Our laboratory investigates the genetic control mechanisms allowing the immune system to recognize and destroy foreign pathogens, but not normal constituents of the body. Defects in these mechanisms underlie many autoimmune diseases, including type 1 (juvenile onset, insulin dependent) diabetes. Using NOD (non-obese diabetic) inbred mice, we focus on the process through which genes that normally elicit immune responses to foreign intruders can sometimes trigger autoimmune responses against the body's own cells, such as the pancreatic cells that make insulin. We have shown that some genes play a role in type 1 diabetes even when they do not contain deleterious mutations. Instead they are normal genes that only contribute to type 1 diabetes pathology when collected together in a specific fashion. We are also investigating defects in the differentiation of a particular type of leukocyte in NOD mice that subsequently allows for the development of autoimmune responses. This work may help identify the mechanisms and compounds that normally prevent autoimmunity, and hence reveal strategies for pharmacological interventions in humans at risk for type 1 diabetes.
Genetic Basis of Immunological Tolerance Defects Underlying Type 1 Diabetes
Our primary research interest is understanding the genetic basis for immune tolerance to endogenous proteins. Defects in these mechanisms lead to many debilitating autoimmune diseases, of which type 1 diabetes (T1D) is one of the most serious. In both humans and NOD mice, T1D results when insulin-producing pancreatic ß-cells are destroyed by an autoreactive T-cell response. Thus, insights into the genetic mechanisms responsible for the normal maintenance of immunological tolerance can be gained by identifying the pathogenic basis of T1D in NOD mice.
T1D is controlled by a large number of susceptibility (Idd) genes. However, genes within particular major histocompatibility complexes (MHC) provide the primary component for T1D susceptibility in both humans and NOD mice. The MHC encodes two primary types of gene products, termed class I and class II. Class I molecules present peptides derived from intracellular proteins to CD8 T-cells, which usually exert cytotoxic functions. Virtually all cells express MHC class I molecules. In contrast, MHC class II expression is largely limited to a specialized subset of hematopoietically derived antigen presenting cells (APC) that include B-lymphocytes, macrophages, and dendritic cells (DC). MHC class II molecules expressed by APC display peptides derived from internalized extracellular proteins to CD4 T-cells, which produce cytokine molecules that amplify other components of the immune response, including cytotoxic CD8 T-cells.
T-cells specifically recognize a particular peptide/MHC antigenic complex through expression of clonally distributed T-cell receptor (TCR) molecules generated by somatically rearranged gene sequences. In addition to those derived from infectious pathogens, APC also display to T-cells MHC class I- and class II-bound peptides generated from endogenous "self" proteins. A normal consequence of expressing a TCR that engages "self antigenic" complexes on APC at a critically high threshold level is the induction of signals triggering the deletion or permanent inactivation of potentially autoreactive T-cells. Defects in this process of immunological tolerance induction manifested by both T-cells and APC underlie susceptibility to T1D.
In both humans and NOD mice, unusual MHC class II genes clearly contribute to T1D by inducing pathogenic CD4 T-cell responses. However, while representing common variants shared by many strains lacking autoimmune proclivity, the MHC class I molecules expressed by NOD mice also exert pathogenic functions essential to T1D development. These common class I variants aberrantly exert diabetogenic functions in NOD mice through interactions with some of this strain's multiple Idd genes located outside the MHC. The strongest such interactive effect is provided by a gene(s) within the Idd7 locus. The NOD Idd7 variant appears to prevent the TCR of autoreactive T-cells from being expressed at the level necessary to elicit a signaling response that is sufficiently strong to trigger the deletion of such pathogenic effectors upon their engagement of self antigen.
In humans, epidemiological studies also suggested that when co-expressed with particular combinations of other genes, some common MHC class I variants such as HLA-A2.1 could contribute to T1D development. To test this possibility, we generated NOD mice that transgenically express human HLA-A2.1, but no murine class I molecules. The human HLA-A2.1 molecules in these mice were found to mediate diabetogenic T-cell responses. Together with collaborators at The Albert Einstein College of Medicine, we identified three ß -cell autoantigenic peptides that are presented to diabetogenic T-cells by human HLA-A2.1 class I molecules in our transgenic mice. Subsequent work by another collaborator at Leiden University in The Netherlands revealed that at least one of these peptides is recognized in an HLA-A2.1-dependent fashion by CD8 T-cells isolated from a human T1D patient.
B-lymphocytes represent a critical subset of APC for activating the MHC class II-dependent T-cell responses contributing to T1D in NOD mice. The preferential ability of NOD B-lymphocytes to serve as diabetogenic APC results from the fact that they, unlike other types of APC, express plasma membrane-bound immunoglobulin (Ig) molecules which specifically capture and internalize ß -cell proteins. Mechanisms are normally in place to prevent the development of B-lymphocytes expressing autoreactive Ig molecules. We found that several of these mechanisms are defective in NOD mice. Further studies indicated that genes within the Idd5 and Idd9/11 loci contribute to the defective ability of NOD mice to inactivate B-lymphocytes expressing autoreactive Ig molecules.
The DC subset of APC in NOD mice is characterized by developmental defects preventing them from presenting self antigens in a sufficiently vigorous fashion to induce T-cell tolerogenic processes. Human T1D patients share similar DC developmental defects. Impaired DC differentiation in NOD mice is in turn linked to numerical deficiencies in the CD4-expressing subset of immunoregulatory natural killer (NK) T-cells that also characterize this strain. The loss of this NKT-cell subset appears to result from the fact that they are highly sensitive to apoptotic deletion when the cell surface enzyme ADP-ribosyltransferase 2 (ART2) is activated by its substrate NAD. Thus, blocking ART2 activity may have T1D protective effects in NOD mice by enhancing the survival of NKT-cells that in turn drive development of tolerogenic DC. However, due to its small size, and the fact that it is deeply imbedded in the plasma membrane, the catalytic site of ART2 cannot be targeted by conventional two-chain antibodies. However, llamas have the unusual feature of being able to generate single-chain antibodies that can target small, not readily accessible molecules. Early results from studies done in collaboration with investigators at the University of Hamburg in Germany indicate that treatment with a llama single-chain antibody can block ART2 activity in NOD mice resulting in enhanced numbers of NKT-cells and potentially tolerogenic DC. Further studies are ongoing to determine if blocking ART2 activity with this llama single-chain antibody has T1D protective effects in NOD mice.
Principal Investigator: David V. Serreze, Ph.D.
Postdoctoral Fellows: Maximiliano Fernando Presa, Ph.D., Jeremy Racine, Ph.D.
Research Lab Manager: Harold D. Chapman, B.S.
Research Assistant I: Jeremy Ratiu
Colony Coordinator: Brenice Timms
Manager, Type 1 Diabetes Repos: Racheal Wallace
Research Administrative Assistant: Norma D. Buckley
Garabatos N, Alvarez R, Carrillo J, Carrascal J, Izquierdo C, Chapman HD, Presa M, Mora C, Serreze DV, Verdaguer J, Stratmann T. 2014. In vivo detection of peripherin-specific autoreactive B cells during type 1 diabetes pathogenesis. Journal of immunology 192(7): 3080-3090. PMCID: PMC3994320.
Lamont D, Mukherjee G, Kumar PR, Samanta D, McPhee CG, Kay TW, Almo SC, DiLorenzo TP, Serreze DV. 2014. Compensatory mechanisms allow undersized anchor-deficient class I MHC ligands to mediate pathogenic autoreactive T cell responses. Journal of immunology 193(5): 2135-2146. PMCID: PMC4134999.
Presa M, Ortiz AZ, Garabatos N, Izquierdo C, Rivas EI, Teyton L, Mora C, Serreze D, Stratmann T. 2013. Cholera toxin subunit B-peptide fusion proteins reveal impaired oral tolerance induction in diabetes-prone but not in diabetes-resistant mice. Eur J Immunol 43(11): 2969-2979. PMCID: PMC3856580
Mukherjee G, Geliebter A, Babad J, Santamaria P, Serreze DV, Freeman GJ, Tarbell KV, Sharpe A, Dilorenzo TP. 2013. DEC-205-mediated antigen Targeting to steady-state dendritic cells induces deletion of diabetogenic CD8+ T cells independently of PD-1 and PD-L1. Int Immunol 25(11): 651-660. PMCID: PMC3806169
Lee JS, Scandiuzzi L, Ray A, Wei J, Hofmeyer KA, Abadi YM, Loke P, Lin J, Yuan J, Serreze DV, Allison JP, Zang X. 2012. B7x in the periphery abrogates pancreas-specific damage mediated by self-reactive CD8 T cells. J Immunol 189(8): 4165-4174. PMCID: PMC3466330
Stolp J, Chen YG, Cox SL, Henck V, Zhang W, Tsaih SW, Chapman H, Stearns T, Serreze DV, Silveira PA. 2012. Subcongenic analyses reveal complex interactions between distal chromosome 4 genes controlling diabetogenic B cells and CD4 T cells in nonobese diabetic mice. J Immunol 189(3): 1406-1417. PMCID: PMC3401322
Chen YG, Tsaih SW, Serreze DV. 2012. Genetic control of murine invariant natural killer T-cell development dynamically differs dependent on the examined tissue type. Genes Immun 13(2): 164-174. PMCID: PMC3291802
Wekerle H, Flugel A, Fugger L, Schett G, Serreze D. 2012. Autoimmunity's next top models. Nat Med 18(1): 66-70. Commentary
Unger WW, Pearson T, Abreu JR, Laban S, van der Slik AR, der Kracht SM, Kester MG, Serreze DV, Shultz LD, Griffioen M, Drijfhout JW, Greiner DL, Roep BO. 2012. Islet-specific CTL cloned from a Type 1 diabetes patient cause beta-cell destruction after engraftment into HLA-A2 transgenic NOD/SCID/IL2RG null mice. PLoS One 7(11): e49213. PMCID: PMC3498321
Bogdanik LP, Chapman HD, Miers KE, Serreze DV, Burgess RW. 2012. A MusD retrotransposon insertion in the mouse Slc6a5 gene causes alterations in neuromuscular junction maturation and behavioral phenotypes. PLoS One 7(1): e30217. PMCID: PMC3260239
Chen YG, Scheuplein F, Driver JP, Hewes AA, Reifsnyder PC, Leiter EH, Serreze DV. 2011. Testing the role of P2X(7) receptors in the development of type 1 diabetes in nonobese diabetic mice. J Immunol 186:4278-4284. PMCID: PMC3094905
Driver JP, Chen YG, Zhang W, Asrat S, Serreze DV. 2011. Unmasking genes in a type 1 diabetes-resistant mouse strain that enhances pathogenic CD8 T-cell responses. Diabetes 60:1354-1359. PMCID: PMC3064110
Driver JP, Lamont DJ, Gysemans C, Mathieu C, Serreze DV. 2011. Calcium insufficiency accelerates type 1 diabetes in Vitamin D receptor-Deficient nonobese diabetic (NOD) mice. Endocrinology 152:4620-4629. PMCID: PMC3230053
Driver JP, Serreze DV, Chen YG. 2011. Mouse models for the study of autoimmune type 1 diabetes: a NOD to similarities and differences to human disease. Semin Immunopathol 33:67-87. Review
Niens M, Grier AE, Marron M, Kay TW, Greiner DL, Serreze DV. 2011. Prevention of "Humanized" diabetogenic CD8 T-cell responses in HLA-transgenic NOD mice by a multipeptide coupled-cell approach. Diabetes 60:1229-1236. PMCID: PMC3064096
Rivas EI, Driver JP, Garabatos N, Presa M, Mora C, Rodriguez F, Serreze DV, Stratmann T. 2011. Targeting of a T cell agonist peptide to lysosomes by DNA vaccination induces tolerance in the nonobese diabetic mouse. J Immunol 186:4078-4087
Serreze DV, Chapman HD, Niens M, Dunn R, Kehry MR, Driver JP, Haller M, Wasserfall C, Atkinson MA. 2011. Loss of intra-islet CD20 expression may complicate efficacy of B-cell-directed Type 1 diabetes therapies. Diabetes 60(11): 2914-2921. PMCID: PMC3198088
Cox SL, Stolp J, Hallahan NL, Counotte J, Zhang W, Serreze DV, Basten A, Silveira PA. 2010. Enhanced responsiveness to T-cell help causes loss of B-lymphocyte tolerance to a beta-cell neo-self antigen in type 1 diabetes prone NOD mice. Eur J Immunol 40:3413-3425
Driver JP, Scheuplein F, Chen YG, Grier AE, Wilson SB, Serreze DV. 2010. Invariant natural killer T-cell control of type 1 diabetes: a dendritic cell genetic decision of a silver bullet or Russian roulette. Diabetes 59:423-432. PMCID: PMC2809954
Scheuplein F, Rissiek B, Driver JP, Chen YG, Koch-Nolte F, Serreze DV. 2010. A recombinant heavy chain antibody approach blocks ART2 mediated deletion of an iNKT cell population that upon activation inhibits autoimmune diabetes. J Autoimmun 34:145-154. PMCID: PMC2822066
Serreze DV, Niens M, Kulik J, Dilorenzo TP. 2010. Bridging mice to men: using HLA transgenic mice to enhance the future prediction and prevention of autoimmune type 1 diabetes in humans. Methods Mol Biol 602: 119-134 Book chapter
Strom A, Sonier B, Chapman HD, Mojibian M, Wang GS, Slatculescu CR, Serreze DV, Scott FW. 2010. Peripherin-reactive antibodies in mouse, rabbit, and human blood. J Proteome Res 9:1203-1208. PMCID: PMC3023150