Cytokines

Cytokines are proteins secreted by cells that serve as intercellular mediators (see Table 57-1). An imbalance of proinflammatory and anti-inflammatory cytokines in the synovium leads to inflammation and joint destruction. The proinflammatory cytokines interleukin 1 (IL-1), tumor necrosis factor-a (TNF-a), IL-6, and IL-17 are found in high concentration in synovial fluid. These proinflammatory cytokines cause the activation of other cytokines and adhesion molecules responsible for the recruitment of lymphocytes to the site of inflammation. Anti-inflammatory cytokines and mediators (IL-4, IL-10, and IL-1 receptor antagonist) are present in the synovium, although concentrations are not high enough to overcome the effects of the proinflam-matory cytokines.4,9

Table 57-1 Cytokines Involved in the Pathogenesis of RA

Cytokine

SMW

Activity

Proinflammatory

TNF-a

MacropKvjei, moncr/tief. R lymphocyte?,

Indices IL-l.U-6. Il-H, siimuljie* fibroblasts to

T lympixxytes, Fibroblasts

release adhesion molecules

L-l

uaaophic)«, moncïifiici,(fldi3twlii c^fc.

ttiiiiul.Wdihtrtïl.Wt JrUifhiïi(1i[X>T« to ri'liMU^ rtVilrix

fl tyiT y!«, activated T lymphocytes

metallopioieina-ws

H

T lymp'iCi yies irtOrKuy!«! «rut nophù^ei, synOfijl

*s.tivjHr> T lymplux y1e\. 1ndu<tl*CUte-ptlHeiHp0ftS4

fitrfHjblîiii

stimulate! oiiïAih and differentiation of hematopoleiic piecursor cells, stimulates synovial fibtoblasts

■L-l?

T lympltKX yTÎ^ in ^yflflviym

SylVrilbIt tff«l will' H I -irhh TNJ li'.ul to irtf ii'.im^J pioducllonof proinflammatory cytokines

Anti-lnrUmmKory

CP4-+- iype 1 help« T lymphocyte*

irihihu af livattem of type 1 helper T lymphocytes ClMltdSM piOduCtkiitOf IL-1. TNF fl.lt-6.fl.-B

L-K>

Monocytes. maciophsçt«. 6 lymphocyte?.

Inhibits pioduciionof IL-1. TNF-a and prolifération of T

T lymphocytes

lymphocytes

Anxiety and Depression 101

Anxiety and Depression 101

Everything you ever wanted to know about. We have been discussing depression and anxiety and how different information that is out on the market only seems to target one particular cure for these two common conditions that seem to walk hand in hand.

Get My Free Ebook


Post a comment