Abstract: Isolated MHC-derived human peptides, particularly an isolated MHC-derived human peptide including a SDVGE-X-R (SEQ ID NO: 13) 7 amino acids motif that is selected from: NQEESVRFDSDVGEFR (Hpep 1-SEQ ID NO:1), NREEYARFDSDVGEFR (Hpep2-SEQ ID NO:2), NREEYVRFDSDVGEYR (Hpep4-SEQ ID NO:4) and any peptide with a length of 16 amino acids including the SDVGE-X-R (SEQ ID NO: 13) motif and having an amino acid sequence with at least 80, 85, 86, 87, 88, 90, 91, 92, 93, 94, 95, 96, 97, 98 or 99% identity with SEQ ID NO: 1, SEQ ID NO: 2 or SEQ ID NO: 4. Also, the use of these peptides in methods for inducing an immune tolerance, for preventing or reducing transplant rejection or graft versus host disease (GVHD), and in methods for isolating and expanding a population of CD8+CD45RClow Tregs or for expanding a population of CD8+CD45RClow Tregs and stimulating its immunosuppressive activity.

Abstract: The invention relates to an isolated interleukin-34 (IL-34) polypeptide for use in preventing or treating graft rejection, autoimmune disease, unwanted immune response against therapeutic proteins and allergy. The invention also provides an in vitro method for determining whether a patient is at risk of transplant rejection, autoimmune diseases, unwanted immune response against therapeutic proteins or allergies, comprising a step of determining the expression level of IL-34 in a biological sample obtained from said patient, wherein the presence of IL-34 is indicative of a reduced risk of transplant rejection, autoimmune diseases, unwanted immune response against therapeutic proteins or allergies.

Abstract: The invention relates to an isolated interleukin-34 (IL-34) polypeptide for use in preventing or treating graft rejection, autoimmune disease, unwanted immune response against therapeutic proteins and allergy. The invention also provides an in vitro method for determining whether a patient is at risk of transplant rejection, autoimmune diseases, unwanted immune response against therapeutic proteins or allergies, comprising a step of determining the expression level of IL-34 in a biological sample obtained from said patient, wherein the presence of IL-34 is indicative of a reduced risk of transplant rejection, autoimmune diseases, unwanted immune response against therapeutic proteins or allergies.

Abstract: A population of highly suppressive human CD8+CD45RClow/? Tregs is characterized by expressing Foxp3 and producing IFN?, IL-10, IL-34 and TGF? to mediate their suppressive activity. Accordingly, methods capable of increasing expansion and immunosuppressive capacity of such a population of CD8+CD45RClow/? Tregs are highly desirable for therapeutic purposes. Rapamycin has been shown to increase the expansion and immunosuppressive capacities of the population of CD8+CD45RClow/? Tregs. Accordingly, the method of increasing expansion and immunosuppressive capacity of a population of CD8+CD45RClow/? Tregs includes culturing the population of CD8+CD45RClow/? Tregs in presence of a rapamycin compound.

Abstract: The present invention relates to methods for detecting, assessing severity and treating multiple sclerosis. The inventors showed an impairment of the function of CD8+ Treg cells in MS patients and they demonstrated here that several criteria correlated with the disease severity i.e. the percentage of CD8+CD45RCintCD161lowValpha7? T cells in the blood, the secretion of IFNg and IL10 and the suppressive activity of the CD8+CD45RCintCD161lowValpha7? T cells. In particular, the present invention relates to a method for determining whether a subject has or is at risk of having multiple sclerosis comprising i) determining the percentage of CD8+CD45RCintCD161lowValpha7? T cells in a biological sample obtained from the subject, ii) comparing the percentage determined at step i) with a predetermined reference value and iii) detecting differential in the percentage determined at step i) with the predetermined reference value indicates that the subject has or is at risk of having multiple sclerosis.

Abstract: Disclosed is a method for obtaining a population of human Treg cells including the steps of: (a) culturing a population of human monocytes with a medium including an amount of an interleukin-34 (IL-34) polypeptide in order to obtain a population of immunosuppressive macrophages; (b) co-culturing a population of human peripheral blood mononuclear cells (PBMCs) and the population of immunosuppressive macrophages obtained at step (a).

Abstract: Disclosed is a method for obtaining a population of human Treg cells including the steps of: (a) culturing a population of human monocytes with a medium including an amount of an interleukin-34 (IL-34) polypeptide in order to obtain a population of immunosuppressive macrophages; (b) co-culturing a population of human peripheral blood mononuclear cells (PBMCs) and the population of immunosuppressive macrophages obtained at step (a).

Abstract: Disclosed is a method for labeling, detecting and/or isolating Foxp3+ Treg cells from a biological sample containing peripheral blood mononuclear cells (PBMC) or lymphocytes including the following steps of: (i) coupling the surface of PBMC or lymphocytes to a capture moiety which binds to the cell through a cell surface molecule and to interleukin-34 (IL34), (ii) culturing the lymphocytes under conditions wherein IL34 is secreted, released and specifically captured by the capture moiety, (iii) labeling the IL34 expressing lymphocytes with a label moiety, and (iv) optionally detecting and/or isolating the IL34 expressing lymphocytes which are Foxp3+ Treg cells. Also disclosed is an isolated population of Foxp3+ Treg cells obtainable by the method and uses thereof.

Abstract: The invention relates to an isolated interleukin-34 (IL-34) polypeptide for use in preventing or treating graft rejection, autoimmune disease, unwanted immune response against therapeutic proteins and allergy. The invention also provides an in vitro method for determining whether a patient is at risk of transplant rejection, autoimmune diseases, unwanted immune response against therapeutic proteins or allergies, comprising a step of determining the expression level of IL-34 in a biological sample obtained from said patient, wherein the presence of IL-34 is indicative of a reduced risk of transplant rejection, autoimmune diseases, unwanted immune response against therapeutic proteins or allergies.

Abstract: Disclosed is a new subpopulation of CD8+CD45RClow Tregs, namely IFN?+IL-10+IL-34+ secreting population of CD8+CD45RClow Treg cells, methods for their isolation and expansion and their use as drug, more particularly for immunotherapy as well as biomarker

Abstract: Disclosed is a method for obtaining a population of human Treg cells including the steps of: (a) culturing a population of human monocytes with a medium including an amount of an interleukin-34 (IL-34) polypeptide in order to obtain a population of immunosuppressive macrophages; (b) co-culturing a population of human peripheral blood mononuclear cells (PBMCs) and the population of immunosuppressive macrophages obtained at step (a).

Abstract: Disclosed is a method for labeling, detecting and/or isolating Foxp3+ Treg cells from a biological sample containing peripheral blood mononuclear cells (PBMC) or lymphocytes including the following steps of: (i) coupling the surface of PBMC or lymphocytes to a capture moiety which binds to the cell through a cell surface molecule and to interleukin-34 (IL34), (ii) culturing the lymphocytes under conditions wherein IL34 is secreted, released and specifically captured by the capture moiety, (iii) labeling the IL34 expressing lymphocytes with a label moiety, and (iv) optionally detecting and/or isolating the IL34 expressing lymphocytes which are Foxp3+ Treg cells. Also disclosed is an isolated population of Foxp3+ Treg cells obtainable by the method and uses thereof.