AUTOIMMUNITY Flashcards
is a problem of self/non-self discrimination
Autoimmunity
Breakdown of the immune system’s ability to discriminate between self and nonself
Autoimmunity
• A varied group of chronic illnesses that involves almost every human organ system
• Seen when demonstrable immunoglobulins of cytotoxic T cells display specificity for self antigen that contribute to pathogenesis of a cell disorder
Autoimmune disorder
• Characterized by persistent activation of immunologic effector mechanism
Autoimmune disorder
Antigens that do not normally circulate the blood
Altered antigens that arise because of chemical, physical or biological processes.
A foreign Antigen that is shared with self antigen and tissue component
Mutation of immunocompetent cells
Loss of immunoregulatory function of T lymphocyte subset
• The autoimmune response are directed against antigens present only in a particular organ
ORGAN SPECIFIC AUTOIMMUNE DISEASE
• The autoantibodies bind to self antigen to the organ cells and lead to the destruction of cells
ORGAN SPECIFIC AUTOIMMUNE DISEASE
• the autoantibodies bind to self-antigens on cells and lead to either overstimulation of the cell or suppression of the normal functioning of the cells
ORGAN SPECIFIC AUTOIMMUNE DISEASE
• auto antibodies to self- RBCs are formed
AUTOIMMUNE HEMOLYTIC ANEMIA
• The autoantibodies bind to antigens on RBCs and lead to the lysis of RBCs (due to complement activation)
AUTOIMMUNE HEMOLYTIC ANEMIA
• Maybe be caused by drugs (cephalosporins, dapsone)
AUTOIMMUNE HEMOLYTIC ANEMIA
o Acts as haptens (incomplete antigen; needs a carrier RBC)
cephalosporins, dapsone
• The drug-RBC antigen complex induces the immune system to produce antibodies.
AUTOIMMUNE HEMOLYTIC ANEMIA
• Lead to the activation of complement
Other causes of AIHA
• Antibodies reactive to body temperature (37°C)
Warm autoimmune hemolytic anemia
• IgG and complement coats the RBC
Warm autoimmune hemolytic anemia
• Cold reactive IgM reacts with RBC
Cold autoimmune hemolytic anemia
• Room temperature (32°C)
Cold autoimmune hemolytic anemia
• IgG protein reacts with RBC in colder parts of the body producing complement component binding
Paroxysmal cold hemoglobinuria
• a chronic disease resulting from the non-absorption of vitamin B12 (essential for RBC development)
PERNICIOUS ANEMIA
• Results to inability to secrete intrinsic factor (IF)
PERNICIOUS ANEMIA
most common in late adult life
PERNICIOUS ANEMIA
• The basic abnormality of the disease is severe atrophic gastritis
PERNICIOUS ANEMIA
Presence of Intrinsic Factor-blocking antibody is diagnostic of PA
PERNICIOUS ANEMIA
• Autoantibodies to platelets bind to many of the major platelet membrane glycoproteins
IDIOPATHIC THROMBOCYTOPENIC PURPURA
are the major antigens with which the platelet autoantibodies bind
• Platelet GpIIb /IIIa and GPIb/IX
• The antibody coated platelets are destroyed
IDIOPATHIC THROMBOCYTOPENIC PURPURA
• The number of platelets drastically decrease
IDIOPATHIC THROMBOCYTOPENIC PURPURA
• Classic symptoms: petechiae, bruising and bleeding after minor trauma
IDIOPATHIC THROMBOCYTOPENIC PURPURA
• Autoantibodies to certain antigens on the membrane of kidney glomeruli and lung alveoli are formed
GOODPASTEUR SYNDROME
• Complement activation is evident after autoantibody bind membrane antigen
GOODPASTEUR SYNDROME
• This may result in an inflammatory reactions in lungs and kidney
GOODPASTEUR SYNDROME
• The kidneys may be damage or patients may suffer from pulmonary hemorrhage
GOODPASTEUR SYNDROME
• Bleeding in the lungs are seen
GOODPASTEUR SYNDROME
• Chronic autoimmune thyroiditis
HASHIMOTO’S THYROIDITIS
• Autoantibodies against many thyroid proteins and T cells are formed
HASHIMOTO’S THYROIDITIS
• Clinical picture:
o Goiter
o Hypothyroidism
o Thyroid autoantibodies
o Hyperplasia
HASHIMOTO’S THYROIDITIS
Symptoms of hypothyroiditis
Dry skin, decrease sweating, puffy face, edematous eyelids, weight gain (decrease in T3 and T4 slows down metabolism) and brittle hair
• Autoantibodies on thyroid stimulating hormone (TSH) receptors bind to TSH receptors on thyroid
GRAVE’S DISEASE