title: Proinflammatory cytokines modulate the chemokine CCL2 (MCP-1) in human annulus cells in vitro: CCL2 expression and production.
abstract: Chemokines are important secondary inflammatory mediators released in response to stimuli which act as second-order cytokines with specialized functions in inflammation. The role of many of these specialized mediators is as yet poorly understood in the human intervertebral disc. Here we investigated CCL2 (chemokine (C-C motif) ligand 2, also known as monocyte chemotactic protein-1 (MCP-1)) in a study of its immunolocalization in disc tissue, and then hypothesized that exposure of cultured human annulus cells to proinflammatory cytokines might alter CCL2 gene expression and CCL2 production. CLL2 was localized to many disc cells in both herniated and non-herniated tissue specimens. Molecular analyses showed that cells exposed to IL-1β showed a 5.5 fold upregulation in CCL2 gene expression vs. controls, p=0.017. Cells exposed to TNF-α showed a 7.7 fold upregulation vs. controls, p=0.005. Cultured cells (grades II-V) showed increased MCP-1 production in IL1-β-treated cells vs. controls (p=0.016), with no significant difference in production in TNF-α-treated cells. Local production of CCL2 in vivo and vitro suggests that annulus cells may be primary effector cells (as well as target cells), with the ability to mediate physiological immune-related processes during disc degeneration by both autocrine and paracrine signaling.
authors.affiliation: Department of Orthopaedic Surgery, Carolinas Medical Center, PO Box 32861, Charlotte, NC, USA. Electronic address: helen.gruber@carolinashealthcare.org.
authors.forename: Helen E
authors.initials: HE
authors.lastname: Gruber
authors.affiliation: Department of Orthopaedic Surgery, Carolinas Medical Center, PO Box 32861, Charlotte, NC, USA.
authors.forename: Gretchen L
authors.initials: GL
authors.lastname: Hoelscher
authors.affiliation: Department of Orthopaedic Surgery, Carolinas Medical Center, PO Box 32861, Charlotte, NC, USA.
authors.forename: Jane A
authors.initials: JA
authors.lastname: Ingram
authors.affiliation: Department of Orthopaedic Surgery, Carolinas Medical Center, PO Box 32861, Charlotte, NC, USA.
authors.forename: Synthia
authors.initials: S
authors.lastname: Bethea
authors.affiliation: Department of Orthopaedic Surgery, Carolinas Medical Center, PO Box 32861, Charlotte, NC, USA.
authors.forename: Michael
authors.initials: M
authors.lastname: Cox
authors.affiliation: Department of Orthopaedic Surgery, Carolinas Medical Center, PO Box 32861, Charlotte, NC, USA.
authors.forename: Edward N
authors.initials: EN
authors.lastname: Hanley
mesh_terms: D000328:Adult; D049109:Cell Proliferation / Q000187:drug effects; D002478:Cells, Cultured; D018932:Chemokine CCL2 / Q000378:metabolism*; D017077:Culture Media, Conditioned / Q000494:pharmacology; D005260:Female; D006801:Humans; D007124:Immunoenzyme Techniques; D066298:In Vitro Techniques; D007223:Infant; D007231:Infant, Newborn; D053583:Interleukin-1beta / Q000494:pharmacology*; D007403:Intervertebral Disc / Q000187:drug effects / Q000276:immunology / Q000378:metabolism*; D055959:Intervertebral Disc Degeneration / Q000188:drug therapy / Q000276:immunology / Q000378:metabolism*; D008297:Male; D046228:Microarray Analysis; D008875:Middle Aged; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology*; D055815:Young Adult
chemical_list: C111835:CCL2 protein, human; D018932:Chemokine CCL2; D017077:Culture Media, Conditioned; D053583:Interleukin-1beta; D014409:Tumor Necrosis Factor-alpha
keywords: CCL2; Cell culture; IL-1α; Intervertebral disc; MCP-1; TNF-β