title: The pattern of interleukin-12 and T-helper types 1 and 2 cytokine expression in herniated lumbar disc tissue.
abstract: METHODS
  A study was conducted to investigate the expression of cytokines related to the immune reaction in herniated lumbar disc tissues.
  
  
  OBJECTIVE
  To investigate the immunologic status of lumbar disc tissue and the type of immune reaction that occurs in response to lumbar disc herniation.
  
  
  BACKGROUND
  It has been proposed that herniated lumbar disc tissue causes an immune reaction. Various inflammatory cells, proinflammatory cytokines, antibodies, and immunoglobulins have been identified in and around herniated lumbar disc tissue. Recently, it has been reported that lumbar disc tissue may be another potential immune-privileged site in the human body.
  
  
  METHODS
  This study included 40 herniated lumbar disc tissues: 20 contained and 20 noncontained discs. The concentrations of interleukin-12, T-helper Type 1, interferon-gamma (IFN-gamma), and Th2 (IL-4) cytokines were determined by enzyme-linked immunosorbent assay, respectively. The results were compared between the two groups.
  
  
  RESULTS
  The concentrations of interleukin-12 and interferon-gamma were higher in the noncontained discs than in the contained discs: 28.3 +/- 10.7 pg/mL vs 9.2 +/- 4.2 pg/mL (P = 0.001) and 4.7 +/- 5.0 pg/mL vs 2.3 +/- 3.8 pg/mL (P = 0.029), respectively. On the contrary, the concentration of IL-4 was higher in the contained discs than in the noncontained discs: 24.3 +/- 20.1 pg/mL vs 1.9 +/- 4.5 pg/mL; P= 0.001. The degrees of interleukin-12 and interferon-gamma expression were negatively correlated with that of IL-4 (n = 40): correlation coefficient, -0.671 (P = 0.001) and correlation coefficient, -0.344 (P = 0.03), respectively.
  
  
  CONCLUSIONS
  The findings suggest that preferential expression of Th2 cytokines by disc cells, as shown in contained discs, is another factor contributing to the immune privileged status of lumbar disc tissue. The exposure of lumbar disc tissue to the epidural space may increase the concentration of interleukin-12 in herniated lumbar disc tissue, changing the pattern of T-helper Types 1 and 2 cytokine expression.
authors.affiliation: Department of Orthopedic Surgery, Uijongbu St. Mary's Hospital, College of Medicine, Catholic University of Korea, Uijongbu-si, Kyunggi-do, Korea. spinepjb@catholic.ac.kr [corrected]
authors.forename: Jong-Beom
authors.initials: JB
authors.lastname: Park
authors.forename: Han
authors.initials: H
authors.lastname: Chang
authors.forename: Yong-Sik
authors.initials: YS
authors.lastname: Kim
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D015704:CD4 Antigens / Q000032:analysis / Q000096:biosynthesis; D016207:Cytokines / Q000032:analysis / Q000096:biosynthesis*; D017586:Diskectomy; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D007371:Interferon-gamma / Q000032:analysis / Q000096:biosynthesis; D018664:Interleukin-12 / Q000032:analysis / Q000096:biosynthesis*; D015847:Interleukin-4 / Q000032:analysis / Q000096:biosynthesis; D007403:Intervertebral Disc / Q000737:chemistry / Q000276:immunology / Q000473:pathology; D007405:Intervertebral Disc Displacement / Q000473:pathology / Q000503:physiopathology* / Q000601:surgery; D008297:Male; D008875:Middle Aged; D018417:Th1 Cells / Q000276:immunology* / Q000473:pathology; D018418:Th2 Cells / Q000276:immunology* / Q000473:pathology
chemical_list: D015704:CD4 Antigens; D016207:Cytokines; D018664:Interleukin-12; D015847:Interleukin-4; D007371:Interferon-gamma