Human mesenchymal stem cell co-culture modulates the immunological properties of human intervertebral disc tissue fragments in vitro

Abstract

The capacity of mesenchymal stem cells (MSCs) to differentiate into intervertebral disc (IVD)-like cells has been well described, but their ability to modulate the inflammatory processes in the IVD remains unclear. We found that tissue obtained by discectomy of degenerated and post-traumatic IVD contains significant amounts of IgG antibodies, a sign of lymphocyte infiltration. Further we investigated whether MSCs in vitro, which were characterized for their multilineage differentiation potential and may have immunomodulatory effects on IVD fragments. IVD fragments were co-cultured in contact with peripheral blood lymphocytes (PBLs) and MSCs, and as functional controls we used contact co-cultures of PBLs stimulated with pokeweed mitogen (2.5 lg/mL) and MSCs. The time course of lymphocyte proliferation (Alamar Blue), IgG (ELISA) and gene expression (RT-PCR) of anti-inflammatory cytokines (TGF-b1, IL-10) by MSCs and proinflammatory molecules (IL-1a, IL-1b and TNF-a) by the IVD fragments were analyzed. Depending on the response to the presence of MSCs, the IVD fragments (n = 13) were divided in two groups: responders (n = 9), where inflammation was inhibited by MSCs and non-responders (n = 4), where MSCs did not decrease inflammation. At 1 week in co-culture, MSCs reduced significantly the IgG production in the IVD responders group to 69% and PBLs proliferation to 57% of the control. MSCs expression of the anti-inflammatory TGF-b1 increased with time, while IL-10 was expressed only at day 1. IVD gene expression of TNF-a decreased constantly, whereas IL-1a and IL-1b expression increased. In conclusion, these data suggest that MSCs may modulate disc-specific inflammatory and pain status and aid regeneration of the host tissue.

Anti-inflammatory Chitosan/Poly-γ-glutamic acid nanoparticles control inflammation while remodeling extracellular matrix in degenerated intervertebral disc

“…One of these includes time in culture to guarantee tissue viability (usually up to 1 week) [39][40][41]. Here, tissue viability maintenance was monitored by mitochondrial metabolic activity and DNA content.…”

Degenerated human intervertebral discs contain autoantibodies against extracellular matrix proteins

“…In an earlier study we have detected IgG antibodies in human degenerated and post-traumatic disc fragments S Capossela et al Autoantibodies in human intervertebral discs cultured in vitro (Bertolo et al, 2011), but we did not identify their targets. Based on the above mentioned data and studies, we put to test the hypothesis that if the integrity of vertebral endplates is compromised by trauma or degeneration, antibodies against disc proteins would be present locally.…”

“…Deposits of immunoglobulin G and M in human disc herniated tissue suggests a correlation between inflammation and autoimmune response (Habtemariam et al, 1996). Furthermore, we have recently shown that significant amounts of IgG antibodies remain in human degenerated and post-traumatic IVDs, despite thorough washing after discectomy (Bertolo et al, 2011). Until now however, there are no studies in humans, which show the specificity of the antibodies present in the disc.…”

Ex vivo observation of human intervertebral disc tissue and cells isolated from degenerated intervertebral discs

“…Several tissue engineering (TE) protocols of the disc have been developed, and the use of mesenchymal cells (MSC) has been shown to be promising, but MSC introduction in the degenerate tissue should be accurately designed using TE strategies, because some adverse effects have been reported [8,9]. This study is the first part of an investigation on the tissue features of IVD retrievals, and ability of disc cell to expand in vitro.…”