Major limitations of currently investigated␣␤T cells redirected against cancer by transfer of tumor-specific ␣␤TCR arise from their low affinity, MHC restriction, and risk to mediate self-reactivity after pairing with endogenous ␣ or ␤TCR chains. Therefore, the ability of a defined ␥9␦2TCR to redirect ␣␤T cells selectively against tumor cells was tested and its molecular interaction with a variety of targets investigated. Functional analysis revealed that a ␥9␦2TCR efficiently reprograms both CD4 ؉ and CD8 ؉ IntroductionThe major challenge in the field of adoptive immunotherapy is the generation of tumor-reactive ␣␤T cells which can be applied to a broad variety of cancer patients. To facilitate the rapid generation of tumor-reactive ␣␤T cells, it has been proposed that ␣␤T cells can be reprogrammed with genes encoding for a tumor-specific ␣␤TCR or a chimeric receptor. 1 Several such receptors are already being used to redirect ␣␤T cells in phase 1 clinical trials. 1,2 However, reprogramming ␣␤T cells with defined ␣␤TCRs is substantially hampered by their restriction to HLA types, thus limiting the number of patients who can be treated with one ␣␤TCR. In addition, pairing of introduced with endogenous ␣␤TCR chains can induce life-threatening autoreactivity. 3,4 One attractive alternative to mediate a selective antitumor reactivity with a high-affinity TCR might arise from the ability of ␥␦T cells to mediate antitumor reactivity while ignoring a healthy environment. [5][6][7] Isolated ␥9␦2T cells efficiently kill tumor cells of hematologic malignancies and from solid tumors. 7 However, the function and proliferation capacity of ␥␦T cells is frequently heavily impaired in cancer patients 8 making autologous ␥␦T cells less attractive for immune interventions. On the other hand, as end-stage cancer patients can easily elicit ␣␤T-cell immune responses against, for example, viral Ags, 9,10 ␣␤T cells might serve as carriers for broadly tumor-reactive ␥␦TCRs.The recognition of mevalonate metabolites (phosphoantigens) 11 which are overexpressed in a broad range of tumor cells has been suggested as an important mechanism by which multiple ␥9␦2TCR can sense malignant transformation as the recognition involves TCR domains which are conserved in most ␥9␦2TCRs. [12][13][14] In addition, ␥9␦2TCR G115 has been also suggested to bind to a complex of Apolipoprotein AI (ApoAI) and F1-ATPase, 15 a complex mitochondrial enzyme found on the surface of many malignant cells. 16 This knowledge might allow a rational design of ␥␦T cell-based immunotherapies. Therefore, we investigated whether a defined ␥9␦2TCR can be efficiently expressed in ␣␤T cells, mediate tumor-specific proliferation of ␣␤T cells, and redirect both effector CD8 ϩ and helper CD4 ϩ ␣␤T-cell subsets against a broad panel of tumor cell lines while ignoring normal cells in vitro and in vivo. MethodsCell lines, Abs, the retroviral transduction and expansion of ␣␤T cells, functional T-cell assays 11,[17][18][19][20] as well as the animal model used are described in supp...

BackgroundCSF-1 or IL-34 stimulation of CSF1R promotes macrophage differentiation, activation and osteoclastogenesis, and pharmacological inhibition of CSF1R is beneficial in animal models of arthritis. The objective of this study was to determine the relative contributions of CSF-1 and IL-34 signaling to CSF1R in RA.MethodsCSF-1 and IL-34 were detected by immunohistochemical and digital image analysis in synovial tissue from 15 biological-naïve rheumatoid arthritis (RA) , 15 psoriatic arthritis (PsA) and 7 osteoarthritis (OA) patients . Gene expression in CSF-1- and IL-34-differentiated human macrophages was assessed by FACS analysis and quantitative PCR. RA synovial explants were incubated with CSF-1, IL-34, control antibody (Ab), or neutralizing/blocking Abs targeting CSF-1, IL-34, or CSF1R. The effect of a CSF1R-blocking Ab was examined in murine collagen-induced arthritis (CIA).ResultsCSF-1 (also known as M-CSF) and IL-34 expression was similar in RA and PsA synovial tissue, but lower in controls (P < 0.05). CSF-1 expression was observed in the synovial sublining, and IL-34 in the sublining and the intimal lining layer. CSF-1 and IL-34 differentially regulated the expression of 17 of 336 inflammation-associated genes in macrophages, including chemokines, extra-cellular matrix components, and matrix metalloproteinases. Exogenous CSF-1 or IL-34, or their independent neutralization, had no effect on RA synovial explant IL-6 production. Anti-CSF1R Ab significantly reduced IL-6 and other inflammatory mediator production in RA synovial explants, and paw swelling and joint destruction in CIA.ConclusionsSimultaneous inhibition of CSF1R interactions with both CSF-1 and IL-34 suppresses inflammatory activation of RA synovial tissue and pathology in CIA, suggesting a novel therapeutic strategy for RA.Electronic supplementary materialThe online version of this article (doi:10.1186/s13075-016-0973-6) contains supplementary material, which is available to authorized users.

Angiopoietin (Ang) -1 and -2 and their receptor Tie2 play critical roles in regulating angiogenic processes during development, homeostasis, tumorigenesis, inflammation and tissue repair. Tie2 signaling is best characterized in endothelial cells, but a subset of human and murine circulating monocytes/macrophages essential to solid tumor formation express Tie2 and display immunosuppressive properties consistent with M2 macrophage polarization. However, we have recently shown that Tie2 is strongly activated in pro-inflammatory macrophages present in rheumatoid arthritis patient synovial tissue. Here we examined the relationship between Tie2 expression and function during human macrophage polarization. Tie2 expression was observed under all polarization conditions, but was highest in IFN-γ and IL-10 –differentiated macrophages. While TNF enhanced expression of a common restricted set of genes involved in angiogenesis and inflammation in GM-CSF, IFN-γ and IL-10 –differentiated macrophages, expression of multiple chemokines and cytokines, including CXCL3, CXCL5, CXCL8, IL6, and IL12B was further augmented in the presence of Ang-1 and Ang-2, via Tie2 activation of JAK/STAT signaling. Conditioned medium from macrophages stimulated with Ang-1 or Ang-2 in combination with TNF, sustained monocyte recruitment. Our findings suggest a general role for Tie2 in cooperatively promoting the inflammatory activation of macrophages, independently of polarization conditions.