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Mitchison NA. J. B. S. Haldane, as I knew him. J Genet 2017; 96:729. [PMID: 29237877 DOI: 10.1007/s12041-017-0828-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Boak JL, Kölsch E, Mitchison NA. Immunological tolerance and inhibition by hapten. ANTIBIOTICA ET CHEMOTHERAPIA. FORTSCHRITTE. ADVANCES. PROGRES 2015; 15:98-109. [PMID: 5813678 DOI: 10.1159/000386774] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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Lukic ML, Arsenijevic N, Mitchison NA. Inflammation at the interface of innate and acquired immunity. Mol Immunol 2009; 47:1-2. [PMID: 19632723 DOI: 10.1016/j.molimm.2009.02.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2009] [Accepted: 02/11/2009] [Indexed: 11/19/2022]
Abstract
This is the short summary of the presentation at the 2nd Belgrade Meeting on Immunoregulation entitled "Inflammation at the interface of Innate and Acquired Immunity" held recently under the auspice of European Federation of Immunological Societies and organized by Medical School, University of Kragujevac.
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Flynn TH, Mitchison NA, Ono SJ, Larkin DFP. Aqueous humor alloreactive cell phenotypes, cytokines and chemokines in corneal allograft rejection. Am J Transplant 2008; 8:1537-43. [PMID: 18557741 DOI: 10.1111/j.1600-6143.2008.02285.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
As biopsies are not taken at the time of human corneal allograft rejection, most information on the early cellular changes in rejection is from animal models. We examined the phenotype of alloreactive cells present in the human anterior chamber during corneal graft rejection by flow cytometry and quantified aqueous humor levels of cytokines and chemokines using cytometric bead array. Aqueous and peripheral blood samples were taken from patients with graft endothelial rejection (n = 11) and from control patients undergoing cataract surgery (n = 8). CD45(+)CD4(+), CD45(+)CD8(+) and CD45(+)CD14(+) cells were found in aqueous during rejection; no CD45(+) cells were seen in control samples. Higher proportions of CD45(+) cells found in aqueous during rejection were CD14(+), denoting monocyte/macrophage lineage, than were CD4(+) or CD8(+). Large elevations were seen in aqueous levels of IL-6, MCP-1 and IP-10 during rejection compared with controls; smaller but still statistically significant increases were seen in MIP-1alpha and eotaxin. The role of CD14(+) cells in allorejection is unclear as is the potential of these chemokines and their receptors as therapeutic targets. Aqueous humor samples offer a unique opportunity to analyze components of the allogeneic response in direct contact with donor tissue but without artifacts inherent in examination of tissue.
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Mitchison NA. T cell recognition and interaction in the immune system. CIBA FOUNDATION SYMPOSIUM 2008:57-81. [PMID: 6216081 DOI: 10.1002/9780470720721.ch5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
This paper discusses mechanisms of regulation within the immune system. The only cells known to be specialized for regulatory activity within this system are helper and suppressor T cells. Like other T cells, most of these cells recognize antigen only in association with products of the major histocompatibility complex. This is a mechanism which ensures that these cells function appropriately, by being activated by and exerting their effects upon their proper cellular targets. It is likely but not certain that this mechanism of dual recognition is involved in the acquisition of self tolerance, and that inappropriate associations may be a factor in the induction of autoimmunity. There is extensive but circumstantial evidence that regulatory T cells govern to a large extent not only the induction but also the course (relapse and remission) of autoimmunity. An understanding of the mechanisms involved in activating suppressor T cells is of special importance for the treatment and prevention of autoimmune disease. A variety of factors which favour activation of suppression have been identified in experimental studies. These include the nature of the antigen, the way in which it reaches the immune system, antigenic dosage, and the involvement of antigen-presenting cells. It is proposed that certain cells within the suppressor cell circuit (suppressor-effector cells) do not operate dual recognition, and that this may explain the factors which favour suppression. The high incidence of sex-linked immunodeficiency diseases is discussed. It is proposed that this can be accounted for, at least in part, by the preferential elimination of autosomal deleterious genes in the heterozygotes. This emphasizes the importance of measuring the fitness of carriers of these diseases.
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Abstract
A comprehensive collection of mouse major histocompatibility complex (MHC) promoter and exon 2 sequences is here presented and analysed. It covers the three best known class II genes and one class I gene, and includes new wild mouse sequences from the 'w' back-cross strains and from the Jackson collection. All sequences are in GenBank, and the new exon sequences largely confirm previous typing by serology and immune function. As in human leucocyte antigen (HLA), the overall nucleotide diversity is higher in the class II genes, in keeping with their more diverse function. Diversity along the promoters is highest in the region of known transcription factor binding, most notably in and around the CRE and rCAAT sequences. This distribution parallels that of maximum single nucleotide polymorphism impact previously obtained with reporter constructs. Taking into account the low nucleotide diversity of the CIITA promoter, we conclude that MHC promoters are likely to have diversified through co-evolution with their exons, while themselves also directly subject to natural selection. The H2Eb(p) alleles form a distinct group, associated with their lack of the recombination hot spot located between exon 2 and exon 3. The collection is expected to prove useful in guiding functional and evolutionary studies.
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Brent L, Cohen IR, Doherty PC, Feldmann M, Matzinger P, Holgate ST, Lachmann P, Mitchison NA, Nossal G, Rose NR, Zinkernagel R. Crystal-ball gazing--the future of immunological research viewed from the cutting edge. Clin Exp Immunol 2007; 147:1-10. [PMID: 17177957 PMCID: PMC1810455 DOI: 10.1111/j.1365-2249.2006.03234.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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Marks DJB, Mitchison NA, Segal AW, Sieper J. Can unresolved infection precipitate autoimmune disease? Curr Top Microbiol Immunol 2006; 305:105-25. [PMID: 16724803 DOI: 10.1007/3-540-29714-6_6] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Autoimmune diseases are frequently postulated to arise as post-infectious phenomena. Here we survey the evidence supporting these theories, with particular emphasis on Crohn's disease and ankylosing spondylitis. Direct proof that infection establishes persistent autoimmunity remains lacking, although it may provoke a prolonged inflammatory response when occurring on a susceptible immunological background. The argument of infective causality is by no means trivial, since it carries important consequences for the safety of vaccine development.
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Mitchison NA, Harbord M, Hankin A, Roes J. Conditional haploinsufficiency of NCF1 (encoding p47(phox)), a signaling gene with a heterozygous phenotype potentially subject to natural selection. Immunol Lett 2005; 97:63-7. [PMID: 15626477 DOI: 10.1016/j.imlet.2004.09.015] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2004] [Revised: 09/06/2004] [Accepted: 09/23/2004] [Indexed: 11/16/2022]
Abstract
Even a minor degree of haploinsufficiency could eventually reduce the frequency of an autosomal immunodeficiency disease. Searching for such a condition, we have re-examined the phenotype of mice +/- for the NCF1 gene encoding p47(phox) and humans +/- for NCF1 and NCF2 using a procedure that allowed the respiratory burst of granulocytes and macrophages to be measured simultaneously. The mice showed significant haploinsufficiency in granulocytes but not in macrophages (i.e. conditional haploinsufficiency). Our human data were obtained from blister cells, and were too scattered to allow a firm conclusion. In view of recent re-evaluation of the role of the respiratory burst these findings are compatible with the view that haploinsufficiency occurs particularly among rate-limiting genes that operate in regulatory/signaling pathways.
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Mitchison NA, Ono SJ, Stephens HA. Does the polymorphism of MHC class II promoters matter? Cell Immunol 2005; 233:162-5. [PMID: 15953596 DOI: 10.1016/j.cellimm.2005.04.014] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2005] [Accepted: 04/21/2005] [Indexed: 11/18/2022]
Abstract
The promoters of genes of the major histocompatibility complex vary not only because of linkage disequilibrium with their coding sequences but also, we argue, because of natural selection that acts particularly strongly on MHC II gene promoters. Thus, the promoter of H2Eb varies more than that of H2K, to an extent that cannot be accounted for by coding variation, and the same applies to HLA.DRB1 in comparison with H2D. We discuss how transduction by lentivirus vectors followed by adoptive transfer of monoclonal T cells could be used to test the functional activity of variant mouse promoters in vivo, and how homologous recombination in suitable cell lines might provide a short cut to obtaining promoter knock-ins.
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Mitchison NA. The carrier effect in the secondary response to hapten-protein conjugates. II. Cellular cooperation. Eur J Immunol 2004; 1:18-27. [PMID: 14978857 DOI: 10.1002/eji.1830010104] [Citation(s) in RCA: 473] [Impact Index Per Article: 23.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Mitchison NA. Genetic variation in the MHC II promoter: lessons for regulation and for comparative genomics. Folia Biol (Praha) 2002; 47:183-6. [PMID: 11768774] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
Sequence data have been accumulating that reveal variation in gene promoters of the immune system, notably in MHC class II, cytokines and chemokines. The variation is non-random: it occurs most often in proximity to and within certain regulatory elements such as CRE and NFY (in MHC class II these are respectively the X2 and Y boxes). These are elements that are widely used elsewhere in the genome, and appear to act as rheostats (modulators of expression) in contrast to the type of on-off switch operated by the RFX element that is unique to a single family of promoters such as MHC class II. It is proposed that a complex mouse phenotype described in Prague and elsewhere may reflect this pattern of variation in/around CRE. Such rheostats are expected to operate in other promoters. Their identification will be facilitated by short-range comparisons (e.g. human-chimp), and indeed this is a motive for extending comparative genomics.
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Abstract
The immunological synapse plays a central role in organising the immune system. Through their synaptic activity both T and B cells usually, but not always, acquire the information that critically determines the level and nature of the responses that they make. For T cells much of that information comes from epicrine and paracrine cell-cell interactions in the cluster that forms around a dendritic cell. These interactions are being dissected by experiments in which two populations of TCR-transgenic T cells are combined in vivo. Another important aspect of synaptic activity is the way in which different levels of expression of MHC class II molecules influence Th1/Th2 balance. In exploring this form of control we are learning something of general importance about cis-regulation.
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Jeffery R, Mitchison NA. IL-6 polymorphism, anti-IL-6 therapy and animal models of multiple myeloma. Cytokine 2001; 16:87. [PMID: 11741346 DOI: 10.1006/cyto.2001.0983] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Mitchison NA. Peter Brian Medawar: 28 February 1915-2 October 1987. BIOGRAPHICAL MEMOIRS OF FELLOWS OF THE ROYAL SOCIETY. ROYAL SOCIETY (GREAT BRITAIN) 2001; 35:283-301. [PMID: 11622280] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
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Abstract
Collagen-induced arthritis is a well-established model of chronic inflammatory arthritis. We here introduce a development of this model which combines the benefits of adoptive transfer and sequential relapse. DBA/1 x B10.Q F1 hybrid mice were immunised with bovine type II collagen, and those which developed a sufficiently high level of arthritis served as donors of spleen cells transferred into BALB/c SCID hosts. After boosting with 500 microg collagen, the development of host arthritis was monitored over a period of up to 256 days, during which up to three successive peaks were detected. In comparison with bovine collagen, mouse collagen used for boosting induced a lower initial peak but higher relapses. As expected, the transferred disease was more uniform than the freshly induced one. Previous information suggests that a shifting cytokine balance between protective and aggressive T cells may account for the relapse and remission. This study provides a model of relapsing polyarthritis, obtained with normal immunocytes boosted with a well-defined protein antigen in animals not themselves treated with adjuvant. As such it is relevant to the etiology of inflammatory arthritis in man, and, if further developed, could be of value for testing new therapeutic strategies.
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Abstract
The extensive polymorphism revealed in non-coding gene-regulatory sequences, particularly in the immune system, suggests that this type of genetic variation is functionally and evolutionarily far more important than has been suspected, and provides a lead to new therapeutic strategies.
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Mitchison NA, Katz DR, Chain B. Self/nonself discrimination among immunoregulatory (CD4) T cells. Semin Immunol 2000; 12:179-83; discussion 257-344. [PMID: 10910737 DOI: 10.1006/smim.2000.0229] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
This review covers work on immunological tolerance from 1962 up to the present, focusing on the Th, CD4+ compartment of the immune system. The principle mechanism of tolerance is identified as deletion, occurring centrally and in the periphery. In the periphery, deletion is the normal response of CD4 T cells to soluble monomeric proteins that occurs when activation (mainly of dendritic cells) is avoided. Thus activation and the signals which induce it are crucial to understanding S/NS discrimination, as has long been known. The thymus is important as the site where new T cells first see self-antigens, and as one largely shielded from activation, although deletion in the thymus and the periphery has the same threshold. The relative contribution of dendritic cells and developing T cells to deletion in the thymus remains unclear. Activation induced cell death, containment, anergy and deviation constitute subsidiary mechanisms, and sequestration/neglect is important in limiting the scope of deletion.
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Schuhbauer DM, Mitchison NA, Mueller B. Interaction within clusters of dendritic cells and helper T cells during initial Th1/Th2 commitment. Eur J Immunol 2000; 30:1255-62. [PMID: 10820370 DOI: 10.1002/(sici)1521-4141(200005)30:5<1255::aid-immu1255>3.0.co;2-w] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Cytokines are the main agents known to regulate Th1 / Th2 commitment, where they may operate through paracrine activity within clusters of T cells gathered around dendritic cells (DC). An in vitro system is used here to test this possibility, using clusters around DC composed of naive TCR-transgenic ovalbumin peptide 323 - 339-specific CD4(+) T cells as targets plus TCR-transgenic pigeon cytochrome C peptide 88 - 104-specific CD4(+) polarized Th1 or Th2 cells as inducers. The polarized inducer cells exerted their maximum effect when the two T cell populations were activated within the same cluster, implemented by allowing a single DC to present both their epitopes. This finding thus supports the paracrine hypothesis. The system was then employed to explore the role of individual cytokines by means of inhibition by monoclonal antibodies. Development of Th2 commitment proved strictly dependent on the IL-4 produced by the Th2 inducers. For Th1 commitment, IFN-gamma and IL-12 were both needed, but with IFN-gamma required only during the initial period of culture. The rapid timing observed under these conditions places constraints on the molecular basis of commitment, and appears accurately to reflect the physiological response in vivo.
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Mitchison NA, Schuhbauer D, Müller B. Natural and induced regulation of Th1/Th2 balance. SPRINGER SEMINARS IN IMMUNOPATHOLOGY 2000; 21:199-210. [PMID: 10666769 DOI: 10.1007/bf00812253] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Because Th1/Th2 balance is perturbed during immunological disease, the design of strategies aiming at its rectification has become a priority. The alteration of the balance in pregnancy so as to promote survival of the fetal allograft lends credibility to this aim. Attenuation of the activation signal delivered through the T cell receptor (TCR) represents a promising approach. It is supported by the high level of polymorphism in the MHC class II promoter, which regulates the natural TCR signal and thus modulates Th1/Th2 differentiation. Further support comes from the Th2 shift that occurs in JNK knockout mice, and with kinase inhibitors and anti-CD4 monoclonal antibodies applied in vitro. The approach has implications for nasal tolerance and inhibition of IL-12 production. The further range of options for Th1/Th2 modulation, which are presented throughout this issue of the journal, are here summarised and evaluated.
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