Clinical and demographic prognostic indicators for human disc cell proliferation in vitro -: Pilot study

Study Design. Human anulus cells were cultured under control and experimental conditions to study associations between proliferation and clinical-demographic features of subjects from which cells were obtained. Statistical multiple regression analyses were applied to develop mathematic models relating proliferation to age, gender, Thompson score (denoting stage of disc degeneration), and status (control donor [postmortem]; surgical patient). Objectives. To identify the effect of donor characteristics on proliferative capacities of human disc cells. Summary of Background Data. As therapeutic options for disc degeneration increase, novel biologic options are important future considerations. Little is known about the influence of clinical-demographic features on cell proliferation. Methods. Anulus cells were studied in two designs: 1) Cells from 12 individuals were grown in monolayer with 50 ng/mL interleukin growth factor-1 (IGF-1), 100 ng/mL insulin, or control conditions. 2) Cells from nine individuals were grown in three-dimensional culture with 10 ng/mL IGF-I or control conditions. Cell proliferation data and data on age, gender, Thompson score, and status were collected. Standard statistical analyses were used to develop correlation models. Results. Data from monolayer experiments produced significant models fitting proliferation in the presence of low serum, 50 ng/mL IGF-I, or insulin, with age, gender, Thompson score, and status (respective R-2: 0.827, 0.680, 0.850). Three-dimensional cultures exposed to 10 ng/mL lGF-I resulted in proliferation that correlated in a significant negative manner with Thompson score (r = -0.798). Conclusions. Clinical-demographic prognostic indicators may help predict levels of proliferation. Greater age, greater disc degeneration, female gender, and surgical derivation had deleterious effects on proliferation potential in this model.