Chapter 14- Type II Alergies

type II hypersensitivities

reactions that lyse foreign cells

IgG, IgM, transfusion, donations, hemolytic

Syndromes where host ____ and _____ antibodies target foreign cell surface antigens which results in complement-assisted destruction (lysis) of the targeted cells:

• _______ reactions and organ ________

• _______ disease of the newborn

• Some types of autoimmunities

alloantigens

Present in some, but not all members of the same species

donor cells

_______ _______ may have different surface alloantigens that are that are recognized as foreign by host lymphocytes; this is a normal immune reaction to a foreign cell

Rh factor, Rh+, Rh-, transfusion

First discovered in experiments exploring genetic relationships among animals:

• Monkey antigen (Rh for rhesus) present in ~85% of humans (absent in ~15%)

• ____ is dominant gene; ______ is recessive

• Antibodies only develop against this through exposure to fetus’s antigen or by ________

placental sensitization, RBCs, placenta, foreign, late

In hemolytic disease: occurs when the mother is Rh- and the unborn child is Rh+

• Fetal ______ leak into motherʼs circulation during childbirth when the _______ detaches

• Motherʼs immune system detects _____ Rh factors on fetal RBCs

• Does not usually affect the first child because the process occurs so ______ in pregnancy

memory response, complement mediated lysis, hemolytic disease of the newborn

hemolytic disease: in the next pregnancy with an Rh+ fetus:

• Late in pregnancy, fetal blood cells escape into maternal circulation, eliciting a ________ _______

• Maternal anti-Rh antibodies cross placenta and cause _______-______ _____ of fetal RBCs

• •Causes potentially fatal ____________ (HDN), characterized by severe anemia and jaundice

sensitization

In hemolytic disease of the newborn:

• Once ________ has occurred, all other Rh+ fetuses will be at risk

• Prevention requires careful history of Rh^– pregnant women

RhoGAM antiserum

• Must be given with each pregnancy with Rh- mother and Rh+ fetus

• sequesters fetal RBCs that have escaped into maternal circulation and prevents sensitization