Cell based therapies are attractive approaches to promote myelin repair. Recent studies demonstrated a reduction in disease burden in mice with EAE treated with mouse mesenchymal stem cells (MSCs). Here we demonstrated human bone marrow derived MSCs (BM-hMSCs) promote functional recovery in both chronic and relapsing-remitting models of mouse EAE, traced their migration into the injured CNS and assayed their ability to modulate disease progression and the host immune response. Injected BM-hMSCs accumulated in the CNS, reduced the extent of damage and increased oligodendrocyte lineage cells in lesion areas. The increase in oligodendrocytes in lesions may reflect BM-hMSC induced changes in neural fate determination since neurospheres from treated animals gave rise to more oligodendrocytes and less astrocytes than non-treated neurospheres. Host immune responses were also influenced by BM-hMSCs. Inflammatory T-cells including interferon gamma (IFN-γ) producing Th1 cells and IL-17 producing Th17 inflammatory cells and their associated cytokines were reduced along with concomitant increases in IL-4 producing Th2 cells and anti-inflammatory cytokines. Together these data suggest the BM-hMSCs represent a viable option for therapeutic approaches.

No abstract

Patients with locally advanced and metastatic urothelial carcinoma have a low survival rate (median 15.7 months, 13.1-17.8), with only a 23% response rate to monotherapy treatment with anti-PDL1 checkpoint immunotherapy. To identify new therapeutic targets, we profiled the immune regulatory signatures during murine cancer development using the BBN carcinogen and identified an increase in the expression of the T cell inhibitory protein B7-H4 (VTCN1, B7S1, B7X). B7-H4 expression temporally correlated with decreased lymphocyte infiltration. While the increase in B7-H4 expression within the bladder by CD11b + monocytes is shared with human cancers, B7-H4 expression has not been previously identified in other murine cancer models. Higher expression of B7-H4 was associated with worse survival in muscle-invasive bladder cancer in humans, and increased B7-H4 expression was identified in luminal and luminal-papillary subtypes of bladder cancer. Evaluation of B7-H4 by single-cell RNA-Seq and immune mass cytometry of human bladder tumors found that B7-H4 is expressed in both the epithelium of urothelial carcinoma and CD68+ macrophages within the tumor. To investigate the function of B7-H4, treatment of human monocyte and T cell co-cultures with a B7-H4 blocking antibody resulted in enhanced IFN-γ secretion by CD4 + and CD8 + T cells. Additionally, anti-B7-H4 antibody treatment of BBNcarcinogen bladder cancers resulted in decreased tumor size, increased CD8 + T cell infiltration within the bladder, and a complimentary decrease in tumor-infiltrating T regulatory cells (Tregs). Furthermore, treatment with a combination of anti-PD-1 and anti-B7-H4 antibodies resulted in a significant reduction in tumor stage, a reduction in tumor size, and an increased level of tumor necrosis. These findings suggest that antibodies targeting B7-H4 may be a viable strategy for bladder cancers unresponsive to PD-1 checkpoint inhibitors.

Recent studies have shown significantly increased expression of matrix metalloproteinases (MMP) and disintegrin-type metalloproteinases (ADAM) during allograft rejection. In this regard, our previous studies have demonstrated contrasting roles for MMP-2 and MMP-9 during allograft rejection: MMP-2-deficiency enhanced allograft survival while MMP-9-deficiency decreased allograft survival. The aim of this study was to determine the effect of broad-spectrum MMP/ADAM inhibition on the pathogenesis of allograft rejection. Toward this, heterotopic BALB/c cardiac allografts were transplanted into C57BL/6 recipients treated with MMP/ADAM inhibitors, GM6001 or doxycycline. Systemic MMP/ADAM inhibition significantly enhanced allograft survival. Functioning allografts recovered from MMP/ADAM inhibitor-treated recipients showed lower cellular infiltration and tissue remodeling than rejected allografts recovered from control recipients. In addition, decreased chemotaxis of CD4+ and CD8+ T cells, B cells and macrophages was observed in vitro in the presence of MMP/ADAM inhibitors. Enhanced T-cell alloreactivity was also observed ex vivo in MMP/ADAM inhibitor-treated recipients and in vitro in the presence of MMP/ADAM inhibitors. These observations were associated with enhanced cytokine, chemokine and growth factor production. These results indicate that MMPs and ADAMs play a critical role in the pathogenesis of allograft rejection and may represent novel therapeutic targets for the treatment and/or prevention of this disease.

BackgroundExperimental autoimmune encephalomyelitis (EAE) is an animal model that captures many of the hallmarks of human multiple sclerosis (MS), including blood–brain barrier (BBB) breakdown, inflammation, demyelination and axonal destruction. The standard clinical score measurement of disease severity and progression assesses functional changes in animal mobility; however, it does not offer information regarding the underlying pathophysiology of the disease in real time. The purpose of this study was to apply a novel optical imaging technique that offers the advantage of rapid imaging of relevant biomarkers in live animals.MethodsAdvances in non-invasive fluorescence molecular tomographic (FMT) imaging, in combination with a variety of biological imaging agents, offer a unique, sensitive and quantifiable approach to assessing disease biology in living animals. Using vascular (AngioSense 750EX) and protease-activatable cathepsin B (Cat B 680 FAST) near infrared (NIR) fluorescence imaging agents to detect BBB breakdown and inflammation, respectively, we quantified brain and spinal cord changes in mice with relapsing-remitting PLP139-151-induced EAE and in response to tolerogenic therapy.ResultsFMT imaging and analysis techniques were carefully characterized and non-invasive imaging results corroborated by both ex vivo tissue imaging and comparison to clinical score results and histopathological analysis of CNS tissue. FMT imaging showed clear differences between control and diseased mice, and immune tolerance induction by antigen-coupled PLGA nanoparticles effectively blocked both disease induction and accumulation of imaging agents in the brain and spinal cord.ConclusionsCat B 680 FAST and AngioSense 750EX offered the combination best able to detect disease in both the brain and spinal cord, as well as the downregulation of disease by antigen-specific tolerance. Non-invasive optical tomographic imaging thus offers a unique approach to monitoring neuroinflammatory disease and therapeutic intervention in living mice with EAE.