TBPP_C1 Inhibitor

TBPP_C1 Inhibitor

TBPP_C1 Inhibitor


Set of flashcards Details

Flashcards 11
Language English
Category Chemistry
Level University
Created / Updated 30.12.2016 / 30.12.2016
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glycosylation of C1 INH

N-terminal tail heavily glycosylated (35% of MW), strong impact on half-life in plasma, impact of binding of LPS (protection of endotoxic shock), binding to selectins.

purification of C1 INH

cryprecipitation, ion-exchange chr. , (salting out), pasteurization, (salting out), hydrophobic interaction chr., filtration, lyopilization

function of C1 INH

"the complement system", belongs to innate immune system, plasma proteins with several proteases activated only after cleavage (zymogens), 3 major activation pathways: classical, lectin, alternative, attraction of cellls to site of inflammation, attraction for phagocytosis, lysis of cells, shaping of the adaptive immune system, complement disregulation = chronic inflammatory / autoimmune diseases

complement proteins, targets of C1 inhibitor

pattern recognition molecules (C1q, MBL), proteases (C1r, C1s), complement components (C3-C9), complement regulators (C1 INH, MCP), complement receptors (CR1-4), targets of C1 Inhibitor: classical pathway: C1s, C1r (C1Inh form a covalent complex with C1rC1s = inactivation), lectin pathway: MASP1, MASP2, alternative pathway: C3b (prevents C3b deposition)

how to measure complement activity?

hemolytic assays (CH50): sensibilzation of erythrocytes with antibody, incubation, stopp reaction with EDTA, measurements of erythrocytes lysis. complement activation in normal human serum. complement deposition on human endothelial cells. Potentiation of C1 INH activity by glycosaminoglycans

the kallikrein-kinin system

key regulator of vascular permeability and inflammatory processes after tissue injury, released from prekallikrein by activated FXII (Hageman factor), releases bradykinin (which binds B2R) from kininogen, linked with coagulation, firbrinolytic as well as with renin-angiotensin system.

Hereditary Angioedema (HAE) - description

description Osler in 1888, symptoms: edema, start in childhood and persist throughout life, more than 150 different mutations, low levels or abnormal C1 INH, prevalence: 1:50'000, different types of HAE I-III (1: low level, normal function, 2: normal level, low function, 3: not C1 INH dependent, normal level and function, all autosomal dominant)

HAE - therapies

C1 INH: plasma derived or recombinant, kalbitor (kallikrein inhibitor), Icatibant (B-Receptor antagonist)

activities beyond serine protease inhibition

interaction with endogenous proteins (complement, extracellular matrix ECM), interactions with cells (leukocytes, vascular cells), interaction with pathogens (bacteria, parasites)

Ischemia Reperfusion (I/R) Injury

tissue damage and inflammation, when reperfusion (restoration of blood flow) occurs after a period of ischemia (blood occlusion), in solid organ transplantation, stroke, myocardial infarction, tourniquet-applied surgery in extremities/limbs, complement activation, activation of coagulation/contact system, activation of immune cells, generation of reactive oxygen species

rat model of hind limb RI

muscle edema formation, C1 INH prevents edema formation whereas for specific complement inhibitor APT070: no significant reduction observed