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Petrie HT, Zúñiga-Pflücker JC. Zoned out: functional mapping of stromal signaling microenvironments in the thymus. Annu Rev Immunol 2007; 25:649-79. [PMID: 17291187 DOI: 10.1146/annurev.immunol.23.021704.115715] [Citation(s) in RCA: 343] [Impact Index Per Article: 20.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
All hematopoietic cells, including T lymphocytes, originate from stem cells that reside in the bone marrow. Most hematopoietic lineages also mature in the bone marrow, but in this respect, T lymphocytes differ. Under normal circumstances, most T lymphocytes are produced in the thymus from marrow-derived progenitors that circulate in the blood. Cells that home to the thymus from the marrow possess the potential to generate multiple T and non-T lineages. However, there is little evidence to suggest that, once inside the thymus, they give rise to anything other than T cells. Thus, signals unique to the thymic microenvironment compel multipotent progenitors to commit to the T lineage, at the expense of other potential lineages. Summarizing what is known about the signals the thymus delivers to uncommitted progenitors, or to immature T-committed progenitors, to produce functional T cells is the focus of this review.
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Affiliation(s)
- Howard T Petrie
- Scripps Florida Research Institute, Jupiter, Florida 33458, USA.
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2
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Paessens LC, Fluitsma DM, van Kooyk Y. Haematopoietic antigen-presenting cells in the human thymic cortex: evidence for a role in selection and removal of apoptotic thymocytes. J Pathol 2007; 214:96-103. [DOI: 10.1002/path.2260] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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3
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Choi EY, Jung KC, Park HJ, Chung DH, Song JS, Yang SD, Simpson E, Park SH. Thymocyte-Thymocyte Interaction for Efficient Positive Selection and Maturation of CD4 T Cells. Immunity 2005; 23:387-96. [PMID: 16226504 DOI: 10.1016/j.immuni.2005.09.005] [Citation(s) in RCA: 92] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2005] [Revised: 08/25/2005] [Accepted: 09/02/2005] [Indexed: 01/20/2023]
Abstract
Despite numerous reports on MHC class II expression by T cells from a wide spectrum of mammalian species including humans, the biological relevance of this phenomenon has never been tested with appropriately designed animal models. To address this issue, we developed mouse models in which immature thymocytes are the only positively selecting antigen-presenting cells in the thymus. In these mice, CD4+ T cells were generated with the appropriate maturation phenotype and showed a diverse repertoire of TCR Vbetas. The CD4+ T cells were functionally competent, mediating effective allogeneic responses that involved polyclonal TCR Vbetas. These results suggest that the thymocyte-thymocyte (T-T) interaction operates as an independent pathway for CD4+ T cell selection in the thymi of species with MHC II-positive thymocytes. This T-T interaction appears to be the basis for the generation of donor MHC-restricted CD4+ T cells in xenogeneic hosts.
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Affiliation(s)
- Eun Young Choi
- Graduate Program of Immunology, Seoul National University College of Medicine, Seoul 110-799, Korea
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4
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Onoé K, Gotohda T, Nishihori H, Aranami T, Iwabuchi C, Iclozan C, Morohashi T, Ogasawara K, Good RA, Iwabuchi K. Positive and negative selection of T cell repertoires during differentiation in allogeneic bone marrow chimeras. Transpl Immunol 2004; 12:79-88. [PMID: 14551035 DOI: 10.1016/s0966-3274(03)00012-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
T cells acquire immune functions during expansion and differentiation in the thymus. Mature T cells respond to peptide antigens (Ag) derived from foreign proteins when these peptide Ag are presented on the self major histocompatibility complex (MHC) molecules but not on allo-MHC. This is termed self-MHC restriction. On the other hand, T cells do not induce aggressive responses to self Ag (self-tolerance). Self-MHC restriction and self-tolerance are not genetically determined but acquired a posteriori by positive and negative selection in the thymus in harmony with the functional maturation. Allogeneic bone marrow (BM) chimera systems have been a useful strategy to elucidate mechanisms underlying positive and negative selection. In this communication, the contribution of BM chimera systems to the investigation of the world of T-ology is discussed.
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MESH Headings
- Amino Acid Sequence
- Animals
- Antigen-Presenting Cells/immunology
- Antigens, Differentiation, T-Lymphocyte/analysis
- Bone Marrow Transplantation/immunology
- Cell Differentiation/immunology
- Clonal Deletion/immunology
- Columbidae
- Cytochromes c/genetics
- Cytochromes c/immunology
- Flow Cytometry
- Graft vs Host Reaction/immunology
- Immune Tolerance/immunology
- Lymphocyte Activation/immunology
- Lymphocyte Culture Test, Mixed
- Lymphocyte Depletion
- Major Histocompatibility Complex/immunology
- Mice
- Mice, Inbred AKR
- Mice, Inbred C57BL
- Models, Immunological
- Peptides/genetics
- Peptides/immunology
- Receptors, Antigen, T-Cell/immunology
- T-Lymphocytes/chemistry
- T-Lymphocytes/immunology
- T-Lymphocytes, Cytotoxic/immunology
- Thymus Gland/cytology
- Transplantation Chimera/immunology
- Transplantation, Homologous
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Affiliation(s)
- Kazunori Onoé
- Institute for Genetic Medicine, Hokkaido University, Sapporo, Japan.
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5
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Yasutomo K, Lucas B, Germain RN. TCR signaling for initiation and completion of thymocyte positive selection has distinct requirements for ligand quality and presenting cell type. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2000; 165:3015-22. [PMID: 10975810 DOI: 10.4049/jimmunol.165.6.3015] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Thymocyte selection involves signaling by TCR engaging diverse self-peptide:MHC molecule ligands on various cell types in the cortex and medulla. Here we separately analyze early and late stages of selection to better understand how presenting cell type, ligand quality, and the timing of TCR signaling contribute to intrathymic differentiation. TCR transgenic CD4+CD8+ thymocytes (double positive (DP)) from MHC-deficient mice were stimulated using various presenting cells and ligands. The resulting CD69high cells were isolated and evaluated for maturation in reaggregate cultures with wild-type or MHC molecule-deficient thymic stroma with or without added hemopoietic dendritic cells (DC). Production of CD4+ T cells required TCR signaling in the reaggregates, indicating that transient recognition of self-ligands by DP is inadequate for full differentiation. DC bearing a potent agonist ligand could initiate positive selection, producing activated thymocytes that matured into agonist-responsive T cells in reaggregates lacking the same ligand. DC could also support the TCR signaling necessary for late maturation. These results argue that despite the negative role assigned to DC in past studies, neither the peptide:MHC molecule complexes present on DC nor any other signals provided by these cells stimulate only thymocyte death. These findings also indicate that unique epithelial ligands are not necessary for positive selection. They provide additional insight into the role of ligand quality in selection events and support the concept that following initiation of maturation from the DP state, persistent TCR signaling is characteristic of and perhaps required by T cells.
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MESH Headings
- Animals
- Antigen-Presenting Cells/classification
- Antigen-Presenting Cells/enzymology
- Antigen-Presenting Cells/immunology
- Antigen-Presenting Cells/metabolism
- Antigens, CD/biosynthesis
- Antigens, Differentiation, T-Lymphocyte/biosynthesis
- CD4 Antigens/biosynthesis
- CD4-Positive T-Lymphocytes/cytology
- CD4-Positive T-Lymphocytes/immunology
- CD4-Positive T-Lymphocytes/metabolism
- CD8 Antigens/biosynthesis
- Cell Aggregation/immunology
- Cell Differentiation/immunology
- Cell Survival/immunology
- Cells, Cultured
- Cytochrome c Group/immunology
- Cytochrome c Group/metabolism
- Dendritic Cells/enzymology
- Dendritic Cells/immunology
- Dendritic Cells/metabolism
- Histocompatibility Antigens Class II/metabolism
- Immunophenotyping
- Lectins, C-Type
- Ligands
- Lymphocyte Activation
- Major Histocompatibility Complex/immunology
- Mice
- Mice, Inbred C57BL
- Mice, Knockout
- Mice, Transgenic
- Peptides/agonists
- Peptides/immunology
- Peptides/metabolism
- Proto-Oncogene Proteins c-bcl-2/agonists
- Proto-Oncogene Proteins c-bcl-2/biosynthesis
- Receptors, Antigen, T-Cell/physiology
- Signal Transduction/immunology
- Stromal Cells/immunology
- Stromal Cells/metabolism
- T-Lymphocyte Subsets/cytology
- T-Lymphocyte Subsets/immunology
- T-Lymphocyte Subsets/metabolism
- Thymus Gland/cytology
- Thymus Gland/immunology
- Thymus Gland/metabolism
- Up-Regulation/immunology
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Affiliation(s)
- K Yasutomo
- Lymphocyte Biology Section, Laboratory of Immunology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA
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6
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Markert ML, Boeck A, Hale LP, Kloster AL, McLaughlin TM, Batchvarova MN, Douek DC, Koup RA, Kostyu DD, Ward FE, Rice HE, Mahaffey SM, Schiff SE, Buckley RH, Haynes BF. Transplantation of thymus tissue in complete DiGeorge syndrome. N Engl J Med 1999; 341:1180-9. [PMID: 10523153 DOI: 10.1056/nejm199910143411603] [Citation(s) in RCA: 209] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
BACKGROUND The DiGeorge syndrome is a congenital disorder that affects the heart, parathyroid glands, and thymus. In complete DiGeorge syndrome, patients have severely reduced T-cell function. METHODS We treated five infants (age, one to four months) with complete DiGeorge syndrome by transplantation of cultured postnatal thymus tissue. Follow-up evaluations included immune phenotyping and proliferative studies of peripheral-blood mononuclear cells plus biopsy of the thymus allograft. Thymic production of new T cells was assessed in peripheral blood by tests for T-cell-receptor recombination excision circles, which are formed from excised DNA during the rearrangement of T-cell-receptor genes. RESULTS After the transplantation of thymus tissue, T-cell proliferative responses to mitogens developed in four of the five patients. Two of the patients survived with restoration of immune function; three patients died from infection or abnormalities unrelated to transplantation. Biopsies of grafted thymus in the surviving patients showed normal morphologic features and active T-cell production. In three patients, donor T cells could be detected about four weeks after transplantation, although there was no evidence of graft-versus-host disease on biopsy or at autopsy. In one patient, the T-cell development within the graft was demonstrated to accompany the appearance of recently developed T cells in the periphery and coincided with the onset of normal T-cell function. In one patient, there was evidence of thymus function and CD45RA+CD62L+ T cells more than five years after transplantation. CONCLUSIONS In some infants with profound immunodeficiency and complete DiGeorge syndrome, the transplantation of thymus tissue can restore normal immune function. Early thymus transplantation - before the development of infectious complications - may promote successful immune reconstitution.
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Affiliation(s)
- M L Markert
- Department of Pediatrics, Duke Comprehensive Cancer Center, Duke University Medical Center, Durham, NC 27710, USA.
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7
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Zinkernagel RM, Althage A. On the role of thymic epithelium vs. bone marrow-derived cells in repertoire selection of T cells. Proc Natl Acad Sci U S A 1999; 96:8092-7. [PMID: 10393953 PMCID: PMC22193 DOI: 10.1073/pnas.96.14.8092] [Citation(s) in RCA: 72] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
T lymphocytes mature in the thymus to become functional T cells. Studies with chimeric mice and T cell receptor (TCR) transgenic (tg) mice have indicated that the major histocompatibility gene complex (MHC) of thymic radio-resistant (presumed to be epithelial) cells positively select the MHC-restricted T cell repertoire. Surprisingly, mice without a thymus reconstituted with an MHC-incompatible thymus generate effector T cells which are, in general, specific for the host and not for the thymic MHC. The present study reanalyzed this longstanding paradox in nude mice that were reconstituted with an MHC-incompatible thymus plus or minus immunologically defective bone marrow-derived cells or in nude mice expressing a transgenic T cell receptor. A pathway of thymus-dependent but thymic MHC-independent T cell maturation is revealed where expansion of the antiviral T cell repertoire depends on the MHC of bone marrow-derived cells. These results indicate an alternative, if not a general, pathway of T cell maturation and selection: the thymus may function essentially as an organ promoting T cell receptor expression; T cell specificity, however, reflects repertoire expansion plus cell survival and effector T cell induction driven by the MHC of bone marrow-derived cells. Therefore pure thymus defects can be efficiently reconstituted by allo- and xenogeneic thymic grafts.
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Affiliation(s)
- R M Zinkernagel
- Institute of Experimental Immunology, Department of Pathology, University of Zurich, Schmelzbergstrasse 12, CH 8091 Zürich, Switzerland.
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8
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Eibl MM, Wolf HM. Biologic consequences of defective major histocompatibility complex class II presentation. Curr Top Microbiol Immunol 1998; 232:217-40. [PMID: 9557400 DOI: 10.1007/978-3-642-72045-1_10] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- M M Eibl
- Institute of Immunology, University of Vienna, Austria
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9
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Abstract
ABSTRACT Human thymic dendritic cells (DC) represent a member of the bone marrow-derived dendritic cell family. They have a dendritic shape and are found in small numbers mainly at the corticomedullary border and in medullary regions of the thymus. Human thymic DC were isolated by density gradient separation, followed by treatment with CD2, CD7, CD1, and CD11b mAb and immunobeads magnetic separation. The resulting population contains 60-75% brightly HLA-DR+ cells which present the morphological characteristics of DC observed in situ. Extensive phenotypic analysis confirmed that they are of mesenchymal origin and that some express CD11a and CD54 molecules. Freshly isolated DC do not stain with a wide variety of anti-T-B and -monocyte or -macrophage mAb. However, they acquire the CD1 molecule after a few days in culture. By using a cell sorter we obtained 90-95% of purified human thymic DC. Functional studies have shown that human thymic DC are potent activators in mixed lymphocyte reactions, act as accessory cells in mitogenic thymocyte proliferation, increase the thymocyte proliferative response to a toxin signal, and produce IL-1. They also formed spontaneous physical associations with thymocytes, which raises questions about the implication of DC in differentiation and/or maturation processes of thymocytes.
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Affiliation(s)
- M Lafontaine
- Département de microbiologie et immunologie, Université de Montréal,Québec, Canada
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10
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Affiliation(s)
- J I Elliott
- Section of Transplantation Biology, Clinical Research Centre, Harrow, Middx., U.K
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11
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Hugo P, Kappler JW, Marrack PC. Positive selection of TcR alpha beta thymocytes: is cortical thymic epithelium an obligatory participant in the presentation of major histocompatibility complex protein? Immunol Rev 1993; 135:133-55. [PMID: 8282311 DOI: 10.1111/j.1600-065x.1993.tb00647.x] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- P Hugo
- Howard Hughes Medical Institute, National Jewish Center for Immunology and Respiratory Medicine, Denver, Colorado 80206
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12
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Pawlowski T, Elliott JD, Loh DY, Staerz UD. Positive selection of T lymphocytes on fibroblasts. Nature 1993; 364:642-5. [PMID: 8350923 DOI: 10.1038/364642a0] [Citation(s) in RCA: 80] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Thymocytes are selected for expression of alpha beta T-cell antigen receptors (TCR) which recognize antigen in conjunction with self-major histocompatibility complex (MHC) molecules. In the thymus the restriction element is imprinted on radioresistant stromal elements and on cells of haematopoietic origin. In mice negative for beta 2-microglobulin that are devoid of mature cytotoxic T lymphocytes, we find that intrathymic injection of different fibroblasts causes the maturation of CD4-CD8+TCRhigh thymocytes with distinct patterns of TCR V beta distribution. Here we show that in TCR-transgenic mice, intrathymic injection of L cells expressing the selecting H-2Kb molecule (L-Kb cells) reconstitutes the maturation of thymocytes bearing the transgenic TCR, and that in normal B10.BR (H-2k) mice, H-2Kb molecules expressed on L-Kb cells lead to the development of T lymphocytes with recognition restricted to H-2Kb. A class I MHC restriction element can thus be selected by interaction with fibroblasts, that is, cells of other than epithelial or haematopoietic origin.
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Affiliation(s)
- T Pawlowski
- Department of Medicine, National Jewish Center for Immunology and Respiratory Medicine, Denver, Colorado 80206
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13
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Markowitz JS, Auchincloss H, Grusby MJ, Glimcher LH. Class II-positive hematopoietic cells cannot mediate positive selection of CD4+ T lymphocytes in class II-deficient mice. Proc Natl Acad Sci U S A 1993; 90:2779-83. [PMID: 8464889 PMCID: PMC46179 DOI: 10.1073/pnas.90.7.2779] [Citation(s) in RCA: 75] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
Generation of immunocompetent alpha/beta T-cell receptor-positive T cells from CD4+CD8+ thymocytes depends upon their interaction with thymic major histocompatibility complex (MHC) molecules. This process of positive selection provides mature T cells that can recognize antigens in the context of self-MHC proteins. Previous studies investigating haplotype restriction in thymic and bone-marrow chimeras concluded that radioresistant thymic cortical epithelium directs the positive selection of thymocytes. There is controversy, however, as to whether intra- or extrathymic radiosensitive bone marrow-derived macrophage and dendritic cells also can mediate positive selection. To determine whether CD4+ T cells can be positively selected by hematopoietic cells, we generated chimeric animals expressing MHC class II molecules on either bone marrow-derived or thymic stromal cells by using a recently produced strain of MHC class II-deficient mice. CD4+ T cells developed only when class II MHC molecules were expressed on radioresistant thymic cells. In contrast to what recently has been observed for the selection of CD8+ T lymphocytes, MHC class II-positive bone marrow-derived cells were unable to mediate the selection of CD4+ T cells when the thymic epithelium lacked MHC class II expression. These data suggest that CD4+ and CD8+ T cells may be generated by overlapping, but not identical, mechanisms.
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Affiliation(s)
- J S Markowitz
- Department of Cancer Biology, Harvard School of Public Health, Boston, MA 02115
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14
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Abstract
Intrathymic differentiation of alpha beta TCR+ T cells depends on positive selection of CD4+CD8+ thymocytes by thymic major histocompatibility complex (MHC) molecules. Positive selection allows the maturation of only those T cells capable of restricted antigen recognition in the context of the hosts' MHC alleles. Studies of normal or T-cell receptor-transgenic mice engrafted with MHC-different bone marrow or thymuses support the conclusion that positive selection is directed by MHC molecules expressed on non-haematopoietic cells, presumably thymic epithelial cells. Here we, present contrary evidence that class I MHC molecules expressed by haematopoietic cell types direct positive selection of CD8+ T cells, though at a reduced rate compared with positive selection directed by thymic epithelial cells. The identity of cell types that direct positive selection bears directly on mechanistic models of the process, including the idea that thymic epithelial cell MHC molecules uniquely present specialized peptides that mediate positive selection, and the notion that thymic epithelial cells express unique differentiation-inducing cell surface molecules.
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Affiliation(s)
- M Bix
- Department of Molecular and Cell Biology, University of California, Berkeley 94720
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15
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Speiser DE, Stübi U, Zinkernagel RM. Extrathymic positive selection of αβ T-cell precursors in nude mice. Nature 1992; 355:170-2. [PMID: 1346064 DOI: 10.1038/355170a0] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
T lymphocytes expressing alpha beta T-cell receptors with sufficient affinity to major histocompatibility complex (MHC) molecules expressed on thymus epithelial cells are positively selected and mature to functional T cells. But several studies have demonstrated that athymic nude mice grafted with MHC-incompatible thymuses developed T cells specific for nude host rather than thymic MHC. We examined this paradox by analysing the specificity of T lymphocytes derived from nude mice. We report here that nude T lymphocyte precursors transferred to allogeneic SCID (severe combined immunodeficiency) mice with a functioning thymus (but lacking T or B cells) generated host MHC-restricted effector T cells but also contained T cells restricted to donor MHC. If nude T cells were depleted from nude lymphohaemopoietic donor cells before or after transfer, only host MHC-specific T cells matured. The results may explain the unusual MHC specificities of nude T lymphocytes described in earlier studies and demonstrate two separate differentiation steps: in nude mice, T cells may be positively selected for self-MHC restriction specificity extrathymically; then a functional thymus is required for efficient T cell maturation.
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Affiliation(s)
- D E Speiser
- Laboratory for Experimental Pathology, University Hospital, Zürich, Switzerland
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16
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Hugo P, Petrie HT. Multiple Routes for Late Intrathymic Precursors to Generate CD4+CD8+ Thymocytes. Mol Immunol 1992. [DOI: 10.1016/s1569-2558(08)60187-3] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
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17
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Murawska MB, Duijvestijn AM, Klatter FA, Ammerlaan W, Meedendorp B, Nieuwenhuis P. Differential kinetics of various subsets of thymic bone marrow-derived stromal cells in rat chimeras. Scand J Immunol 1991; 33:473-84. [PMID: 2017666 DOI: 10.1111/j.1365-3083.1991.tb01796.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Identification of those cells within the thymic stroma which are responsible for tolerance induction remains controversial. Evidence derived from studies of bone marrow chimeras or thymus transplants attributed this function to cells of haematopoietic origin, usually class II positive medullary dendritic cells (DC). Recent data suggest, however, that a stromal element located in the thymus cortex might be involved in negative selection. To further explore this issue we used immunohistology and immunocytology with a combination of allotype and cell type specific monoclonal antibodies (MoAb) to study the turnover of thymic stromal cells of haematopoietic origin in different rat models of allogeneic and congenic bone marrow (BM) radiation chimeras. Use of CFU-GM cultured BM inoculum for congenic recipients allowed us to distinguish between direct homing of donor myeloid cells and the delayed migration of the donor stem cell progeny after the post-irradiation recovery of the recipient. Our data indicate a heterogeneity in the turnover rate of thymic mobile stromal cells. While DC and a subset of macrophages located in the cortex as well as in the medulla (ED1+), within 4 weeks were virtually all of donor type, cortical macrophages detected by ED2 MoAbs were still incompletely replaced after a period as long as 20 weeks. Slow turnover, location and variable class II expression may imply a role for thymic cortical macrophages in (self-) tolerance induction.
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Affiliation(s)
- M B Murawska
- Department of Histology and Cell Biology, University of Groningen, The Netherlands
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18
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Ogasawara K, Fukushi N, Mishima M, Good RA, Onoé K. Ia restriction specificity of KLH-specific T cells from allogeneic bone marrow chimeras is influenced by histocompatibility at the H-2 and minor histocompatibility loci. Microbiol Immunol 1990; 34:1025-39. [PMID: 2098631 DOI: 10.1111/j.1348-0421.1990.tb01524.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Ia restriction specificity involved in T cell proliferative responses to keyhole limpet hemocyanin (KLH) has been analyzed using a variety of allogeneic bone marrow chimeras. The chimeric mice were prepared by reconstituting irradiated AKR, SJL, B10.BR and B10.A(4R) mice with bone marrow cells from B10 mice. When such chimeric mice had first been primed with KLH in complete Freund's adjuvant (CFA), T cells from H-2 incompatible fully allogeneic chimeras showed significantly higher responses to KLH in the presence of antigen-presenting cells (APC) of donor strain (B10) than APC of recipient strain. However, in H-2 subregion compatible chimeras, [B10----B10.A(4R)], which were matched at the H-2D locus and at minor histocompatible loci, the T cells could mount vigorous responses to KLH with antigen-presenting cells (APC) of either donor or recipient type. The same results were obtained as well with chimeras that had been thymectomized after full reconstitution of lymphoid tissues by donor-derived cells. A considerable proportion of KLH-specific T cell hybridomas established from [B10----B10.A(4R)] chimeras exhibited both I-Ab and I-Ak restriction specificities. The present findings indicate that the bias to donor Ia type of antigen specific T cells is determined by donor-derived APC present in the extrathymic environment but that cross-reactivity to the recipient Ia is influenced to some degree by histocompatibility between donor and recipient mice, even though the histocompatible H-2D locus and minor histocompatibility loci seem not to be directly involved in the I-A restricted responses studied herein.
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19
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Jordan RK, Chapman CJ, McLachlan SM, Milne D, Loveland BE, Robinson JH. IgG antibody and delayed-type hypersensitivity responses in nude mice grafted with thymic epithelium. Immunology 1990; 70:453-7. [PMID: 1975562 PMCID: PMC1384248] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
This study compared the ability of foetal thymic epithelium depleted of lymphocytes and dendritic cells, by low temperature or deoxyguanosine (dGuo) treatment in organ culture, to reconstitute T-cell function in nude mice. It is shown that renal capsule grafts of either type could promote the development of functional T lymphocytes in the periphery, as judged by in vivo assays. Both syngeneic and allogeneic thymic epithelium endowed nude mice with the capacity to mount IgG antibody and delayed-type hypersensitivity (DTH) responses to the T-dependent antigen ovalbumin (OVA). Functional reconstitution was accompanied by the appearance of Thy-1-bearing cells in the spleens of thymic grafted nude mice. The results from allogeneically grafted recipients show that a substantial population of peripheral T cells was present that collaborated with B cells and other antigen-presenting cells (APC) which do not express major histocompatibility complex (MHC) molecules of the thymus donor haplotype.
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20
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Kosaka H, Ogata M, Hikita I, Maruo S, Sugihara S, Matsubara H, Takai Y, Hamaoka T, Fujiwara H. Model for clonal elimination in the thymus. Proc Natl Acad Sci U S A 1989; 86:3773-7. [PMID: 2524833 PMCID: PMC287222 DOI: 10.1073/pnas.86.10.3773] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
A thymic stromal cell clone, MRL104.8a, expresses class I as well as class II H-2k antigens after exposure to gamma-interferon. This clone also produces thymic stroma-derived T-cell growth factor (TSTGF), which is distinct from other known interleukins and is capable of promoting the growth of various antigen-specific helper T cell (Th) clones without requiring a specific antigen or interleukin 2. When the keyhole limpet hemocyanin (KLH)-specific, I-Ek-restricted Th clone 9-16 was cultured on an Ia (I-Ak and I-Ek)-expressing MRL104.8a monolayer, potent proliferation of the 9-16 cells was induced by TSTGF produced by the monolayer. In contrast, the addition of KLH resulted in lethal growth inhibition of Th clone 9-16 cells. Another Th clone that is KLH-specific but I-Ab-restricted was capable of proliferating on the Iak-expressing MRL104.8a monolayer whether or not KLH was present. More importantly, death of Th clone 9-16 cells cultured on a MRL104.8a monolayer in the presence of KLH was almost completely prevented by the addition of anti-I-Ek or anti-CD3 monoclonal antibodies, which are capable of blocking antigen recognition by the T-cell receptor. However, when Th clone 9-16 cells were cultured in the presence of KLH but on a monolayer of MRL28.8a cells, another thymic stromal clone that expresses a comparable amount of I-Ek antigen but produces a marginal amount of TSTGF, cells did not die; a lethal effect was induced by adding TSTGF. These results indicate that the TSTGF-producing and Ia-expressing thymic stromal cells induce the continuous proliferation or selective elimination of each T-cell clone, depending on whether the T-cell receptor is stimulated by the relevant antigen associated with Ia molecules expressed on the stromal cell surface.
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Affiliation(s)
- H Kosaka
- Biomedical Research Center, Osaka University Medical School, Japan
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21
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LaRochelle GG, Jones KH. Kinetic analysis of thymocyte attachment to thymus stromal cells in culture by using phase-contrast and scanning electron microscopy. Anat Rec (Hoboken) 1989; 224:55-65. [PMID: 2658686 DOI: 10.1002/ar.1092240108] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Direct cellular contact between thymocytes and thymus stromal cells within the thymus appears to contribute to the maturation of thymocytes. Thymocyte-stromal cell complexes, formed in vivo, have been isolated by others and postulated to play a role in T-cell differentiation. These previous studies have been hampered, however, by a time-consuming isolation procedure from which only small numbers of these complexes are recovered. We have examined a model to study thymocyte-stromal cell complexes in vitro in which thymocytes are added to primary cultures of thymus stromal cells. In the present study, we found that thymocytes were histotypically selective in their attachment to thymus stromal cells. We also investigated the kinetics of thymocyte attachment to these thymus stromal cells. Cultures were examined at selected time intervals from 5 min through 3 days of incubation. Thymocyte attachment to stromal cells was a biphasic interaction, with maximum surface attachment at 15 min of cocultivation, followed by migration of thymocytes into the cultures. Morphological studies were confirmed by using 3H-leucine-labeled thymocytes and liquid scintigraphy. With increased time in culture, thymocytes became amoeboid and migrated between the layers of stromal cells where thymocyte mitotic figures were seen at 4 and 8 hr. In some cases it appeared that stromal cells, which often grew two to three cell layers deep, played an active role in enclosing thymocytes within the cultures. Large numbers of viable thymocytes were observed in the cultures at 24 hr. The number of thymocytes then decreased progressively on days 2 and 3, when relatively few were found within the layers of the culture.
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Affiliation(s)
- G G LaRochelle
- Department of Anatomy, Ohio State University, College of Medicine, Columbus 43210
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22
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Blackman MA, Marrack P, Kappler J. Influence of the major histocompatibility complex on positive thymic selection of V beta 17a+ T cells. Science 1989; 244:214-7. [PMID: 2784868 DOI: 10.1126/science.2784868] [Citation(s) in RCA: 92] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
A monoclonal antibody was used to show directly positive thymic selection of the T cell repertoire in mouse strains expressing the 17a beta-chain variable domain (V beta 17a) of the T cell receptor. In the absence of the potent tolerizing class II major histocompatibility complex (MHC) molecule, I-E, peripheral expression of V beta 17a+ T cell receptors varied with the MHC haplotype of the mouse strain. In the most extreme case, H-2q mice expressed high peripheral levels of CD4+ V beta 17a+ T cells (14 to 19 percent), whereas H-2b mice expressed low levels (3 to 4 percent). Analysis of (b x q)F1 mice and chimeric mice showed that these differences were determined by positive thymic selection and implicated the thymic epithelium as the controlling cell type.
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Affiliation(s)
- B J Fowlkes
- Laboratory of Cellular and Molecular Immunology, National Institute of Allergy and Infectious Diseases, Bethesda, Maryland 20892
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24
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Roncarolo MG, Yssel H, Touraine JL, Bacchetta R, Gebuhrer L, De Vries JE, Spits H. Antigen recognition by MHC-incompatible cells of a human mismatched chimera. J Exp Med 1988; 168:2139-52. [PMID: 2462006 PMCID: PMC2189142 DOI: 10.1084/jem.168.6.2139] [Citation(s) in RCA: 61] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Tetanus toxin (TT)-specific T cell clones of donor origin were obtained from a patient with severe combined immunodeficiency (SCID) successfully reconstituted by transplantation of allogeneic fetal liver and thymus cells from two different donors performed 10 yr ago. A series of these clones recognized TT in the context of "allo" class II HLA determinants expressed by recipient APC. The restriction element of two T cell clones with the HLA phenotype of the first donor (HLA-DR1,8) and one T cell clone with the HLA phenotype of the second transplant (HLA-DR3,9) was HLA-DR4 of the recipient, whereas other T cell clones derived from the second transplant recognized TT in the context of HLA-DR5 of the recipient's APC. These latter T cell clones were not able to proliferate in response to TT when autologous APC were used. These data demonstrate that recipient and donor cells having different HLA phenotypes could cooperate across the allogeneic barrier and that MHC restriction of antigen (Ag) recognition is independent from the MHC genotype of the T cells but is influenced by the environment in which the T cells mature. We also isolated T cell clones that were able to recognize processed TT presented by all allogeneic EBV cell lines tested, indicating that the Ag specificity of these clones was not restricted by a particular class II MHC molecule. The Ag-specific proliferative response of one of these clones could be blocked by anti-class II MHC mAbs. These results demonstrate that in addition to Ag recognition in the context of specific class II MHC Ags, other types of Ag-specific responses may occur in this human chimera. It is not clear whether this "allo" plus Ag recognition is the result of education of transplanted fetal cells in the host thymus. Taking into consideration our previous findings indicating that alloreactive T cell clones specific for the recipient cells could be isolated in vitro from the PBL of the same patient, our data suggest that the mechanism for deletion of self-reactive clones and the generation of MHC-restricted responses are different.
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Affiliation(s)
- M G Roncarolo
- UNICET, Laboratories for Immunological Research, Dardilly, France
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25
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Matis LA, Ezquerra A, Coligan JE. Expression of two distinct T cell receptor alpha/beta heterodimers by an antigen-specific T cell clone. J Exp Med 1988; 168:2379-84. [PMID: 2848922 PMCID: PMC2189151 DOI: 10.1084/jem.168.6.2379] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
A cytochrome c-specific, MHC-restricted T cell clone with two complete rearrangements of the same V beta 1 gene element was shown to express two different TCR alpha/beta heterodimers. Antipeptide antisera specific for TCR C beta 1 and C beta 2 peptides each immunoprecipitated distinct disulfide-linked cell surface heterodimers. The clone was derived from immunized allogeneic chimeric mice, and displayed multiple Ia specificities, including the ability to recognize antigen in association with both I-Ek and I-Es Ia molecules, as well as alloreactivity to the I-Eb molecule. It will be important to determine whether each receptor contributes independently to the overall specificity of the clone.
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Affiliation(s)
- L A Matis
- Division of Biochemistry and Biophysics, Food and Drug Administration, Bethesda, Maryland
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26
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Matis LA, Heckford SE, Longo DL. Influence of bone marrow-derived Ia-bearing cells on the selection of the T-cell repertoire. Immunol Res 1988; 7:329-38. [PMID: 3265713 DOI: 10.1007/bf02935537] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
We have presented the results of studies using chimeric animals to examine the role of distinct cell subsets in shaping the TCR repertoire. Examination of specificity and TCR expression in antigen-specific long-term T-cell lines derived from these chimeras suggests that bone marrow-derived APC play a role in the selection of T cells for MHC restriction during development, and also profoundly influence the expansion of the TCR repertoire following antigen priming. An understanding of the molecular mechanisms that govern TCR repertoire maturation may await the development of effective in vitro model systems of T-cell differentiation.
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Affiliation(s)
- L A Matis
- Division of Biochemistry and Biophysics, Food and Drug Administration
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27
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Sinha AA, Brautbar C, Szafer F, Friedmann A, Tzfoni E, Todd JA, Steinman L, McDevitt HO. A newly characterized HLA DQ beta allele associated with pemphigus vulgaris. Science 1988; 239:1026-9. [PMID: 2894075 DOI: 10.1126/science.2894075] [Citation(s) in RCA: 194] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The inheritance of particular alleles of major histocompatibility complex class II genes increases the risk for various human autoimmune diseases; however, only a small percentage of individuals having an allele associated with susceptibility develop disease. The identification of allelic variants more precisely correlated with disease susceptibility would greatly facilitate clinical screening and diagnosis. Oligonucleotide-primed gene amplification in vitro was used to determine the nucleotide sequence of a class II variant found almost exclusively in patients with the autoimmune skin disease pemphigus vulgaris. In addition to clinical implications, the disease-restricted distribution of this variant should provide insight into the molecular mechanisms underlying associations between diseases and HLA-class II genes.
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Affiliation(s)
- A A Sinha
- Department of Medical Microbiology, Stanford University, CA 94305
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Duijvestijn AM, Murawska MB, Meedendorp B, Klatter FA, Kampinga J, Nieuwenhuis P. Kinetics of rat thymic dendritic cells in bone marrow-reconstituted radiation chimeras. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 1988; 237:277-83. [PMID: 3075850 DOI: 10.1007/978-1-4684-5535-9_42] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Affiliation(s)
- A M Duijvestijn
- Department of Histology, Medical Faculty, University Groningen, The Netherlands
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Affiliation(s)
- J Sprent
- Department of Immunology, IMM4A, Research Institute of Scripps Clinic, La Jolla, California 92037
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30
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Schuurman HJ, Tielen FJ, Vaessen LM, Vos JG, Rozing J. Allogeneic cultured thymic fragments in congenitally athymic (nude) rats. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 1988; 237:285-92. [PMID: 3075851 DOI: 10.1007/978-1-4684-5535-9_43] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Affiliation(s)
- H J Schuurman
- Department of Internal Medicine, University Hospital, Utrecht, The Netherlands
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31
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Zepp F, Cussler K, Mannhardt W, Schofer O, Schulte-Wissermann H. Intrathymic tolerance induction: determination of tolerance to class II major histocompatibility complex antigens in maturing T lymphocytes by a bone marrow-derived non-lymphoid thymus cell. Scand J Immunol 1987; 26:589-601. [PMID: 3501157 DOI: 10.1111/j.1365-3083.1987.tb02294.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Two new experimental approaches were established to analyse the influence of the thymus on tolerance induction to major histocompatibility complex (MHC) antigens: The aim of the first experiment was to perform successful transplantation of adult allogeneic thymus tissue into nude mice, an attempt that has been unsuccessful in the past. Tolerance for the MHC genotype of a prospective thymus graft recipient (A) was induced in mice of strain B by injection of (A X B) splenocytes during the neonatal period. Adult thymic tissue obtained from these allogeneic donors (B) were grafted into the nude mice of strain A. The allogeneic thymus was accepted by the nude mice and immunoreconstitution was achieved. Subsequently the recipients developed tolerance to the MHC antigens of the allogeneic thymus donor as proved by mixed lymphocyte cultures and the acceptance of skin grafts. The second experiment was designed to determine which Ia-positive thymic compartment participates in conferring tolerance to MHC antigens in maturing T lymphocytes. Chimaeric thymus grafts were created by transplantation of neonatal thymus (A) into allogeneic nude mice (B) for a period of 8 weeks. The graft was populated with host bone marrow-derived Ia antigen-positive cells. The chimaeric thymuses consisting of type A epithelium but populated with both type A and B lymphocytes and non-lymphoid cells (i.e. Ia-positive macrophages and dendritic cells), were newly transplanted into nude mice of strain A. The engraftment lead to immunological reconstitution and the nude mice acquired tolerance to the MHC antigens expressed by the allogeneic Ia-positive cells populating the chimaeric graft. Irradiation of the chimaeric thymus prior to transplantation allowed transplantation of chimaeric thymus devoid of living thymocytes but still populated with functionally intact Ia-positive non-lymphoid cells. Transplantation of irradiated chimaeric thymuses resulted in immunoreconstitution and induced exactly the same allotolerance pattern as described above. The results demonstrate that not thymus epithelial cells but a bone-marrow-derived non-lymphoid thymus cell, most likely the Ia-antigen-positive thymic macrophage of dendritic cell, is responsible for the induction of tolerance to MHC antigens in developing T lymphocytes.
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Affiliation(s)
- F Zepp
- Department of Pediatrics, University of Mainz, FRG
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32
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Affiliation(s)
- H Barthélémy
- Department of Dermatology, University Hospital St Etienne, St Priest en Jarez, France
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Schuurman HJ, Vaessen LM, Broekhuizen R, Brandt CJ, Holewijn MC, Vos JG, Rozing J. Implantation of cultured thymic fragments in congenitally athymic (nude) rats. Influx of lymphocytes and dendritic cells. Scand J Immunol 1987; 26:129-39. [PMID: 3498208 DOI: 10.1111/j.1365-3083.1987.tb02245.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
We studied the early events in athymic immunoincompetent rats after implantation with cultured thymic fragments (CTF) under the kidney capsule, with special emphasis on the settlement of lymphocytes and non-lymphoid RT1 class II elements. At 2 weeks after grafting, tissue under the kidney capsule comprises strands of keratin-positive epithelial cells from the graft, without immigrant cells. At 3 weeks, the CTF graft is populated with lymphocytes and with non-lymphoid RT1 class II-positive cells expressing the recipient haplotype (allogeneic combinations). Part of these cells bear determinants recognized by an anti-rat dendritic cell antibody. At 4 weeks the graft exhibits a completely restored thymic architecture. At the periphery, the first indications of T-cell competence generated after CTF implantation are observed 6 weeks after implantation. At 18 weeks, the peripheral thymus-dependent immune system is almost completely developed. This includes in vitro alloreactivity, even to the donor RT1 haplotype of the graft. But skin grafts of the allogeneic CTF donor haplotype are not rejected. Thus, a state of in vivo tolerance is induced under the influence of grafted epithelium, which is not due to a specific deletion of alloreactive cells. We conclude that CTF regain their original thymic architecture between 2 and 4 weeks after implantation in (allogeneic) athymic nude recipients, and that only after this restoration does peripheral thymus-dependent immune competence start to develop.
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Kast WM, Voordouw AC, Leupers T, Visser JW, Melief CJ. Thymic immune response gene function in radiation chimeras reconstituted with purified hemopoietic stem cells. Eur J Immunol 1987; 17:471-5. [PMID: 3106065 DOI: 10.1002/eji.1830170406] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Thymectomized (C57BL/6[B6] X bm1)F1 mice and thymectomized (B6 X bm12)F1 mice were engrafted with neonatal parental thymus of either B6 type [H-2b mouse, Sendai virus cytotoxic T cell (Tc) responder] or bm1 type (H-2Kb mutant, Sendai virus Tc nonresponder) and B6 type (H-Y Tc responder) or bm12 type (H-2 I-Ab mutant, H-Y Tc nonresponder), respectively. All mice were irradiated and reconstituted with highly purified syngeneic pluripotent hemopoietic stem cells. All types of thymus engraftment resulted in a restored T cell immunocompetence. The Tc reaction to Sendai virus in (B6 X bm1)F1 mice engrafted with both responder type B6 and nonresponder, type bm1 neonatal thymus allowed maturation of Sendai-specific, H-2Kb-restricted Tc. For the Tc reaction to H-Y, only responder type B6 thymus restored the Tc response, whereas this was not achieved with nonresponder type bm12 thymuses. We conclude from this study that in this radiation stem cell chimera system the radioresistant component of the thymus dictates major histocompatibility complex (MHC) specificity and immune response phenotype of T cells restricted to class II MHC molecules but not of T cells restricted to class I MHC molecules.
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35
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Affiliation(s)
- J Sprent
- Department of Immunology, Research Institute of Scripps Clinic, La Jolla, California 92037
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36
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Lo D, Ron Y, Sprent J. Induction of MHC-restricted specificity and tolerance in the thymus. Immunol Res 1986; 5:221-32. [PMID: 3553374 DOI: 10.1007/bf02919203] [Citation(s) in RCA: 69] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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