PT modifier were not significantly associated with changes in HRQOL measures. CONCLUSIONS: The Schwab-SRS classification of ASD provides a val- idated language and has significant association with HRQOL measures. The current study demonstrates that the classification modifiers are respon- sive to changes in disease state and reflect significant changes in patient reported outcome. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs. http://dx.doi.org/10.1016/j.spinee.2012.08.172 Thursday, October 25, 2012 11:00 AM – 12:00 PM Biologics/Basic Science Seminar and Original Research: Breaking Developments in Disc Biology 82. Resident Stem Cells of the Nucleus Pulposus Are Affected by Tissue Degeneration Dmitriy Sheyn, PhD 1 , Hyun W. Bae, MD 2 , Anthony Oh, Wafa Tawackoli, PhD, Dan Gazit, PhD 3 , Zulma Gazit, PhD 1 ; 1 Cedars-Sinai Medical Center, Los Angeles, CA, US; 2 Spine Institute St. John’s Health Center, Los Angeles, CA, US; 3 Hadassah Medical Center, Jerusalem, Israel BACKGROUND CONTEXT: Intervertebral disc (IVD) degeneration and chronic lower back pain are a major health problem. Since a fundamental understanding of disc degeneration is lacking, robust clinical therapies that target the causes, rather than symptoms, are still in the early development. It was speculated that stem cells (SCs) maintain homeostasis of tissues with a limited regeneration capacity. Changes in the differentiation of res- ident SCs can represent a loss of homeostasis and diminished regeneration of the tissue. We have previously shown that SCs reside in human degen- erated nucleus pulposus (NP) and healthy rat NP. Here we hypothesized that IVD degeneration affects the quantity, proliferation, and differentia- tion potential of resident stem cells in the NP. PURPOSE: The purpose of this study is to investigate the effect of disc degeneration on residual stem cell properties. STUDY DESIGN/SETTING: IVD degeneration was induced and after the degeneration was evident, the discs were harvested and NP-SCs were isolated from healthy and degenerated discs. The stem cell properties of the two groups were evaluated in vitro. OUTCOME MEASURES: The outcome measures in this study were the stem cell properties like self renewal rate and MSC surface markers. Also we have tested the extent of stem cell differentiation in vitro either to mes- enchymal lineages or the NP-like cells. METHODS: Disc degeneration was induced in a mini-pig model by cre- ating an annular injury. Degeneration was verified by MRI 6 weeks after surgery. NP-SCs were isolated from healthy (healthy-NP) and degener- ated discs (degenerated-NP). The freshly isolated cells were tested with a colony-forming unit (CFU) assay. Surface mesenchymal stem cell (MSC) marker expression was examined using FACS analysis and immu- nohistochemistry (IHC). The proliferation rate was evaluated by cell counts made using Trypan blue exclusion and BrdU incorporation. Cell differentiation into mesenchymal lineages was assessed in vitro using von Kossa staining, DMMB assay, and Oil red O staining, respectively. In addition, NP-SCs were differentiated into NP-like cells by culture in alginate beads supplemented with TGFb1 in conditions of hypoxia (2% oxygen) and normoxia for 7 and 14 days. Differentiation was evaluated using GAG quantification with a DMMB assay and ELISA for aggrecan. The expression of aggrecan, collagen II and sox-9 genes was quantita- tively evaluated as well. RESULTS: NP-SCs were isolated from healthy and degenerate IVDs. A significantly higher rate of proliferation was measured in cells from degen- erate-NP by using cell counts and a BrdU assay, and a higher rate of CFUs as well. Freshly isolated SCs from healthy-NP exhibited a higher rate of MSC markers in the FACS analysis. MSC marker expression was verified using IHC in NP tissue. Differentiation assays showed that healthy-NP and degenerated-NP SCs differentiate into the mesenchymal lineages without significant differences between the two groups. Healthy NP-SCs showed a higher differentiation capacity to NP- like cells than degenerated NP-de- rived, in conditions of hypoxia but not normoxia, with higher aggrecan and colII gene expression, higher aggrecan measured in the differentiating cul- ture media and by DMMB assay. CONCLUSIONS: These results indicate that disc degeneration has a clear effect on endogenous SCs in the NP. Cells derived from degenerate discs exhibit higher proliferation abilities that are likely caused by the degener- ation process in the discs. However, although these cells maintain their dif- ferentiation abilities, they have a lower capability of differentiating into NP-like cells. These findings can shed light on the IVD degeneration pro- cess, elucidating what is the role of resident SCs and explaining why these cells are not able to reverse the degeneration. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs. http://dx.doi.org/10.1016/j.spinee.2012.08.125 83. Tobacco Smoke Drastically Upregulates Matrix Metalloproteinase Expression in Disc Cells Upon Suppression of the p38 MAPK Pathway Nam Vo, PhD 1 , Kevin Ngo 2 , Michael J. McKernan 5 , Rebecca Studer, PhD 2 , Joon Y. Lee, MD 3 , Gwendolyn A. Sowa, MD, PhD 4 , James D. Kang, MD 3 ; 1 LJPMC/Ferguson Lab, Pittsburgh, PA, US; 2 Pittsburgh, PA, US; 3 University of Pittsburgh MedicalCenter, Pittsburgh, PA, US; 4 University of Pittsburgh, Pittsburgh, PA, US; 5 Sylvania, OH, US BACKGROUND CONTEXT: Tobacco smoking increases the risk of back pain and intervertebral disc degeneration (IDD), but the mechanism of its adverse action on disc metabolism is not well understood [1, 2]. Loss of disc matrix due to dysregulated activities of matrix metalloproteinses (MMPs) is implicated in initiating the IDD cascade [3]. Tobacco smoke condensate (TSC), containing numerous inflammatory and oxidative stress inducing agents [4], has previously been shown to upregulate MMP expression in disc cells [5]. The p38 MAPK pathway is a central mediator of stress-induced MMP expression [6], but it is not known whether tobacco smoking upregulates MMP in disc cells through this pathway. PURPOSE: Investigate p38 MAPK-mediated regulation of the two major disc MMPs (MMP1, MMP3) in human disc cells exposed to TSC. STUDY DESIGN/SETTING: Laboratory controlled cultures of human annulus fibrosis (hAF) cells exposed to TSE were treated with and without the p38 dominant negative protein to block the p38 MAPK pathway. OUTCOME MEASURES: MMP1 and MMP3 mRNA expression level. METHODS: hAF cells were grown in monolayer culture and transfected for 18-24 hourswith the dominant negative p38aprotein to block the action of this major p38 isoform, and subsequently treated with 0.1 mg/mL total smoke condensate (TSC) for 24 hours. MMP1 and MMP3 mRNA were de- termined by real time semiquantitative RT-PCR and compared to untreated samples. RESULTS: Compared to unexposed control, TSC exposed hAF cells ex- hibited an increase in MMP-1 (74 fold) and MMP-3 (2 fold) mRNA expres- sion. When treated with dominant negative p38aprotein to block the p38 MAPK pathway, TSC exposed hAF cells drastically further upregulated 42S Proceedings of the NASS 27th Annual Meeting / The Spine Journal 12 (2012) 22S–44S All referenced figures and tables will be available at the Annual Meeting and will be included with the post-meeting online content.