complement and immune hemolysis

how mant proteins are in the complement system

30+

where are the complement proteins made

in the liver

when are complement proteins active

they are in normal serum, and activated once they are cleaved

what has the highest concentration of beta globulins

C3

how does complement do direct cell lysis

cell surface modifications that lead to rbc cell death

goal of the classical pathway

antigen antibody binding requires calcium to continue the cascade to where it cleaves C4 and C2 forming C3 convertase which cleaves C3.

what Ig type is in the classical complement pathway

mostly IgM

goal of the alternative pathway

bacterial polysaccharides, viral particles, enzymes, endotoxins start being produced and amplification step cleaves C3.

which complement pathway is always active and needs no enzyme

alternative

goal of the lectin pathway

-bacterial polysaccharides, viral particles, enzymes, endotoxins, start being produced

-protein binds to mannose and cleaves C4 and C2

intrinsic hemolysis

is a strictural change in rbc membrane

extrinsic hemolysis is

antibody attack on rbc

extravascular hemolysis happens where

spleen and liver

intravascular hemolysis happens where

inside blood vessels

how is extravascular hemolysis mediated

antibody mediated with or without complement attatched.

-Usually IgG

how are rbc destroyed in extravascular hemolysis

rbc are phagocytized by macrophages in the liver (with C3) or spleen (without C3)

what causes extravascular hemolysis

bound antibody

rbc abnormalities preventing release from spleen

extravascular hemolysis is seen in

delayed hemolytic transfusion reactions

extravascular hemolysis process

-antibodies attatched to rbc antigen are detected by phagocyte

-phagocyte injests the cell

-antibody is removed from the cells causing rbc membrane damage

-rbc becomes a spherocyte with a decreased life span

signs of extravascuar hemolysis

-decreased Hct

-increased bilirubin

-increased LD

-polychromasia

-spherocytes

-fragmented rbc

antibodies that are typically involved in extravascular hemolysis

anti-Rh

-anti-kell

-anti-kidd

-anti-duffy

-anti-S and s

how is intravascular hemolysis mediated

complement mediated

intravascular hemolysis rbc destruction is

basically immediately

Ig type in intravascular hemolysis

IgM antibody that reacts at body temperature

what causes intravascular hemolysis

trauma

complement fixation

other damage to rbc

why can intravascular hemolysis be life threateneing

it can cause anaphylaxis and renal failure

-C5a and C3a are anaphylaxins

intravascular hemolysis process

-two adjacent antigen sites are bound by an antibody which activates complement

-complement pathways produce MAC

-MAC creates a hole in RBC membrane which leads to cell lysis

sign of intravascular hemolysis

-decreased bp

-decreased haptoglobin

-hemoglobinemia

-hemoglobinuria

-ineffective transfusion

-schistocyte

antibodies infolved in intravascular hemolysis

ABO antibodies

anti-I

anti-Lea

anti-A,B

anti-D

anti-Kidd

Anti-kell

auto anti-P