15. COMPLEMENT SYSTEM

76問 • 2年前

問題一覧

Series of more than 30 soluble and cell-bound proteins (proteinases)that interact in a very specific way to enhance host defense mechanisms.

COMPLEMENT SYSTEM

nature of complement DISCOVERED BY:

Jules Bordet

COMPLEMENT SYSTEM Production: MOST ARE PRODUCED in the ________

LIVER

Functions: a. Opsonization

COMPLEMENT SYSTEM

Functions: Cell lysis (end product of Complement)

COMPLEMENT SYSTEM

Functions: Inflammation (via anaphylotoxin)

COMPLEMENT SYSTEM

Inflammation (via ? )

anaphylotoxin

(end product of Complement)

Cell lysis

Functions: Chemotaxis

COMPLEMENT SYSTEM

Functions: NOT A VIRAL

COMPLEMENT SYSTEM

Classical  Triggered by:

Ag-Ab complex

Triggered by: Ag-Ab complex

Classical

MOST EFFICIENT TO FIX COMPLEMENT

Ab: IgM

HOW MANY IgM – IN CLASSICAL PATHWAY

ONE

IgG – must be at least ?

two

– must be at least two

IgG

CAUSES GENERATION OF PLASMIN TO ACTIVATE COMPLEMENT; TRIGGER BY PRODUCING PLASMIN

Hageman Coag factor

Classical Additional initiator

CRP, mycoplasma AND E COLI

Classical 3 Main Stages

Recognition Activation/ Amplification MAC (membrane attack complex)

MAC (membrane attack complex)

C5-C9

MAC (membrane attack complex)

Recognition –

C1 (C1qrs)

what site? – C1 (C1qrs)

Recognition

C1- ________ complement, stabilized by ________

HEAVIEST; CALCIUM + MG

- HEAVIEST complement, stabilized by CALCIUM + MG

C1q – recognizes ________ of two Adjacent Ab

– recognizes FC of two Adjacent Ab

C1q

– zymogens; INACTIVE

C1rs

Activation/ Amplification –

C4, C2, and C3

– C4, C2, and C3

Activation/ Amplification

– SECOND most abundant complement in classical pathway

C4b- 1st ________ step

AMPLIFICATION

- 1st AMPLIFICATION step

C4b

C4b2a –

C3 convertase

in Classical pathway– C3 convertase

C4b2a

– MAJOR constituent of the complement system

PIVOTAL point for all 3 pathways

is the most SIGNIFICANT step in the entire process in alternative pathway

cleavage of C3 to C3b

represents a SECOND and major amplification process

Cleavage of C3

C4b2a3b – C5 convertase, ________ step in the formation of the activation unit.

LAST

– C5 convertase, LAST step in the formation of the activation unit in classical pathway

C4b2a3b

C4b2a3b – ?, LAST step in the formation of the activation unit.

C5 convertase

the beginning of MAC

C5b

Splitting of C3 and C5 represents the most significant biological consequences of the complement system

MAC (membrane attack complex)

- starts pore formation

– tubular pore that causes cell lysis to nucleated cells. Last stage of MAC

MAC 2 Mechanisms

Channel formation Binding of phospholipids

–MOST POTENT and also a chemotaxin

C5a

– Least effective anaphylatoxins

C4a

– kinin-like activity

C2b

– powerful opsonin

C3b and C4b

Non-Ab-initiated pathway

Alternative (Properdin)

described by Pillemer

Alternative (Properdin)

Alternative (Properdin) described by

Pillemer

Triggered by: Bacterial cell wall: LPS, fungal cell wall (zymosan), yeast, virus, virally infected cells, tumor cell lines, and parasites (trypanosomes); Aggregated IgG2, IgA, and IgE; In PNH –triggered by RBC ->Lysis

Alternative (Properdin)

Alternative (Properdin) Triggered by: ?

Bacterial cell wall: LPS

pathway which is Innate Immunity

Alternative (Properdin)

–was the 1st protein to function in Alternative

Properdin

– major CONTROLLING event in ALTERNATIVE PATHWAY

Factor H

Factor D -> Cleaves

Factor B

-> Cleaves Factor B

Factor D

C3 is continuously hydrolyzed by water -> C3b + Factor B = ________

C3bBb

C3 is continuously hydrolyzed by water -> C3b + Factor B = C3bBb + P = C3bBbP -> cleaves more C3 = ______ -> has high affinity for C5 -> beginning of MAC

C3bBb3b

? -> STABILIZE C3 convertase in alternative pathway

Properdin

ALTERNATIVE PATHWAY Properdin -> STABILIZE ?

C3 convertase

Lowest concentration among complement proteins

Alternative (Properdin)

Triggered by: recognition of carbohydrate on microbial cell wall

MBL (lectin)

OUR PROTECTION WHEN WE ARE STILL A BABY

lectin

MBL (lectin) is dependent in

CALCIUM DEPENDENT

– proteins that bind to carbohydrates

Lectins

– binds to mannose. Is considered acute phase reactant.

MBL (mannose-binding lectin)

MBL (mannose-binding lectin) – binds to mannose. Is considered ?.

acute phase reactant

MBL (lectin) Production:

Liver

Infant defense mechanism

MBL (lectin)

deficiency of MBL

neonatal pneumonia and sepsis.

MBL (lectin) - unclear

MASP 1 and MASP 3

other names parasitology

Yves Laure Pimentel · 70問 · 2年前

other names parasitology