TY - JOUR
T1 - Constitutive secretion of chemokines by cultured human trabecular meshwork cells
AU - Shifera, Amde Selassie
AU - Trivedi, Sheetal
AU - Chau, Phuonglan
AU - Bonnemaison, Lucia H.
AU - Iguchi, Rumiko
AU - Alvarado, Jorge A.
PY - 2010/7/1
Y1 - 2010/7/1
N2 - Trabecular meshwork endothelial (TME) cells secrete a number of factors, such as enzymes and cytokines, which modulate the functions of the cells and the extracellular matrix of the conventional aqueous outflow pathway. TME cells usually secrete these factors in response to stimuli such as mechanical stretching, laser irradiation and pro-inflammatory cytokines. Here, we report that cultured human TME cells isolated from two non-glaucomatous individuals secrete significant quantities of the chemotactic cytokines IL8, CXCL6 and MCP1 in the absence of any stimulation. The secretion of these chemokines was augmented by treatment with the pro-inflammatory cytokines TNFα and IL1β. By way of comparison, there was little or very low production of the three chemokines by human non-pigmented ciliary epithelial cells in the absence of stimulation. Our findings provide support to our recent observations that monocytes, presumably under the influence of chemotactic signals, circulate through the trabecular meshwork in the normal state and also that cytokines regulate the permeability of Schlemm's canal endothelial cells. In addition, the fact that normal TME cells constitutively secrete chemotactic cytokines strengthens the notion that cytokines play a key role in the homeostasis of the outflow of the aqueous humor and, possibly, in the pathogenesis of glaucoma.
AB - Trabecular meshwork endothelial (TME) cells secrete a number of factors, such as enzymes and cytokines, which modulate the functions of the cells and the extracellular matrix of the conventional aqueous outflow pathway. TME cells usually secrete these factors in response to stimuli such as mechanical stretching, laser irradiation and pro-inflammatory cytokines. Here, we report that cultured human TME cells isolated from two non-glaucomatous individuals secrete significant quantities of the chemotactic cytokines IL8, CXCL6 and MCP1 in the absence of any stimulation. The secretion of these chemokines was augmented by treatment with the pro-inflammatory cytokines TNFα and IL1β. By way of comparison, there was little or very low production of the three chemokines by human non-pigmented ciliary epithelial cells in the absence of stimulation. Our findings provide support to our recent observations that monocytes, presumably under the influence of chemotactic signals, circulate through the trabecular meshwork in the normal state and also that cytokines regulate the permeability of Schlemm's canal endothelial cells. In addition, the fact that normal TME cells constitutively secrete chemotactic cytokines strengthens the notion that cytokines play a key role in the homeostasis of the outflow of the aqueous humor and, possibly, in the pathogenesis of glaucoma.
KW - CXCL6
KW - Chemokine
KW - Cytokine
KW - IL6
KW - IL8
KW - MCP1
KW - Monocyte
KW - Trabecular meshwork
UR - http://www.scopus.com/inward/record.url?scp=77953582675&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=77953582675&partnerID=8YFLogxK
U2 - 10.1016/j.exer.2010.04.001
DO - 10.1016/j.exer.2010.04.001
M3 - Article
C2 - 20403352
AN - SCOPUS:77953582675
VL - 91
SP - 42
EP - 47
JO - Experimental Eye Research
JF - Experimental Eye Research
SN - 0014-4835
IS - 1
ER -