Immune System Diseases; Multiple Sclerosis; Musculoskeletal Diseases; Myasthenia Gravis; Nervous System Diseases; Neurology
The O’Connor laboratory, is part of the Department of Neurology and program in Human Translational Immunology (HTI) at Yale University School of Medicine. The aim of our research is to further elucidate the role that B cells play in disease. We are specifically interested in defining the mechanisms by which B cells, and the antibodies they produce, affect tissue damage in autoimmunity and participate in tumor biology. To this end we are engaged in determining the specificity of autoantibodies and understanding the mechanisms by which B cells organize in autoimmune tissue. Areas of special interest in our autoimmunity program include multiple sclerosis, inflammatory myopathy and myasthenia gravis. Our cancer program is currently focused on meningiomas and germ cell tumors.
Extensive Research Description
Multiple sclerosis. B-cell depletion therapy in MS results in a remarkable reduction in new inflammatory brain lesions and clinical relapses, indicating that B cells contribute to MS pathology. How they do so is not well understood. We have built a program that is focused on furthering the understanding of the role that B cells and antibodies play in the pathology of MS. To this end, my group is investigating the following fundamental questions in MS: What are the antigen targets of MS B cells? Through the application of novel technologies, we demonstrated that autoantibodies to the encephalogenic myelin antigens, MBP and MOG are uncommon in the serum and CSF of adult patients with MS [1-4]. This turned our interest toward the B cells that accumulate at the site of tissue injury, the MS CNS. Here, we are elucidating the antigen specificity of B cells that reside within MS lesions. Our strategy harnesses the adaptive response of the humoral immune system by using the machinery of the B cells present in these tissues to isolate autoantigens . Laser capture micro-dissection is used to isolate single B cells directly from CNS tissue. Single-cell PCR then amplifies the antibody variable regions, sequencing of which provides information concerning expanded clones and evidence of those that have experienced antigen-driven stimulation. Then, large amounts of recombinant, whole IgG from selected clones are produced. The IgG is then used to capture antigens from candidate sources. The precise molecular definition of isolated antigen(s) is then determined through sophisticated mass spectrometric methodologies. To date, we have isolated and identified a number of candidate autoantigens, validation of which is under way. What is the relationship between the antibodies and the B cells present in the CSF and CNS tissue and to those in the periphery? While B cells and antibodies are present in the CSF and CNS tissue of patients with MS, the relationship among them is not understood. We have constructed immunoglobulin transcriptomes and proteomes from CNS tissue and CSF that allowed us to determine that these compartmentalized B cells and antibodies are clonally related [6, 7]. We have now turned our attention toward determining how these cells are related to the peripheral B cell repertoire. We are currently using high-throughput sequencing to build immunoglobulin transcriptomes from the cervical lymph nodes, which will be compared to those derived from CNS lesions and the CSF. How do MS CNS B cells function as antigen-presenting cells? We are developing a model system engineered to examine the role of human MS CNS-derived immunoglobulin in the pathogenic progression of CNS demyelination. Specifically, we will build a mouse model genetically engineered to develop B cells expressing immunoglobulin derived from pervasive human MS CNS clones. This model will allow the study of the contribution that MS CNS-derived immunoglobulin and B cells make to CNS demyelination and tissue injury
Myasthenia gravis. Autoreactive B-cells are thought to play an important role in the immunopathogenesis of MG. Early studies, including one at Yale, indicate that B cell depletion therapy is beneficial to MG patients . It is unclear what specific changes in the immune system are associated with the observed clinical improvement. Accordingly, the rationale for this work is to further understand rituximab’s mechanism of action by measuring its effects on immunity in MG. Molecular and cellular immune system components, which putatively participate in the pathology of MG, will be measured at points prior to, during and after rituximab-mediated B cell depletion. We are developing/adapting immunoassays so that we can measure: Autoantibody titer of MuSK and AChR; Antigen specific B cells and plasma cells; Repertoire and characteristics of antigen specific B cells; Antigen specific T-helper cells; Cytokine profiles of antigen specific T cells. We expect to identify changes in the immune system of MG patients undergoing treatment and these data will be related to measurements of clinical outcome. This work represents a first step toward gaining a more complete understanding of the immune mechanisms underlying treatment of MG with rituximab and will lead to new ways to prevent or treat the disease.
The inflammatory myopathies are a group of autoimmune diseases characterized by progressive skeletal muscle weakness associated with inflammatory cell infiltration within the muscle. The muscle mRNA from a subset of IM patients harbors an abundance of Ig transcripts. Although sparse numbers of CD19 or CD20 B cells are present in IM muscle tissue, we reported that large numbers of CD138 plasma cells are present and that these cells are the source of the Ig transcripts. These findings led us to hypothesize that we would find evidence of an Ag-driven immune response in the tissue of patients with particular IMs. Through investigating the B cell and plasma cell Ig repertoire in muscle biopsies we confirmed that such an antigen-driven response was occurring in this autoimmune tissue . We then set out to identify the antigen driving this response using recombinant IgG derived from plasma cells harbored in the muscle tissue. We are currently evaluating the validity of a novel muscle-associated autoantigen isolated using this strategy.
Our cancer program is currently focused on meningiomas and germ cell tumors. These tumors invariably harbor an immune cell infiltrate comprised, in part, of B cells, yet little is known of their role. We are using novel strategies to understand further the characteristics of the B cells commonly found within these tumors. A variety of procedures for the isolation of tumor antigens exist, yet the identification of real and reliable tumor-specific structures is difficult. Thus, our goal is to identify tumor-specific antigen(s) by harnessing the adaptive response of the humoral immune system present in the tumor microenvironment. Such molecular tools represent a sophisticated and reliable strategy both to investigate tumor-associated antibody specificity and to discover novel, tumor-associated antigens that can be used as potential targets in tumor diagnostics or therapeutics. Our work has focused on germ cell tumors, a principal feature of which is that they invariably harbor a prominent immune cell infiltrate. Data collected by our group indicate that germ cell tumors drive tumor-associated B cells toward antibody production that targets specific tumor antigens . To isolate these antigens we have adapted the strategy used in our MS antigen discovery program (described above). The identification of tumor-specific antigens represents a fundamental step toward understanding the biology and the role of the immune system in this tumor family. Moreover, novel tumor antigens may lead to the development of targeted immunotherapy that may be highly efficacious and better tolerated than current treatment strategies.
Related B cell clones populate the meninges and parenchyma of patients with multiple sclerosis (*co-senior authors).
Lovato, L., S. N. Willis, S. J. Rodig, T. Caron, S. E. Almendinger, O. W. Howell, R. Reynolds, K. C. O'Connor* and D. A. Hafler* (2011). Related B cell clones populate the meninges and parenchyma of patients with multiple sclerosis (*co-senior authors). Brain 134(Pt 2): p534 PMC3030766
The microenvironment of germ cell tumors harbors a prominent antigen-driven humoral response.
Willis, S. N., S. S. Mallozzi, S. Rodig, K. Cronk, S. L. McArdel, T. Caron, G. Pinkus, L. Lovato, K. L. Shampain, D. E. Anderson, R. C. E. Anderson, J. Bruce and K. C. O’Connor (2009). The microenvironment of germ cell tumors harbors a prominent antigen-driven humoral response. J. Immunol. 182: p3310
O'Connor (2009). Epstein-Barr virus infection is not a characteristic feature of multiple sclerosis brain.
Willis, S. N., C. Stadelmann, S. J. Rodig, T. Caron, S. Gattenloehner, S. S. Mallozzi, J. E. Roughan, S. E. Almendinger, M. M. Blewett, W. Bruck, D. A. Hafler and K. C. O'Connor (2009). Epstein-Barr virus infection is not a characteristic feature of multiple sclerosis brain. Brain 132(Pt 12): p3318 PMC2792367
Full List of PubMed Publications
- Yi JS, Guptill JT, Stathopoulos P, Nowak RJ, O'Connor KC: B cells in the pathophysiology of myasthenia gravis. Muscle Nerve. 2017 Sep 20; 2017 Sep 20. PMID: 28940642
- Vander Heiden JA, Stathopoulos P, Zhou JQ, Chen L, Gilbert TJ, Bolen CR, Barohn RJ, Dimachkie MM, Ciafaloni E, Broering TJ, Vigneault F, Nowak RJ, Kleinstein SH, O'Connor KC: Dysregulation of B Cell Repertoire Formation in Myasthenia Gravis Patients Revealed through Deep Sequencing. J Immunol. 2017 Feb 15; 2017 Jan 13. PMID: 28087666
- Robeson KR, Kumar A, Keung B, DiCapua DB, Grodinsky E, Patwa HS, Stathopoulos PA, Goldstein JM, O'Connor KC, Nowak RJ: Durability of the Rituximab Response in Acetylcholine Receptor Autoantibody-Positive Myasthenia Gravis. JAMA Neurol. 2017 Jan 1. PMID: 27893014
- Cui A, Di Niro R, Vander Heiden JA, Briggs AW, Adams K, Gilbert T, O'Connor KC, Vigneault F, Shlomchik MJ, Kleinstein SH: A Model of Somatic Hypermutation Targeting in Mice Based on High-Throughput Ig Sequencing Data. J Immunol. 2016 Nov 1; 2016 Oct 5. PMID: 27707999
- Lee JY, Stathopoulos P, Gupta S, Bannock JM, Barohn RJ, Cotzomi E, Dimachkie MM, Jacobson L, Lee CS, Morbach H, Querol L, Shan JL, Vander Heiden JA, Waters P, Vincent A, Nowak RJ, O'Connor KC: Compromised fidelity of B-cell tolerance checkpoints in AChR and MuSK myasthenia gravis. Ann Clin Transl Neurol. 2016 Jun; 2016 Apr 27. PMID: 27547772
- Chastre A, Hafler DA, O'Connor KC: Evaluation of KIR4.1 as an Immune Target in Multiple Sclerosis. N Engl J Med. 2016 Apr 14. PMID: 27074083
- Cao Y, Amezquita RA, Kleinstein SH, Stathopoulos P, Nowak RJ, O'Connor KC: Autoreactive T Cells from Patients with Myasthenia Gravis Are Characterized by Elevated IL-17, IFN-γ, and GM-CSF and Diminished IL-10 Production. J Immunol. 2016 Mar 1; 2016 Jan 29. PMID: 26826242
- Hu MY, Stathopoulos P, O'connor KC, Pittock SJ, Nowak RJ: Current and future immunotherapy targets in autoimmune neurology. Handb Clin Neurol. 2016. PMID: 27112694
- Willis SN, Stathopoulos P, Chastre A, Compton SD, Hafler DA, O'Connor KC: Investigating the Antigen Specificity of Multiple Sclerosis Central Nervous System-Derived Immunoglobulins. Front Immunol. 2015; 2015 Nov 25. PMID: 26648933
- Sandiego CM, Gallezot JD, Pittman B, Nabulsi N, Lim K, Lin SF, Matuskey D, Lee JY, O'Connor KC, Huang Y, Carson RE, Hannestad J, Cosgrove KP: Imaging robust microglial activation after lipopolysaccharide administration in humans with PET. Proc Natl Acad Sci U S A. 2015 Oct 6; 2015 Sep 18. PMID: 26385967
- Paltiel AD, Ingvarsson E, Lee DK, Leff RL, Nowak RJ, Petschke KD, Richards-Shubik S, Zhou A, Shubik M, O'Connor KC: Demographic and clinical features of inclusion body myositis in North America. Muscle Nerve. 2015 Oct; 2015 Feb 17. PMID: 25557419
- Xu GJ, Kula T, Xu Q, Li MZ, Vernon SD, Ndung'u T, Ruxrungtham K, Sanchez J, Brander C, Chung RT, O'Connor KC, Walker B, Larman HB, Elledge SJ: Viral immunology. Comprehensive serological profiling of human populations using a synthetic human virome. Science. 2015 Jun 5. PMID: 26045439
- Park E, Gallezot JD, Delgadillo A, Liu S, Planeta B, Lin SF, O'Connor KC, Lim K, Lee JY, Chastre A, Chen MK, Seneca N, Leppert D, Huang Y, Carson RE, Pelletier D: (11)C-PBR28 imaging in multiple sclerosis patients and healthy controls: test-retest reproducibility and focal visualization of active white matter areas. Eur J Nucl Med Mol Imaging. 2015 Jun; 2015 Apr 2. PMID: 25833352
- Bennett JL, O'Connor KC, Bar-Or A, Zamvil SS, Hemmer B, Tedder TF, von Büdingen HC, Stuve O, Yeaman MR, Smith TJ, Stadelmann C: B lymphocytes in neuromyelitis optica. Neurol Neuroimmunol Neuroinflamm. 2015 Jun; 2015 May 7. PMID: 25977932
- Waters P, Woodhall M, O'Connor KC, Reindl M, Lang B, Sato DK, Juryńczyk M, Tackley G, Rocha J, Takahashi T, Misu T, Nakashima I, Palace J, Fujihara K, Leite MI, Vincent A: MOG cell-based assay detects non-MS patients with inflammatory neurologic disease. Neurol Neuroimmunol Neuroinflamm. 2015 Jun; 2015 Mar 19. PMID: 25821844
- Kleffel S, Vergani A, Tezza S, Ben Nasr M, Niewczas MA, Wong S, Bassi R, D'Addio F, Schatton T, Abdi R, Atkinson M, Sayegh MH, Wen L, Wasserfall CH, O'Connor KC, Fiorina P: Interleukin-10+ regulatory B cells arise within antigen-experienced CD40+ B cells to maintain tolerance to islet autoantigens. Diabetes. 2015 Jan; 2014 Sep 3. PMID: 25187361
- Stern JN, Yaari G, Vander Heiden JA, Church G, Donahue WF, Hintzen RQ, Huttner AJ, Laman JD, Nagra RM, Nylander A, Pitt D, Ramanan S, Siddiqui BA, Vigneault F, Kleinstein SH, Hafler DA, O'Connor KC: B cells populating the multiple sclerosis brain mature in the draining cervical lymph nodes. Sci Transl Med. 2014 Aug 6. PMID: 25100741
- Vander Heiden JA, Yaari G, Uduman M, Stern JN, O'Connor KC, Hafler DA, Vigneault F, Kleinstein SH: pRESTO: a toolkit for processing high-throughput sequencing raw reads of lymphocyte receptor repertoires. Bioinformatics. 2014 Jul 1; 2014 Mar 10. PMID: 24618469
- Vaughan K, Peters B, O'Connor KC, Martin R, Sette A: A molecular view of multiple sclerosis and experimental autoimmune encephalitis: what can we learn from the epitope data? J Neuroimmunol. 2014 Feb 15; 2013 Dec 12. PMID: 24365494
- Keung B, Robeson KR, DiCapua DB, Rosen JB, O'Connor KC, Goldstein JM, Nowak RJ: Long-term benefit of rituximab in MuSK autoantibody myasthenia gravis patients. J Neurol Neurosurg Psychiatry. 2013 Dec; 2013 Jun 12. PMID: 23761915
- Yaari G, Vander Heiden JA, Uduman M, Gadala-Maria D, Gupta N, Stern JN, O'Connor KC, Hafler DA, Laserson U, Vigneault F, Kleinstein SH: Models of somatic hypermutation targeting and substitution based on synonymous mutations from high-throughput immunoglobulin sequencing data. Front Immunol. 2013; 2013 Nov 15. PMID: 24298272
- Fang L, Lowther DE, Meizlish ML, Anderson RC, Bruce JN, Devine L, Huttner AJ, Kleinstein SH, Lee JY, Stern JN, Yaari G, Lovato L, Cronk KM, O'Connor KC: The immune cell infiltrate populating meningiomas is composed of mature, antigen-experienced T and B cells. Neuro Oncol. 2013 Nov; 2013 Aug 26. PMID: 23978377
- Hannestad J, DellaGioia N, Gallezot JD, Lim K, Nabulsi N, Esterlis I, Pittman B, Lee JY, O'Connor KC, Pelletier D, Carson RE: The neuroinflammation marker translocator protein is not elevated in individuals with mild-to-moderate depression: a [¹¹C]PBR28 PET study. Brain Behav Immun. 2013 Oct; 2013 Jul 9. PMID: 23850810
- Querol L, Clark PL, Bailey MA, Cotsapas C, Cross AH, Hafler DA, Kleinstein SH, Lee JY, Yaari G, Willis SN, O'Connor KC: Protein array-based profiling of CSF identifies RBPJ as an autoantigen in multiple sclerosis. Neurology. 2013 Sep 10; 2013 Aug 6. PMID: 23921886
- Kinnunen T, Chamberlain N, Morbach H, Cantaert T, Lynch M, Preston-Hurlburt P, Herold KC, Hafler DA, O'Connor KC, Meffre E: Specific peripheral B cell tolerance defects in patients with multiple sclerosis. J Clin Invest. 2013 Jun; 2013 May 15. PMID: 23676463
- Ray A, Amato AA, Bradshaw EM, Felice KJ, DiCapua DB, Goldstein JM, Lundberg IE, Nowak RJ, Ploegh HL, Spooner E, Wu Q, Willis SN, O'Connor KC: Autoantibodies produced at the site of tissue damage provide evidence of humoral autoimmunity in inclusion body myositis. PLoS One. 2012; 2012 Oct 5. PMID: 23071619
- Walker CA, Huttner AJ, O'Connor KC: Cortical injury in multiple sclerosis; the role of the immune system. BMC Neurol. 2011 Dec 6; 2011 Dec 6. PMID: 22145746
- Lovato L, Willis SN, Rodig SJ, Caron T, Almendinger SE, Howell OW, Reynolds R, O'Connor KC, Hafler DA: Related B cell clones populate the meninges and parenchyma of patients with multiple sclerosis. Brain. 2011 Feb; 2011 Jan 7. PMID: 21216828