Translational Immunotherapy

Publications

Year of publication 2018

Fernando P Canale, María C Ramello, Nicolás Núñez, Sabrina N Bossio, Eliane Piaggio, Adriana Gruppi, Eva V Acosta Rodríguez, Carolina L Montes (2018 Aug 18)

CD39 Expression Defines Cell Exhaustion in Tumor-Infiltrating CD8 T Cells-Response.

Cancer research : 5175 : DOI : 10.1158/0008-5472.CAN-18-0950 Learn more
Summary

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Year of publication 2017

Fernando P Canale, Maria C Ramello, Nicolas Núñez, Cintia L Araujo Furlan, Sabrina N Bossio, Melisa Gorosito Serrán, Jimena Tosello Boari, Andrés Del Castillo, Marta Ledesma, Christine Sedlik, Eliane Piaggio, Adriana Gruppi, Eva V Acosta Rodríguez, Carolina L Montes (2017 Oct 26)

CD39 expression defines cell exhaustion in tumor-infiltrating CD8+ T cells.

Cancer research : DOI : canres.2684.2016 Learn more
Summary

The ability of CD8+ T lymphocytes to eliminate tumors is limited by their ability to engender an immunosuppressive microenvironment. Here we describe a subset of tumor-infiltrating CD8+ T cells marked by high expression of the immunosuppressive ATP ecto-nucleotidase CD39. The frequency of CD39highCD8+ T cells increased with tumor growth but was absent in lymphoid organs. Tumor-infiltrating CD8+ T cells with high CD39 expression exhibited features of exhaustion, such as reduced production of TNF and IL-2 and expression of co-inhibitory receptors. Exhausted CD39+CD8+ T cells from mice hydrolyzed extracellular ATP, confirming that CD39 is enzymatically active. Furthermore, exhausted CD39+CD8+ T cells inhibited IFNγ production by responder CD8+ T cells. In specimens from breast cancer and melanoma patients, CD39+CD8+ T cells were present within tumors and invaded or metastatic lymph nodes, but were barely detectable within non-invaded lymph nodes and absent in peripheral blood. These cells exhibited an exhausted phenotype with impaired production of IFNγ, TNF, IL-2 and high expression of co-inhibitory receptors. Although T cell receptor engagement was sufficient to induce CD39 on human CD8+ T cells, exposure to IL-6 and IL-27 promoted CD39 expression on stimulated CD8+ T cells from human or murine sources. Our findings show how the tumor microenvironment drives the acquisition of CD39 as an immune regulatory molecule on CD8+ T cells, with implications for defining a biomarker of T cell dysfunction and a target for immunotherapeutic intervention.

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Alice Barbarin, Emilie Cayssials, Florence Jacomet, Nicolas Gonzalo Nunez, Sara Basbous, Lucie Lefèvre, Myriam Abdallah, Nathalie Piccirilli, Benjamin Morin, Vincent Lavoue, Véronique Catros, Eliane Piaggio, André Herbelin, Jean-Marc Gombert (2017 Apr 12)

Phenotype of NK-Like CD8(+) T Cells with Innate Features in Humans and Their Relevance in Cancer Diseases.

Frontiers in immunology : 316 : DOI : 10.3389/fimmu.2017.00316 Learn more
Summary

Unconventional T cells are defined by their capacity to respond to signals other than the well-known complex of peptides and major histocompatibility complex proteins. Among the burgeoning family of unconventional T cells, innate-like CD8(+) T cells in the mouse were discovered in the early 2000s. This subset of CD8(+) T cells bears a memory phenotype without having encountered a foreign antigen and can respond to innate-like IL-12 + IL-18 stimulation. Although the concept of innate memory CD8(+) T cells is now well established in mice, whether an equivalent memory NK-like T-cell population exists in humans remains under debate. We recently reported that CD8(+) T cells responding to innate-like IL-12 + IL-18 stimulation and co-expressing the transcription factor Eomesodermin (Eomes) and KIR/NKG2A membrane receptors with a memory/EMRA phenotype may represent a new, functionally distinct innate T cell subset in humans. In this review, after a summary on the known innate CD8(+) T-cell features in the mouse, we propose Eomes together with KIR/NKG2A and CD49d as a signature to standardize the identification of this innate CD8(+) T-cell subset in humans. Next, we discuss IL-4 and IL-15 involvement in the generation of innate CD8(+) T cells and particularly its possible dependency on the promyelocytic leukemia zinc-finger factor expressing iNKT cells, an innate T cell subset well documented for its susceptibility to tumor immune subversion. After that, focusing on cancer diseases, we provide new insights into the potential role of these innate CD8(+) T cells in a physiopathological context in humans. Based on empirical data obtained in cases of chronic myeloid leukemia, a myeloproliferative syndrome controlled by the immune system, and in solid tumors, we observe both the possible contribution of innate CD8(+) T cells to cancer disease control and their susceptibility to tumor immune subversion. Finally, we note that during tumor progression, innate CD8(+) T lymphocytes could be controlled by immune checkpoints. This study significantly contributes to understanding of the role of NK-like CD8(+) T cells and raises the question of the possible involvement of an iNKT/innate CD8(+) T cell axis in cancer.

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Thomas Simon, Julien Pogu, Séverine Rémy, Frédéric Brau, Sylvie Pogu, Maud Maquigneau, Jean-François Fonteneau, Nicolas Poirier, Bernard Vanhove, Gilles Blancho, Eliane Piaggio, Ignacio Anegon, Philippe Blancou (2017 Mar 27)

Inhibition of effector antigen-specific T cells by intradermal administration of heme oxygenase-1 inducers.

Journal of autoimmunity : 44-55 : DOI : S0896-8411(16)30389-4 Learn more
Summary

Developing protocols aimed at inhibiting effector T cells would be key for the treatment of T cell-dependent autoimmune diseases including type 1 autoimmune diabetes (T1D) and multiple sclerosis (MS). While heme oxygenase-1 (HO-1) inducers are clinically approved drugs for non-immune-related diseases, they do have immunosuppressive properties when administered systemically in rodents. Here we show that HO-1 inducers inhibit antigen-specific effector T cells when injected intradermally together with the T cell cognate antigens in mice. This phenomenon was observed in both a CD8(+) T cell-mediated model of T1D and in a CD4(+) T cell-dependent MS model. Intradermal injection of HO-1 inducers induced the recruitment of HO-1(+) monocyte-derived dendritic cell (MoDCs) exclusively to the lymph nodes (LN) draining the site of intradermal injection. After encountering HO-1(+)MoDCs, effector T-cells exhibited a lower velocity and a reduced ability to migrate towards chemokine gradients resulting in impaired accumulation to the inflamed organ. Intradermal co-injection of a clinically approved HO-1 inducer and a specific antigen to non-human primates also induced HO-1(+) MoDCs to accumulate in dermal draining LN and to suppress delayed-type hypersensitivity. Therefore, in both mice and non-human primates, HO-1 inducers delivered locally inhibited effector T-cells in an antigen-specific manner, paving the way for repositioning these drugs for the treatment of immune-mediated diseases.

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Rodrigo N Ramos, Eliane Piaggio, Emanuela Romano (2017 Mar 19)

Mechanisms of Resistance to Immune Checkpoint Antibodies.

Handbook of experimental pharmacology : DOI : 10.1007/164_2017_11 Learn more
Summary

Immunotherapy using checkpoint inhibitors has changed the way we treat several aggressive cancers such as melanoma, non-small cell lung and head & neck cancers, among others, with durable responses achieved in the metastatic setting. However, unfortunately, the vast majority of patients do not respond to checkpoint inhibition therapy and a minority of patients, who do respond to treatment, develop secondary resistance and experience relapse by mechanisms still inadequately understood. Emerging evidence shows that alterations in multiple signaling pathways are involved in primary and/or secondary resistance to checkpoint inhibition. In this review we discuss how selected cancer-cell autonomous cues may influence the outcome of cancer immunotherapy, particularly immune checkpoint inhibition.

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Year of publication 2016

Louis Pérol, John M Lindner, Pamela Caudana, Nicolas Gonzalo Nunez, Audrey Baeyens, Andrea Valle, Christine Sedlik, Delphine Loirat, Olivier Boyer, Alain Créange, José Laurent Cohen, Ute Christine Rogner, Jun Yamanouchi, Martine Marchant, Xavier Charles Leber, Meike Scharenberg, Marie-Claude Gagnerault, Roberto Mallone, Manuela Battaglia, Pere Santamaria, Agnès Hartemann, Elisabetta Traggiai, Eliane Piaggio (2016 Oct 7)

Loss of immune tolerance to IL-2 in type 1 diabetes.

Nature communications : 13027 : DOI : 10.1038/ncomms13027 Learn more
Summary

Type 1 diabetes (T1D) is characterized by a chronic, progressive autoimmune attack against pancreas-specific antigens, effecting the destruction of insulin-producing β-cells. Here we show interleukin-2 (IL-2) is a non-pancreatic autoimmune target in T1D. Anti-IL-2 autoantibodies, as well as T cells specific for a single orthologous epitope of IL-2, are present in the peripheral blood of non-obese diabetic (NOD) mice and patients with T1D. In NOD mice, the generation of anti-IL-2 autoantibodies is genetically determined and their titre increases with age and disease onset. In T1D patients, circulating IgG memory B cells specific for IL-2 or insulin are present at similar frequencies. Anti-IL-2 autoantibodies cloned from T1D patients demonstrate clonality, a high degree of somatic hypermutation and nanomolar affinities, indicating a germinal centre origin and underscoring the synergy between cognate autoreactive T and B cells leading to defective immune tolerance.

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Christine Sedlik, Adèle Heitzmann, Sophie Viel, Rafik Ait Sarkouh, Cornélie Batisse, Frédéric Schmidt, Philippe De La Rochere, Nathalie Amzallag, Eduardo Osinaga, Pablo Oppezzo, Otto Pritsch, Xavier Sastre-Garau, Pascale Hubert, Sebastian Amigorena, Eliane Piaggio (2016 Sep 14)

Effective antitumor therapy based on a novel antibody-drug conjugate targeting the Tn carbohydrate antigen.

Oncoimmunology : e1171434 : DOI : 10.1080/2162402X.2016.1171434 Learn more
Summary

Antibody-drug conjugates (ADC), combining the specificity of tumor recognition by monoclonal antibodies (mAb) and the powerful cytotoxicity of anticancer drugs, are currently under growing interest and development. Here, we studied the potential of Chi-Tn, a mAb directed to a glyco-peptidic tumor-associated antigen, to be used as an ADC for cancer treatment. First, we demonstrated that Chi-Tn specifically targeted tumor cells in vivo. Also, using flow cytometry and deconvolution microscopy, we showed that the Chi-Tn mAb is rapidly internalized – condition necessary to ensure the delivery of conjugated cytotoxic drugs in an active form, and targeted to early and recycling endosomes. When conjugated to saporin (SAP) or to auristatin F, the Chi-Tn ADC exhibited effective cytotoxicity to Tn-positive tumor cells in vitro, which correlated with the level of tumoral Tn expression. Furthermore, the Chi-Tn mAb conjugated to auristatin F also exhibited efficient antitumor activity in vivo, validating for the first time the use of an anti-Tn antibody as an effective ADC.

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Jérémie D Goldstein, Aude Burlion, Bruno Zaragoza, Kélhia Sendeyo, Julia K Polansky, Jochen Huehn, Eliane Piaggio, Benoit L Salomon, Gilles Marodon (2016 Apr 15)

Inhibition of the JAK/STAT Signaling Pathway in Regulatory T Cells Reveals a Very Dynamic Regulation of Foxp3 Expression.

PloS one : e0153682 : DOI : 10.1371/journal.pone.0153682 Learn more
Summary

The IL-2/JAK3/STAT-5 signaling pathway is involved on the initiation and maintenance of the transcription factor Foxp3 in regulatory T cells (Treg) and has been associated with demethylation of the intronic Conserved Non Coding Sequence-2 (CNS2). However, the role of the JAK/STAT pathway in controlling Foxp3 in the short term has been poorly investigated. Using two different JAK/STAT pharmacological inhibitors, we observed a detectable loss of Foxp3 after 10 min. of treatment that affected 70% of the cells after one hour. Using cycloheximide, a general inhibitor of mRNA translation, we determined that Foxp3, but not CD25, has a high turnover in IL-2 stimulated Treg. This reduction was correlated with a rapid reduction of Foxp3 mRNA. This loss of Foxp3 was associated with a loss in STAT-5 binding to the CNS2, which however remains demethylated. Consequently, Foxp3 expression returns to normal level upon restoration of basal JAK/STAT signaling in vivo. Reduced expression of several genes defining Treg identity was also observed upon treatment. Thus, our results demonstrate that Foxp3 has a rapid turn over in Treg partly controlled at the transcriptional level by the JAK/STAT pathway.

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Cira Dansokho, Dylla Ait Ahmed, Saba Aid, Cécile Toly-Ndour, Thomas Chaigneau, Vanessa Calle, Nicolas Cagnard, Martin Holzenberger, Eliane Piaggio, Pierre Aucouturier, Guillaume Dorothée (2016 Feb 26)

Regulatory T cells delay disease progression in Alzheimer-like pathology.

Brain : a journal of neurology : 1237-51 : DOI : 10.1093/brain/awv408 Learn more
Summary

Recent studies highlight the implication of innate and adaptive immunity in the pathophysiology of Alzheimer’s disease, and foster immunotherapy as a promising strategy for its treatment. Vaccines targeting amyloid-β peptide provided encouraging results in mouse models, but severe side effects attributed to T cell responses in the first clinical trial AN1792 underlined the need for better understanding adaptive immunity in Alzheimer’s disease. We previously showed that regulatory T cells critically control amyloid-β-specific CD4(+) T cell responses in both physiological and pathological settings. Here, we analysed the impact of regulatory T cells on spontaneous disease progression in a murine model of Alzheimer’s disease. Early transient depletion of regulatory T cells accelerated the onset of cognitive deficits in APPPS1 mice, without altering amyloid-β deposition. Earlier cognitive impairment correlated with reduced recruitment of microglia towards amyloid deposits and altered disease-related gene expression profile. Conversely, amplification of regulatory T cells through peripheral low-dose IL-2 treatment increased numbers of plaque-associated microglia, and restored cognitive functions in APPPS1 mice. These data suggest that regulatory T cells play a beneficial role in the pathophysiology of Alzheimer’s disease, by slowing disease progression and modulating microglial response to amyloid-β deposition. Our study highlights the therapeutic potential of repurposed IL-2 for innovative immunotherapy based on modulation of regulatory T cells in Alzheimer’s disease.

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Year of publication 2015

Louis Pérol, Eliane Piaggio (2015 Nov 5)

New Molecular and Cellular Mechanisms of Tolerance: Tolerogenic Actions of IL-2.

Methods in molecular biology (Clifton, N.J.) : 11-28 : DOI : 10.1007/978-1-4939-3139-2_2 Learn more
Summary

Interleukin-2 (IL-2) is an old molecule with brand new functions. Indeed, IL-2 has been first described as a T-cell growth factor but recent data pointed out that its main function in vivo is the maintenance of immune tolerance. Mechanistically, IL-2 is essential for the development and function of CD4(+) Foxp3(+) regulatory T cells (Treg cells) that are essential players in the control of immune responded to self, tumors, microbes and grafts. Treg cells are exquisitely sensitive to IL-2 due to their constitutive expression of the high affinity IL-2 receptor (IL-2R) and the new paradigm suggests that low-doses of IL-2 could selectively boost Treg cells in vivo. Consequently, a growing body of clinical research is aiming at using IL-2 at low doses as a tolerogenic drug to boost endogenous Treg cells in patients suffering from autoimmune or inflammatory conditions. In this manuscript, we briefly review IL-2/IL-2R biology and the role of IL-2 in the development, maintenance, and function of Treg cells; and also its effects on other immune cell populations such as CD4(+) T helper cells and CD8(+) memory T cells. Then, focusing on type 1 diabetes, we review the preclinical studies and clinical trials supporting the use of low-doses IL-2 as a tolerogenic immunotherapy. Finally, we discuss the limitations and future directions for IL-2 based immunotherapy.

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R Elhage, M Cheraï, B Levacher, G Darrasse-Jeze, C Baillou, X Zhao, A-M Khatib, E Piaggio, D Klatzmann (2015 Feb 17)

C-terminal cleavage of human Foxp3 at a proprotein convertase motif abrogates its suppressive function.

Scandinavian journal of immunology : 229-39 : DOI : 10.1111/sji.12275 Learn more
Summary

Foxp3 plays a critical role in the development and function of regulatory T cells (Tregs). Differences in translational and post-translational processing of murine and human Foxp3 have been recently reported. Human Foxp3 exists as four isoforms generated by alternative splicing. Mouse Foxp3 only exists as one isoform, but can be proteolytically cleaved by N-terminal and/or C-terminal proprotein convertase subtilisin/kexins (PCSKs). Here, we show by transcriptome analysis that the proprotein convertases PCSK7, PCSK5 and Furin are present in human CD4(+) T cells with different expression patterns. Notably, after in vitro activation, only PCSK7 and Furin are expressed in Tregs and T effector cells (Teffs), with overexpression of PCSK7 in Tregs compared to Teffs. Human Foxp3 protein displays specific motifs that can be potentially cleaved by convertases. Consequently, we transduced human CD4(+) cells with Foxp3-expressing lentiviral vectors and assessed the generation of proteolytically cleaved Foxp3 forms by Western blot. Three different Foxp3 forms were detected, indicating that human Foxp3 can also be subjected to proteolytic cleavage at the N-terminal and C-terminal ends. These results prompted us to assess the suppressive activity associated with each forms. We observed that full length and N-cleaved Foxp3-transduced CD4(+) T cells similarly suppressed the in vitro proliferation of Teffs. However, the C-cleaved or N&C-cleaved Foxp3 forms afforded almost no suppressive function, indicating a crucial role of the human Foxp3 C-terminal region in Tregs suppressive activity, in marked contrast with the report of a superior suppressive activity for the C-cleaved murine Foxp3 compared to the full length.

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Andrea Valle, Giulia Barbagiovanni, Tatiana Jofra, Angela Stabilini, Louis Perol, Audrey Baeyens, Santosh Anand, Nicolas Cagnard, Nicola Gagliani, Eliane Piaggio, Manuela Battaglia (2015 Feb 2)

Heterogeneous CD3 expression levels in differing T cell subsets correlate with the in vivo anti-CD3-mediated T cell modulation.

Journal of immunology (Baltimore, Md. : 1950) : 2117-27 : DOI : 10.4049/jimmunol.1401551 Learn more
Summary

The tolerogenic anti-CD3ε monoclonal Abs (anti-CD3) are promising compounds for the treatment of type 1 diabetes. Anti-CD3 administration induces transient T cell depletion both in preclinical and in clinical studies. Notably, the said depletion mainly affects CD4(+) but not CD8(+) T cells. Moreover, type 1 diabetes reversal in preclinical models is accompanied by the selective expansion of CD4(+)Foxp3(+) T regulatory (Treg) cells, which are fundamental for the long-term maintenance of anti-CD3-mediated tolerance. The mechanisms that lead to this immune-shaping by affecting mainly CD4(+) T effector cells while sparing CD4(+)Foxp3(+) Treg cells have still to be fully elucidated. This study shows that CD3 expression levels differ from one T cell subset to another. CD4(+)Foxp3(-) T cells contain higher amounts of CD3 molecules than do CD4(+)Foxp3(+) and CD8(+) T cells in both mice and humans. The said differences correlate with the anti-CD3-mediated immune resetting that occurs in vivo after anti-CD3 administration in diabetic NOD mice. Additionally, transcriptome analysis demonstrates that CD4(+)Foxp3(+) Treg cells are significantly less responsive than are CD4(+)Foxp3(-) T cells to anti-CD3 treatment at a molecular level. Thus, heterogeneity in CD3 expression seems to confer to the various T cell subsets differing susceptibility to the in vivo tolerogenic anti-CD3-mediated modulation. These data shed new light on the molecular mechanism that underlies anti-CD3-mediated immune resetting and thus may open new opportunities to improve this promising treatment.

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Year of publication 2014

Audrey Baeyens, David Saadoun, Fabienne Billiard, Angéline Rouers, Sylvie Grégoire, Bruno Zaragoza, Yenkel Grinberg-Bleyer, Gilles Marodon, Eliane Piaggio, Benoît L Salomon (2014 Dec 31)

Effector T cells boost regulatory T cell expansion by IL-2, TNF, OX40, and plasmacytoid dendritic cells depending on the immune context.

Journal of immunology (Baltimore, Md. : 1950) : 999-1010 : DOI : 10.4049/jimmunol.1400504 Learn more
Summary

CD4(+)CD25(+)Foxp3(+) regulatory T (Treg) cells play a major role in peripheral tolerance. Multiple environmental factors and cell types affect their biology. Among them, activated effector CD4(+) T cells can boost Treg cell expansion through TNF or IL-2. In this study, we further characterized this effector T (Teff) cell-dependent Treg cell boost in vivo in mice. This phenomenon was observed when both Treg and Teff cells were activated by their cognate Ag, with the latter being the same or different. Also, when Treg cells highly proliferated on their own, there was no additional Treg cell boost by Teff cells. In a condition of low inflammation, the Teff cell-mediated Treg cell boost involved TNF, OX40L, and plasmacytoid dendritic cells, whereas in a condition of high inflammation, it involved TNF and IL-2. Thus, this feedback mechanism in which Treg cells are highly activated by their Teff cell counterparts depends on the immune context for its effectiveness and mechanism. This Teff cell-dependent Treg cell boost may be crucial to limit inflammatory and autoimmune responses.

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Florencia B González, Silvina R Villar, Rodrigo Fernández Bussy, Gaëlle H Martin, Louis Pérol, Romina Manarin, Silvana V Spinelli, Caroline Pilon, José Laurent Cohen, Oscar A Bottasso, Eliane Piaggio, Ana R Pérez (2014 Dec 9)

Immunoendocrine dysbalance during uncontrolled T. cruzi infection is associated with the acquisition of a Th-1-like phenotype by Foxp3(+) T cells.

Brain, behavior, and immunity : 219-32 : DOI : 10.1016/j.bbi.2014.11.016 Learn more
Summary

We previously showed that Trypanosomacruzi infection in C57BL/6 mice results in a lethal infection linked to unbalanced pro- and anti-inflammatory mediators production. Here, we examined the dynamics of CD4(+)Foxp3(+) regulatory T (Treg) cells within this inflammatory and highly Th1-polarized environment. Treg cells showed a reduced proliferation rate and their frequency is progressively reduced along infection compared to effector T (Teff) cells. Also, a higher fraction of Treg cells showed a naïve phenotype, meanwhile Teff cells were mostly of the effector memory type. T. cruzi infection was associated with the production of pro- and anti-inflammatory cytokines, notably IL-27p28, and with the induction of T-bet and IFN-γ expression in Treg cells. Furthermore, endogenous glucocorticoids released in response to T. cruzi-driven immune activation were crucial to sustain the Treg/Teff cell balance. Notably, IL-2 plus dexamethasone combined treatment before infection was associated with increased Treg cell proliferation and expression of GATA-3, IL-4 and IL-10, and increased mice survival time. Overall, our results indicate that therapies aimed at specifically boosting Treg cells, which during T. cruzi infection are overwhelmed by the effector immune response, represent new opportunities for the treatment of Chagas disease, which is actually only based on parasite-targeted chemotherapy.

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C B Pilon, S Petillon, S Naserian, G H Martin, C Badoual, P Lang, D Azoulay, E Piaggio, P Grimbert, J L Cohen (2014 Nov 15)

Administration of low doses of IL-2 combined to rapamycin promotes allogeneic skin graft survival in mice.

American journal of transplantation : official journal of the American Society of Transplantation and the American Society of Transplant Surgeons : 2874-82 : DOI : 10.1111/ajt.12944 Learn more
Summary

Human CD4(+) CD25(+) FoxP3(+) regulatory T cells (Tregs) prevent allogeneic graft rejection by inhibiting T cell activation, as has been shown in mouse models. Recently, low-dose IL-2 administration was shown to specifically activate Tregs but not pathogenic conventional T cells, leading to resolution of type 1 diabetes in nonobese diabetic mice. We therefore tested the ability of low-dose IL-2 to prevent allogeneic skin graft rejection. We found that while IL-2 alone was inefficient in preventing rejection, combined with rapamycin, IL-2 treatment promoted skin graft survival both in minor disparate and semi-allogeneic skin graft combinations. Tregs are activated by this combined treatment while conventional CD4(+) cell expansion and activation are markedly inhibited. Co-administration of anti-CD25 antibodies dramatically reduces the effect of the IL-2/rapamycin treatment, strongly supporting a central role for Treg activation. Thus, we provide the first preclinical data showing that low-dose IL-2 combined with rapamycin can significantly delay transplant rejection in mice. These findings may form the rational for clinical evaluation of this novel approach for the prevention of transplant rejection.

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