B cell maturation due to mutant tyorosine kinase.
Non-Bruton’s aggamaglobulinemia
Equal in men and women.
Autosomal defects in B cell maturation signalling.
Hyper IgM syndromes
All defects in class switching, many in hypermutation.
Most common defect in CD40L/CD40 so can’t interact with Th cells.
Lack of IgG and IgA, so opportunistic infections.
CVID
Common variable immunodeficiency.
Impaired Ab response.
Low levels of IgA and IgG.
Hyper IgE-aberrant isotype.
SCID
Severe combined immunodeficiency diseases.
No effective T/B cell response.
Inevitably fatal untreated without BMT/HCT.
Possible Th defects.
With Th1, Th2, T-reg cells.
MHC defects.
Autoimmune lymphoproliferative disease
Excess proliferation of B and T cells and immature thymocytes
Dye to defects in apoptopic machinery
X-linked lymphoproliferative disease
Excess IFN-gamma leads to excessive Th1 skew and proliferation of B lymphocytes after EBV infection.
Leukocyte adhesion deficiency I-III
Lack mechanism for migration
Chronic granulomatous disease
Can’t produce superoxide for phagasome killinh
Chediak-Higashi Syndrome
Defect in organelle fusion, some immune cells can’t kill
When do autoimmune disease occur>
Tolerance breaks down.
Trauma releases previously unseen antigens, e.g the eye.
Molecular mimicry.
Genetic factors.
Insulin dependent diabetes
Beta islet cells damaged by inflammatory macrophages. C, T or beta cells destroy T cells reactive against insulin found in islet cells.
Multiple sclerosis
Myelin sheath destroyed around nerve axons by T cells and inflammatory macrophages.
What causes MS?
Damage, EBV infection, genetics.
Grave’s disease
Abs against thyroid stimulating hormone receptor cause over production of thyroxine.
Symptoms of Grave’s
Weight loss, tremors, rapid HR, buldging eyes
