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Zhou Q, Li H, Cheng Y, Ma X, Tang S, Tang C. Pax-8: Molecular biology, pathophysiology, and potential pathogenesis. Biofactors 2024; 50:408-421. [PMID: 37988248 DOI: 10.1002/biof.2016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/14/2023] [Accepted: 10/21/2023] [Indexed: 11/23/2023]
Abstract
Transcription factors, as the convergence points of multiple signaling pathways in eukaryotic cells, are closely involved in disease development. Pax-8, an important transcription factor belonging to the Pax family, exerts a crucial influence on the regulation of gene expression required for both physiological conditions and pathological processes. Pax-8 contributes to the pathogenesis of many human diseases, ranging from cardiovascular disease to many cancers, and therefore, it can be imagined that Pax-8 holds great therapeutic potential. In this review, we summarize the structure, distribution, function, and regulatory mechanisms of Pax-8 to provide a new research direction for Pax-8.
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Affiliation(s)
- Qinyi Zhou
- Institute of Cardiovascular Disease, Key Laboratory for Arteriosclerology of Hunan Province, Hunan International Scientific and Technological Cooperation Base of Arteriosclerotic Disease, Hengyang Medical School, University of South China, Hengyang, Hunan, China
- Department of Cardiology, The Affiliated Nanhua Hospital, Hengyang Medical School, University of South China, Hengyang, Hunan, China
| | - Heng Li
- Institute of Cardiovascular Disease, Key Laboratory for Arteriosclerology of Hunan Province, Hunan International Scientific and Technological Cooperation Base of Arteriosclerotic Disease, Hengyang Medical School, University of South China, Hengyang, Hunan, China
| | - Yaqiong Cheng
- Institute of Cardiovascular Disease, Key Laboratory for Arteriosclerology of Hunan Province, Hunan International Scientific and Technological Cooperation Base of Arteriosclerotic Disease, Hengyang Medical School, University of South China, Hengyang, Hunan, China
| | - Xiaofeng Ma
- Department of Cardiology, The Affiliated Nanhua Hospital, Hengyang Medical School, University of South China, Hengyang, Hunan, China
| | - Shilin Tang
- Department of Critical Care Medicine, the First Affiliated Hospital, Hengyang Medical School, University of South China, Hengyang, Hunan, China
| | - Chaoke Tang
- Institute of Cardiovascular Disease, Key Laboratory for Arteriosclerology of Hunan Province, Hunan International Scientific and Technological Cooperation Base of Arteriosclerotic Disease, Hengyang Medical School, University of South China, Hengyang, Hunan, China
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Yoshikawa G, Miyazaki K, Ogata H, Miyazaki M. The Evolution of Rag Gene Enhancers and Transcription Factor E and Id Proteins in the Adaptive Immune System. Int J Mol Sci 2021; 22:ijms22115888. [PMID: 34072618 PMCID: PMC8199221 DOI: 10.3390/ijms22115888] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2021] [Revised: 05/23/2021] [Accepted: 05/24/2021] [Indexed: 11/17/2022] Open
Abstract
Adaptive immunity relies on the V(D)J DNA recombination of immunoglobulin (Ig) and T cell receptor (TCR) genes, which enables the recognition of highly diverse antigens and the elicitation of antigen-specific immune responses. This process is mediated by recombination-activating gene (Rag) 1 and Rag2 (Rag1/2), whose expression is strictly controlled in a cell type-specific manner; the expression of Rag1/2 genes represents a hallmark of lymphoid lineage commitment. Although Rag genes are known to be evolutionally conserved among jawed vertebrates, how Rag genes are regulated by lineage-specific transcription factors (TFs) and how their regulatory system evolved among vertebrates have not been fully elucidated. Here, we reviewed the current body of knowledge concerning the cis-regulatory elements (CREs) of Rag genes and the evolution of the basic helix-loop-helix TF E protein regulating Rag gene CREs, as well as the evolution of the antagonist of this protein, the Id protein. This may help to understand how the adaptive immune system develops along with the evolution of responsible TFs and enhancers.
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Affiliation(s)
- Genki Yoshikawa
- Bioinformatics Center, Institute for Chemical Research, Kyoto University, Uji 611-0011, Japan;
| | - Kazuko Miyazaki
- Laboratory of Immunology, Institute for Frontier Life and Medical Sciences, Kyoto University, Kyoto 606-8507, Japan;
| | - Hiroyuki Ogata
- Bioinformatics Center, Institute for Chemical Research, Kyoto University, Uji 611-0011, Japan;
- Correspondence: (H.O.); (M.M.)
| | - Masaki Miyazaki
- Laboratory of Immunology, Institute for Frontier Life and Medical Sciences, Kyoto University, Kyoto 606-8507, Japan;
- Correspondence: (H.O.); (M.M.)
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Müller V, de Boer RJ, Bonhoeffer S, Szathmáry E. An evolutionary perspective on the systems of adaptive immunity. Biol Rev Camb Philos Soc 2017; 93:505-528. [PMID: 28745003 DOI: 10.1111/brv.12355] [Citation(s) in RCA: 59] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Revised: 06/28/2017] [Accepted: 06/30/2017] [Indexed: 12/22/2022]
Abstract
We propose an evolutionary perspective to classify and characterize the diverse systems of adaptive immunity that have been discovered across all major domains of life. We put forward a new function-based classification according to the way information is acquired by the immune systems: Darwinian immunity (currently known from, but not necessarily limited to, vertebrates) relies on the Darwinian process of clonal selection to 'learn' by cumulative trial-and-error feedback; Lamarckian immunity uses templated targeting (guided adaptation) to internalize heritable information on potential threats; finally, shotgun immunity operates through somatic mechanisms of variable targeting without feedback. We argue that the origin of Darwinian (but not Lamarckian or shotgun) immunity represents a radical innovation in the evolution of individuality and complexity, and propose to add it to the list of major evolutionary transitions. While transitions to higher-level units entail the suppression of selection at lower levels, Darwinian immunity re-opens cell-level selection within the multicellular organism, under the control of mechanisms that direct, rather than suppress, cell-level evolution for the benefit of the individual. From a conceptual point of view, the origin of Darwinian immunity can be regarded as the most radical transition in the history of life, in which evolution by natural selection has literally re-invented itself. Furthermore, the combination of clonal selection and somatic receptor diversity enabled a transition from limited to practically unlimited capacity to store information about the antigenic environment. The origin of Darwinian immunity therefore comprises both a transition in individuality and the emergence of a new information system - the two hallmarks of major evolutionary transitions. Finally, we present an evolutionary scenario for the origin of Darwinian immunity in vertebrates. We propose a revival of the concept of the 'Big Bang' of vertebrate immunity, arguing that its origin involved a 'difficult' (i.e. low-probability) evolutionary transition that might have occurred only once, in a common ancestor of all vertebrates. In contrast to the original concept, we argue that the limiting innovation was not the generation of somatic diversity, but the regulatory circuitry needed for the safe operation of amplifiable immune responses with somatically acquired targeting. Regulatory complexity increased abruptly by genomic duplications at the root of the vertebrate lineage, creating a rare opportunity to establish such circuitry. We discuss the selection forces that might have acted at the origin of the transition, and in the subsequent stepwise evolution leading to the modern immune systems of extant vertebrates.
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Affiliation(s)
- Viktor Müller
- Parmenides Center for the Conceptual Foundations of Science, 82049 Pullach/Munich, Germany.,Department of Plant Systematics, Ecology and Theoretical Biology, Institute of Biology, Eötvös Loránd University, 1117 Budapest, Hungary.,Evolutionary Systems Research Group, MTA Centre for Ecological Research, 8237 Tihany, Hungary
| | - Rob J de Boer
- Theoretical Biology, Department of Biology, Utrecht University, 3584 CH Utrecht, The Netherlands
| | - Sebastian Bonhoeffer
- Institute of Integrative Biology, Department of Environmental Systems Science, ETH Zurich, 8092 Zurich, Switzerland
| | - Eörs Szathmáry
- Parmenides Center for the Conceptual Foundations of Science, 82049 Pullach/Munich, Germany.,Department of Plant Systematics, Ecology and Theoretical Biology, Institute of Biology, Eötvös Loránd University, 1117 Budapest, Hungary.,Evolutionary Systems Research Group, MTA Centre for Ecological Research, 8237 Tihany, Hungary
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4
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Song X, Wang H, Chen H, Sun M, Liang Z, Wang L, Song L. Conserved hemopoietic transcription factor Cg-SCL delineates hematopoiesis of Pacific oyster Crassostrea gigas. FISH & SHELLFISH IMMUNOLOGY 2016; 51:180-188. [PMID: 26915307 DOI: 10.1016/j.fsi.2016.02.023] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2015] [Revised: 02/13/2016] [Accepted: 02/18/2016] [Indexed: 06/05/2023]
Abstract
Hemocytes are the effective immunocytes in bivalves, which have been reported to be derived from stem-like cells in gill epithelium of oyster. In the present work, a conserved haematopoietic transcription factor Tal-1/Scl (Stem Cell Leukemia) was identified in Pacific oyster (Cg-SCL), and it was evolutionarily close to the orthologs in deuterostomes. Cg-SCL was highly distributed in the hemocytes as well as gill and mantle. The hemocyte specific genes Integrin, EcSOD and haematopoietic transcription factors GATA3, C-Myb, c-kit, were down-regulated when Cg-SCL was interfered by dsRNA. During the larval developmental stages, the mRNA transcripts of Cg-SCL gradually increased after fertilization and peaked at early trochophore larvae stage (10 hpf, hours post fertilization), then sharply decreased in late trochophore larvae stage (15 hpf) before resuming in umbo larvae (120 hpf). Whole-mount immunofluorescence assay further revealed that the immunoreactivity of Cg-SCL appeared in blastula larvae with two approximate symmetric spots, and this expression pattern lasted in gastrula larvae. By trochophore, the immunoreactivity formed a ring around the dorsal region and then separated into two remarkable spots at the dorsal side in D-veliger larvae. After bacterial challenge, the mRNA expression levels of Cg-SCL were significantly up-regulated in the D-veliger and umbo larvae, indicating the available hematopoietic regulation in oyster larvae. These results demonstrated that Cg-SCL could be used as haematopoietic specific marker to trace potential developmental events of hematopoiesis during ontogenesis of oyster, which occurred early in blastula stage and maintained until D-veliger larvae.
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Affiliation(s)
- Xiaorui Song
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Hao Wang
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China
| | - Hao Chen
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Mingzhe Sun
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China
| | - Zhongxiu Liang
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China
| | - Lingling Wang
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China
| | - Linsheng Song
- Key Laboratory of Mariculture & Stock Enhancement in North China's Sea, Ministry of Agriculture, Dalian Ocean University, Dalian 116023, China.
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Im SP, Lee JS, Kim SW, Yu JE, Kim YR, Kim J, Lee JH, Jung TS. Investigation of variable lymphocyte receptors in the alternative adaptive immune response of hagfish. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2016; 55:203-210. [PMID: 26449649 DOI: 10.1016/j.dci.2015.10.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/21/2015] [Revised: 10/01/2015] [Accepted: 10/01/2015] [Indexed: 06/05/2023]
Abstract
Jawless vertebrates have an alternative adaptive immune system mediated by variable lymphocyte receptors (VLRs), VLRA, VLRC and VLRB. In investigation on the adaptive immunity of hagfish, avian influenza virus hemagglutinin (H9N2-HA1) was used as a model antigen, with mRNA expression levels of VLRA, VLRC and Ikaros were up-regulated in the first week post-immunization. CD45 was up-regulated after the first week; and expression of VLRB progressively increased over the course of the trial. The transcriptional/translational activation of VLRB in blood was verified. The VLRBs cloned from these transcripts showed diversity in their leucine-rich repeats (LRRs). The production of specific VLRB increased in a time- and dose-dependent manner, detected by an anti-VLRB antibody (11G5). The plasma VLRB could distinguish H9N2-HA1 from unrelated proteins, but not from other HA1 subtypes. Together, our findings show that VLRs play a major role in the alternative adaptive immune system of hagfish by responding to specific foreign substances, such as H9N2-HA1.
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Affiliation(s)
- Se Pyeong Im
- Laboratory of Aquatic Animal Diseases, Institute of Animal Medicine, College of Veterinary Medicine, Gyeongsang National University, Jinju, 660-701, Republic of Korea
| | - Jung Seok Lee
- Laboratory of Aquatic Animal Diseases, Institute of Animal Medicine, College of Veterinary Medicine, Gyeongsang National University, Jinju, 660-701, Republic of Korea
| | - Si Won Kim
- Laboratory of Aquatic Animal Diseases, Institute of Animal Medicine, College of Veterinary Medicine, Gyeongsang National University, Jinju, 660-701, Republic of Korea
| | - Jong Earn Yu
- Laboratory of Aquatic Animal Diseases, Institute of Animal Medicine, College of Veterinary Medicine, Gyeongsang National University, Jinju, 660-701, Republic of Korea
| | - Young Rim Kim
- Laboratory of Aquatic Animal Diseases, Institute of Animal Medicine, College of Veterinary Medicine, Gyeongsang National University, Jinju, 660-701, Republic of Korea
| | - Jaesung Kim
- Laboratory of Aquatic Animal Diseases, Institute of Animal Medicine, College of Veterinary Medicine, Gyeongsang National University, Jinju, 660-701, Republic of Korea
| | - Jeong-Ho Lee
- Inland Aquaculture Research Center, NFRDI, Changwon, 645-806, Republic of Korea
| | - Tae Sung Jung
- Laboratory of Aquatic Animal Diseases, Institute of Animal Medicine, College of Veterinary Medicine, Gyeongsang National University, Jinju, 660-701, Republic of Korea.
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Das S, Li J, Hirano M, Sutoh Y, Herrin BR, Cooper MD. Evolution of two prototypic T cell lineages. Cell Immunol 2015; 296:87-94. [PMID: 25958271 DOI: 10.1016/j.cellimm.2015.04.007] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2015] [Revised: 04/14/2015] [Accepted: 04/24/2015] [Indexed: 01/06/2023]
Abstract
Jawless vertebrates, which occupy a unique position in chordate phylogeny, employ leucine-rich repeat (LRR)-based variable lymphocyte receptors (VLR) for antigen recognition. During the assembly of the VLR genes (VLRA, VLRB and VLRC), donor LRR-encoding sequences are copied in a step-wise manner into the incomplete germ-line genes. The assembled VLR genes are differentially expressed by discrete lymphocyte lineages: VLRA- and VLRC-producing cells are T-cell like, whereas VLRB-producing cells are B-cell like. VLRA(+) and VLRC(+) lymphocytes resemble the two principal T-cell lineages of jawed vertebrates that express the αβ or γδ T-cell receptors (TCR). Reminiscent of the interspersed nature of the TCRα/TCRδ locus in jawed vertebrates, the close proximity of the VLRA and VLRC loci facilitates sharing of donor LRR sequences during VLRA and VLRC assembly. Here we discuss the insight these findings provide into vertebrate T- and B-cell evolution, and the alternative types of anticipatory receptors they use for adaptive immunity.
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Affiliation(s)
- Sabyasachi Das
- Emory Vaccine Center and Department of Pathology and Laboratory Medicine, Emory University, 1462 Clifton Road North-East, Atlanta, GA 30322, United States
| | - Jianxu Li
- Emory Vaccine Center and Department of Pathology and Laboratory Medicine, Emory University, 1462 Clifton Road North-East, Atlanta, GA 30322, United States
| | - Masayuki Hirano
- Emory Vaccine Center and Department of Pathology and Laboratory Medicine, Emory University, 1462 Clifton Road North-East, Atlanta, GA 30322, United States
| | - Yoichi Sutoh
- Emory Vaccine Center and Department of Pathology and Laboratory Medicine, Emory University, 1462 Clifton Road North-East, Atlanta, GA 30322, United States
| | - Brantley R Herrin
- Emory Vaccine Center and Department of Pathology and Laboratory Medicine, Emory University, 1462 Clifton Road North-East, Atlanta, GA 30322, United States
| | - Max D Cooper
- Emory Vaccine Center and Department of Pathology and Laboratory Medicine, Emory University, 1462 Clifton Road North-East, Atlanta, GA 30322, United States.
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Miz-1 regulates translation of Trp53 via ribosomal protein L22 in cells undergoing V(D)J recombination. Proc Natl Acad Sci U S A 2014; 111:E5411-9. [PMID: 25468973 DOI: 10.1073/pnas.1412107111] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
To be effective, the adaptive immune response requires a large repertoire of antigen receptors, which are generated through V(D)J recombination in lymphoid precursors. These precursors must be protected from DNA damage-induced cell death, however, because V(D)J recombination generates double-strand breaks and may activate p53. Here we show that the BTB/POZ domain protein Miz-1 restricts p53-dependent induction of apoptosis in both pro-B and DN3a pre-T cells that actively rearrange antigen receptor genes. Miz-1 exerts this function by directly activating the gene for ribosomal protein L22 (Rpl22), which binds to p53 mRNA and negatively regulates its translation. This mechanism limits p53 expression levels and thus contains its apoptosis-inducing functions in lymphocytes, precisely at differentiation stages in which V(D)J recombination occurs.
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8
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Foundational concepts of cell fate conversion to the hematopoietic lineage. Curr Opin Genet Dev 2013; 23:585-90. [PMID: 23725798 DOI: 10.1016/j.gde.2013.04.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2013] [Accepted: 04/05/2013] [Indexed: 12/20/2022]
Abstract
Direct conversion of cellular fate provides a potential approach to generate cells of the hematopoietic lineage without the requisite reversion to a pluripotent state via somatic cell reprogramming. The utilization of this technology has enabled transcription factor-mediated conversion of somatic cell types to primitive and mature hematopoietic cells. Recent studies demonstrate that the direct conversion of somatic cells to the hematopoietic lineage likely requires the use of pioneer transcription factors to establish an accessible chromatin state that is responsive to enforced expression of hematopoietic-specific transcription factors, in combination with appropriate culture conditions that facilitate reprogramming. Developing adaptable, experimental strategies that incorporate these parameters should enable the efficient generation of human hematopoietic cells with translational potential.
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Wang X, Werneck MBF, Wilson BG, Kim HJ, Kluk MJ, Thom CS, Wischhusen JW, Evans JA, Jesneck JL, Nguyen P, Sansam CG, Cantor H, Roberts CWM. TCR-dependent transformation of mature memory phenotype T cells in mice. J Clin Invest 2011; 121:3834-45. [PMID: 21926465 PMCID: PMC3195451 DOI: 10.1172/jci37210] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2011] [Accepted: 08/03/2011] [Indexed: 01/21/2023] Open
Abstract
A fundamental goal in cancer research is the identification of the cell types and signaling pathways capable of initiating and sustaining tumor growth, as this has the potential to reveal therapeutic targets. Stem and progenitor cells have been implicated in the genesis of select lymphoid malignancies. However, the identity of the cells in which mature lymphoid neoplasms are initiated remains unclear. Here, we investigate the origin of peripheral T cell lymphomas using mice in which Snf5, a chromatin remodelling-complex subunit with tumor suppressor activity, could be conditionally inactivated in developing T cells. In this model of mature peripheral T cell lymphomas, the cell of origin was a mature CD44hiCD122loCD8⁺ T cell that resembled a subset of memory cells that has capacity for self-renewal and robust expansion, features shared with stem cells. Further analysis showed that Snf5 loss led to activation of a Myc-driven signaling network and stem cell transcriptional program. Finally, lymphomagenesis and lymphoma proliferation depended upon TCR signaling, establishing what we believe to be a new paradigm for lymphoid malignancy growth. These findings suggest that the self-renewal and robust proliferative capacities of memory T cells are associated with vulnerability to oncogenic transformation. Our findings further suggest that agents that impinge upon TCR signaling may represent an effective therapeutic modality for this class of lethal human cancers.
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Affiliation(s)
- Xi Wang
- Department of Pediatric Oncology, Dana-Farber Cancer Institute, Boston, Massachusetts 02115, USA
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Ozcan A, Shen SS, Hamilton C, Anjana K, Coffey D, Krishnan B, Truong LD. PAX 8 expression in non-neoplastic tissues, primary tumors, and metastatic tumors: a comprehensive immunohistochemical study. Mod Pathol 2011; 24:751-64. [PMID: 21317881 DOI: 10.1038/modpathol.2011.3] [Citation(s) in RCA: 241] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
PAX 8 is a transcription factor that is essential for embryonic development of the kidney, Müllerian organs, and thyroid. It may also have a role in tumor development in these organs. The diagnostic utility of PAX 8 has not been comprehensively studied. Formalin-fixed, paraffin-embedded tissue samples for non-neoplastic tissues (n=1601), primary neoplasms (n=933), and metastatic neoplasms (n=496) were subjected to PAX 8 immunostain. In non-neoplastic tissues, PAX 8 was consistently noted in glomerular parietal epithelial cells, renal collecting ductal cells, atrophic renal tubular epithelial cells regardless of nephronic segments, and epithelial cells of the endocervix, endometrium, fallopian tube, seminal vesicle, epidydimis, thyroid, pancreatic islet cells, and lymphoid cells. PAX 8 was not seen in the rest of the tissue samples. In primary neoplasms, PAX 8 was expressed by 194 of 240 (89%) renal cell neoplasms, by 238 of 267 (89%) Müllerian-type neoplasms, by 65 of 65 (100%) thyroid follicular cell neoplasms, by 8 of 8 (100%) nephrogenic adenomas, and by 17 of 17 (100%) lymphomas. Weak focal staining was noted in 5 of 12 (42%) cases of parathyroid hyperplasia/adenoma and in 6 of 17 (35%) well-differentiated neuroendocrine tumors of the pancreas. PAX 8 was not seen in other neoplasms. In metastatic neoplasms, PAX 8 was expressed by 90 of 102 (88%) metastatic renal cell carcinomas, by 57 of 63 metastatic Müllerian tumors (90%), and by 6 of 6 metastatic papillary thyroid carcinomas (100%). There was also weak focal staining for 1 of 15 metastatic small cell carcinomas and for 1 of 9 metastatic well-differentiated neuroendocrine carcinomas. PAX 8 was not seen in other metastatic neoplasms. It can be successfully identified in routinely processed tissue samples, and its expression is mostly nuclear. PAX 8 expression in non-neoplastic mature tissues is limited to the organs, the embryonic development of which depends on this transcription factor. This tissue/cell-specific expression is maintained during both neoplastic transformation and metastasis. PAX 8 is a sensitive and specific marker for tumors of renal, Müllerian, or thyroid origin in both primary and metastatic sites.
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Affiliation(s)
- Ayhan Ozcan
- Departments of Pathology, The Methodist Hospital, Houston, TX 77030, USA
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Abstract
Approximately 500 million years ago, two types of recombinatorial adaptive immune systems (AISs) arose in vertebrates. The jawed vertebrates diversify their repertoire of immunoglobulin domain-based T and B cell antigen receptors mainly through the rearrangement of V(D)J gene segments and somatic hypermutation, but none of the fundamental AIS recognition elements in jawed vertebrates have been found in jawless vertebrates. Instead, the AIS of jawless vertebrates is based on variable lymphocyte receptors (VLRs) that are generated through recombinatorial usage of a large panel of highly diverse leucine-rich-repeat (LRR) sequences. Whereas the appearance of transposon-like, recombination-activating genes contributed uniquely to the origin of the AIS in jawed vertebrates, the use of activation-induced cytidine deaminase for receptor diversification is common to both the jawed and jawless vertebrates. Despite these differences in anticipatory receptor construction, the basic AIS design featuring two interactive T and B lymphocyte arms apparently evolved in an ancestor of jawed and jawless vertebrates within the context of preexisting innate immunity and has been maintained since as a consequence of powerful and enduring selection, most probably for pathogen defense purposes.
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Affiliation(s)
- Masayuki Hirano
- Emory Vaccine Center, Department of Pathology and Laboratory Medicine, Emory University, Atlanta, Georgia, USA
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Riveros C, Mellor D, Gandhi KS, McKay FC, Cox MB, Berretta R, Vaezpour SY, Inostroza-Ponta M, Broadley SA, Heard RN, Vucic S, Stewart GJ, Williams DW, Scott RJ, Lechner-Scott J, Booth DR, Moscato P. A transcription factor map as revealed by a genome-wide gene expression analysis of whole-blood mRNA transcriptome in multiple sclerosis. PLoS One 2010; 5:e14176. [PMID: 21152067 PMCID: PMC2995726 DOI: 10.1371/journal.pone.0014176] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2010] [Accepted: 10/20/2010] [Indexed: 12/03/2022] Open
Abstract
Background Several lines of evidence suggest that transcription factors are involved in the pathogenesis of Multiple Sclerosis (MS) but complete mapping of the whole network has been elusive. One of the reasons is that there are several clinical subtypes of MS and transcription factors that may be involved in one subtype may not be in others. We investigate the possibility that this network could be mapped using microarray technologies and contemporary bioinformatics methods on a dataset derived from whole blood in 99 untreated MS patients (36 Relapse Remitting MS, 43 Primary Progressive MS, and 20 Secondary Progressive MS) and 45 age-matched healthy controls. Methodology/Principal Findings We have used two different analytical methodologies: a non-standard differential expression analysis and a differential co-expression analysis, which have converged on a significant number of regulatory motifs that are statistically overrepresented in genes that are either differentially expressed (or differentially co-expressed) in cases and controls (e.g., V$KROX_Q6, p-value <3.31E-6; V$CREBP1_Q2, p-value <9.93E-6, V$YY1_02, p-value <1.65E-5). Conclusions/Significance Our analysis uncovered a network of transcription factors that potentially dysregulate several genes in MS or one or more of its disease subtypes. The most significant transcription factor motifs were for the Early Growth Response EGR/KROX family, ATF2, YY1 (Yin and Yang 1), E2F-1/DP-1 and E2F-4/DP-2 heterodimers, SOX5, and CREB and ATF families. These transcription factors are involved in early T-lymphocyte specification and commitment as well as in oligodendrocyte dedifferentiation and development, both pathways that have significant biological plausibility in MS causation.
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Affiliation(s)
- Carlos Riveros
- Centre for Bioinformatics, Biomarker Discovery & Information-Based Medicine, University of Newcastle, and Hunter Medical Research Institute, Newcastle, Australia
| | - Drew Mellor
- Centre for Bioinformatics, Biomarker Discovery & Information-Based Medicine, University of Newcastle, and Hunter Medical Research Institute, Newcastle, Australia
- School of Computer Science and Software Engineering, The University of Western Australia, Crawley, Australia
| | - Kaushal S. Gandhi
- Westmead Millennium Institute, University of Sydney, Westmead, Australia
| | - Fiona C. McKay
- Westmead Millennium Institute, University of Sydney, Westmead, Australia
| | - Mathew B. Cox
- Centre for Bioinformatics, Biomarker Discovery & Information-Based Medicine, University of Newcastle, and Hunter Medical Research Institute, Newcastle, Australia
- Hunter Medical Research Institute, Newcastle, Australia
| | - Regina Berretta
- Centre for Bioinformatics, Biomarker Discovery & Information-Based Medicine, University of Newcastle, and Hunter Medical Research Institute, Newcastle, Australia
| | - S. Yahya Vaezpour
- Centre for Bioinformatics, Biomarker Discovery & Information-Based Medicine, University of Newcastle, and Hunter Medical Research Institute, Newcastle, Australia
- Department of Computer Engineering, Amirkabir University of Technology, Tehran, Iran
| | - Mario Inostroza-Ponta
- Centre for Bioinformatics, Biomarker Discovery & Information-Based Medicine, University of Newcastle, and Hunter Medical Research Institute, Newcastle, Australia
- Departamento de Ingeniería Informática, Universidad de Santiago de Chile, Santiago, Chile
| | - Simon A. Broadley
- School of Medicine, Griffith University, Brisbane, Australia
- Department of Neurology, Gold Coast Hospital, Southport, Australia
| | - Robert N. Heard
- Westmead Millennium Institute, University of Sydney, Westmead, Australia
| | - Stephen Vucic
- Westmead Millennium Institute, University of Sydney, Westmead, Australia
| | - Graeme J. Stewart
- Westmead Millennium Institute, University of Sydney, Westmead, Australia
| | | | - Rodney J. Scott
- Centre for Bioinformatics, Biomarker Discovery & Information-Based Medicine, University of Newcastle, and Hunter Medical Research Institute, Newcastle, Australia
| | - Jeanette Lechner-Scott
- Centre for Bioinformatics, Biomarker Discovery & Information-Based Medicine, University of Newcastle, and Hunter Medical Research Institute, Newcastle, Australia
| | - David R. Booth
- Westmead Millennium Institute, University of Sydney, Westmead, Australia
| | - Pablo Moscato
- Centre for Bioinformatics, Biomarker Discovery & Information-Based Medicine, University of Newcastle, and Hunter Medical Research Institute, Newcastle, Australia
- Australian Research Council Centre of Excellence in Bioinformatics, St Lucia, Australia
- * E-mail:
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13
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Abstract
Adaptive immunity is mediated through numerous genetic and cellular processes that generate favourable somatic variants of antigen-binding receptors under evolutionary selection pressure by pathogens and other factors. Advances in our understanding of immunity in mammals and other model organisms are revealing the underlying basis and complexity of this remarkable system. Although the evolution of adaptive immunity has been thought to occur by the acquisition of novel molecular capabilities, an increasing amount of information from new model systems suggest that co-option and redirection of pre-existing systems are the main source of innovation. We combine evidence from a wide range of organisms to obtain an integrated view of the origins and patterns of divergence in adaptive immunity.
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Affiliation(s)
- Gary W Litman
- Department of Molecular Genetics, All Children's Hospital, St. Petersburg, Florida 33701, USA.
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14
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PAX-2 Expression in Non-neoplastic, Primary Neoplastic, and Metastatic Neoplastic Tissue. Appl Immunohistochem Mol Morphol 2010; 18:323-32. [PMID: 20216401 DOI: 10.1097/pai.0b013e3181d712ef] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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15
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Awakening lineage potential by Ikaros-mediated transcriptional priming. Curr Opin Immunol 2010; 22:154-60. [PMID: 20299195 DOI: 10.1016/j.coi.2010.02.011] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2010] [Accepted: 02/12/2010] [Indexed: 11/22/2022]
Abstract
Bioinformatic studies on a revised hierarchy of hematopoietic progenitors have provided a genome-wide view of lineage-affiliated transcriptional programs directing early hematopoiesis. Unexpectedly, lymphoid, myeloid, and erythroid gene expression programs were primed with similar frequency at the multipotent progenitor stage indicating a stochastic nature to this process. Multilineage transcriptional priming is quickly resolved upon erythroid lineage restriction with both lymphoid and myeloid transcriptional programs rapidly extinguished. However, expression of lymphoid and myeloid factors remains active past nominal lymphoid and myeloid lineage restrictions, revealing a common genetic network utilized by both pathways. Priming and resolution of multilineage potential is dependent on the activity of the DNA binding factor Ikaros. Ikaros primes the lymphoid transcriptional program in the HSC and represses the stem cell and other disparate transcriptional programs downstream of the HSC. Loss of Ikaros removes the lymphoid leg of the immune system and may confer aberrant self-renewing properties to myeloid progenitors.
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16
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Kasahara M. Genome duplication and T cell immunity. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2010; 92:7-36. [PMID: 20800811 DOI: 10.1016/s1877-1173(10)92002-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The adaptive immune system (AIS) mediated by T cells and B cells arose ~450 million years ago in a common ancestor of jawed vertebrates. This system was so successful that, once established, it has been maintained in all classes of jawed vertebrates with only minor modifications. One event thought to have contributed to the emergence of this form of AIS is two rounds of whole-genome duplication. This event enabled jawed vertebrate ancestors to acquire many paralogous genes, known as ohnologs, with essential roles in T cell and B cell immunity. Ohnologs encode the key components of the antigen presentation machinery and signal transduction pathway for lymphocyte activation as well as numerous transcription factors important for lymphocyte development. Recently, it has been discovered that jawless vertebrates have developed an AIS employing antigen receptors unrelated to T/B cell receptors, but with marked overall similarities to the AIS of jawed vertebrates. Emerging evidence suggests that a common ancestor of all vertebrates was equipped with T-lymphoid and B-lymphoid lineages.
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Affiliation(s)
- Masanori Kasahara
- Department of Pathology, Hokkaido, University Graduate School of Medicine, Sapporo, Japan
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17
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Large EE, Mathies LD. hunchback and Ikaros-like zinc finger genes control reproductive system development in Caenorhabditis elegans. Dev Biol 2009; 339:51-64. [PMID: 20026024 DOI: 10.1016/j.ydbio.2009.12.013] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2009] [Revised: 11/30/2009] [Accepted: 12/09/2009] [Indexed: 01/29/2023]
Abstract
Here we provide evidence for a C2H2 zinc finger gene family with similarity to Ikaros and hunchback. The founding member of this family is Caenorhabditis elegans ehn-3, which has important and poorly understood functions in somatic gonad development. We examined the expression and function of four additional hunchback/Ikaros-like (HIL) genes in C. elegans reproductive system development. Two genes, ehn-3 and R08E3.4, are expressed in somatic gonadal precursors (SGPs) and have overlapping functions in their development. In ehn-3; R08E3.4 double mutants, we find defects in the generation of distal tip cells, anchor cells, and spermatheca; three of the five tissues derived from the SGPs. We provide in vivo evidence that C. elegans HIL proteins have functionally distinct zinc finger domains, with specificity residing in the N-terminal set of four zinc fingers and a likely protein-protein interaction domain provided by the C-terminal pair of zinc fingers. In addition, we find that a chimeric human Ikaros protein containing the N-terminal zinc fingers of EHN-3 functions in C. elegans. Together, these results lend support to the idea that the C. elegans HIL genes and Ikaros have similar functional domains. We propose that hunchback, Ikaros, and the HIL genes arose from a common ancestor that was present prior to the divergence of protostomes and deuterostomes.
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Affiliation(s)
- Edward E Large
- Department of Genetics, North Carolina State University, 3510 Thomas Hall, Raleigh, NC 27695-7614, USA
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18
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Abstract
Strong evidence is emerging that the nervous and immune systems share mechanisms of gene regulation, signaling, cell communication, and supracellular organization. This brings to the fore many questions, not least of which is the developmental and evolutionary origin of the commonalities between the two systems. By providing answers to these questions, immunologists and neurobiologists increasingly expose the mechanistic and conceptual affinities of their respective fields and facilitate the understanding of fundamental principles that govern the organization of complex cellular systems. The current essay and reviews in Immunity and Neuron attempt to communicate to the wider scientific community a series of examples relating to commonalities between the immune and nervous system and enhance the dialog and exchange of ideas between the two fields.
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19
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John LB, Yoong S, Ward AC. Evolution of the Ikaros gene family: implications for the origins of adaptive immunity. THE JOURNAL OF IMMUNOLOGY 2009; 182:4792-9. [PMID: 19342657 DOI: 10.4049/jimmunol.0802372] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Members of the Ikaros family of transcription factors are important for immune system development. Analysis of Ikaros-related genes from a range of species suggests the Ikaros family derived from a primordial gene, possibly related to the present-day protostome Hunchback genes. This duplicated before the divergence of urochordates to produce two distinct lineages: one that generated the Ikaros factor-like (IFL) 2 genes of urochordates/lower vertebrates and the Pegasus genes of higher vertebrates, and one that generated the IFL1 genes of urochordates/lower vertebrates, the IKFL1 and IKFL2 genes of agnathans and the remaining four Ikaros members of higher vertebrates. Expansion of the IFL1 lineage most likely occurred via the two intervening rounds of whole genome duplication. A proposed third whole genome duplication in teleost fish produced a further increase in complexity of the gene family with additional Pegasus and Eos members. These findings question the use of IFL sequences as evidence for the existence of adaptive immunity in early chordates and vertebrates. Instead, this study is consistent with a later emergence of adaptive immunity coincident with the appearance of the definitive lymphoid markers Ikaros, Aiolos, and Helios.
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Affiliation(s)
- Liza B John
- Center for Cellular and Molecular Biology, School of Life and Environmental Sciences, Deakin University, Burwood, Victoria, Australia.
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20
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Genome-wide lineage-specific transcriptional networks underscore Ikaros-dependent lymphoid priming in hematopoietic stem cells. Immunity 2009; 30:493-507. [PMID: 19345118 DOI: 10.1016/j.immuni.2009.01.014] [Citation(s) in RCA: 190] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2008] [Revised: 12/17/2008] [Accepted: 01/26/2009] [Indexed: 10/20/2022]
Abstract
The mechanisms regulating lineage potential during early hematopoiesis were investigated. First, a cascade of lineage-affiliated gene expression signatures, primed in hematopoietic stem cells (HSCs) and differentially propagated in lineage-restricted progenitors, was identified. Lymphoid transcripts were primed as early as the HSC, together with myeloid and erythroid transcripts. Although this multilineage priming was resolved upon subsequent lineage restrictions, an unexpected cosegregation of lymphoid and myeloid gene expression and potential past a nominal myeloid restriction point was identified. Finally, we demonstrated that whereas the zinc finger DNA-binding factor Ikaros was required for induction of lymphoid lineage priming in the HSC, it was also necessary for repression of genetic programs compatible with self-renewal and multipotency downstream of the HSC. Taken together, our studies provide new insight into the priming and restriction of lineage potentials during early hematopoiesis and identify Ikaros as a key bivalent regulator of this process.
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21
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Hematopoietic fingerprints: an expression database of stem cells and their progeny. Cell Stem Cell 2008; 1:578-91. [PMID: 18371395 DOI: 10.1016/j.stem.2007.10.003] [Citation(s) in RCA: 260] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2007] [Revised: 07/04/2007] [Accepted: 10/09/2007] [Indexed: 12/15/2022]
Abstract
Hematopoietic stem cells (HSCs) continuously regenerate the hematologic system, yet few genes regulating this process have been defined. To identify candidate factors involved in differentiation and self-renewal, we have generated an expression database of hematopoietic stem cells and their differentiated progeny, including erythrocytes, granulocytes, monocytes, NK cells, activated and naive T cells, and B cells. Bioinformatic analysis revealed HSCs were more transcriptionally active than their progeny and shared a common activation mechanism with T cells. Each cell type also displayed unique biases in the regulation of particular genetic pathways, with Wnt signaling particularly enhanced in HSCs. We identified approximately 100-400 genes uniquely expressed in each cell type, termed lineage "fingerprints." In overexpression studies, two of these genes, Zfp 105 from the NK cell lineage, and Ets2 from the monocyte lineage, were able to significantly influence differentiation toward their respective lineages, demonstrating the utility of the fingerprints for identifying genes that regulate differentiation.
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22
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Enos ME, Bancos SA, Bushnell T, Crispe IN. E2F4 modulates differentiation and gene expression in hematopoietic progenitor cells during commitment to the lymphoid lineage. THE JOURNAL OF IMMUNOLOGY 2008; 180:3699-707. [PMID: 18322175 DOI: 10.4049/jimmunol.180.6.3699] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The E2F4 protein is involved in gene repression and cell cycle exit, and also has poorly understood effects in differentiation. We analyzed the impact of E2F4 deficiency on early steps in mouse hematopoietic development, and found defects in early hematopoietic progenitor cells that were propagated through common lymphoid precursors to the B and T lineages. In contrast, the defects in erythromyeloid precursor cells were self-correcting over time. This suggests that E2F4 is important in early stages of commitment to the lymphoid lineage. The E2F4-deficient progenitor cells showed reduced expression of several key lymphoid-lineage genes, and overexpression of two erythromyeloid lineage genes. However, we did not detect effects on cell proliferation. These findings emphasize the significance of E2F4 in controlling gene expression and cell fate.
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Affiliation(s)
- Megan E Enos
- Department of Microbiology and Immunology, David H Smith Center for Vaccine Biology and Immunology, University of Rochester, Rochester, NY 14620, USA
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23
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Amemiya CT, Saha NR, Zapata A. Evolution and development of immunological structures in the lamprey. Curr Opin Immunol 2007; 19:535-41. [PMID: 17875388 PMCID: PMC2093943 DOI: 10.1016/j.coi.2007.08.003] [Citation(s) in RCA: 81] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2007] [Revised: 08/06/2007] [Accepted: 08/06/2007] [Indexed: 01/11/2023]
Abstract
Comparative immunology has been revitalized by the integration of genomics approaches, which allow a foothold into addressing problems that previously had been difficult to study. One such problem had been the enigmatic finding of overt immune anatomical structures in the lamprey, yet its apparent lack of bona fide immunoglobulin or T cell receptor molecules. The genomic characterization of a novel extended locus that undergoes rearrangements to generate receptor diversity and the subsequent implementation of this diversity in the immune system of lampreys have generated considerable interest as well as new avenues for investigation. Here, we review the anatomical structures of the lamprey that exhibit lympho-hematopoietic characteristics, with the ultimate goal of reconciling these data with contemporary molecular findings. By integrating these datasets we seek to better understand how an alternative adaptive immune system could have evolved.
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Affiliation(s)
- Chris T Amemiya
- Molecular Genetics Program, Benaroya Research Institute at Virginia Mason, 1201 Ninth Avenue, Seattle, WA 98101, United States.
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24
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Abstract
At least three types of B lymphocytes are important for providing memory in a humoral immune response: 'classical' memory cells that do not secrete immunoglobulin (Ig), long-lived plasma cells (LLPCs) in the bone marrow, and 'innate-like' B-1 cells. In this review, our work on B-lymphocyte-induced maturation protein-1 (Blimp-1), a critical regulator of terminal B-cell differentiation, is discussed in the context of current knowledge of all transcriptional controls that regulate these three types of B cells. Blimp-1 is not required for formation of memory cells, but it is required for them to progress toward becoming plasma cells. Blimp-1 is required for Ig secretion in plasma cells and in B-1 cells. Induction of the activator X-box-binding protein-1 and formation of mu-secreted mRNA depend on Blimp-1 in both cell types. Finally, even after their formation, LLPCs in the bone marrow continue to require Blimp-1 for their maintenance.
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Affiliation(s)
- Kathryn Calame
- Department of Microbiology, Columbia University College of Physicians and Surgeons, New York, NY 10032, USA.
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25
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Hibino T, Loza-Coll M, Messier C, Majeske AJ, Cohen AH, Terwilliger DP, Buckley KM, Brockton V, Nair SV, Berney K, Fugmann SD, Anderson MK, Pancer Z, Cameron RA, Smith LC, Rast JP. The immune gene repertoire encoded in the purple sea urchin genome. Dev Biol 2006; 300:349-65. [PMID: 17027739 DOI: 10.1016/j.ydbio.2006.08.065] [Citation(s) in RCA: 422] [Impact Index Per Article: 23.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2006] [Revised: 08/21/2006] [Accepted: 08/28/2006] [Indexed: 01/01/2023]
Abstract
Echinoderms occupy a critical and largely unexplored phylogenetic vantage point from which to infer both the early evolution of bilaterian immunity and the underpinnings of the vertebrate adaptive immune system. Here we present an initial survey of the purple sea urchin genome for genes associated with immunity. An elaborate repertoire of potential immune receptors, regulators and effectors is present, including unprecedented expansions of innate pathogen recognition genes. These include a diverse array of 222 Toll-like receptor (TLR) genes and a coordinate expansion of directly associated signaling adaptors. Notably, a subset of sea urchin TLR genes encodes receptors with structural characteristics previously identified only in protostomes. A similarly expanded set of 203 NOD/NALP-like cytoplasmic recognition proteins is present. These genes have previously been identified only in vertebrates where they are represented in much lower numbers. Genes that mediate the alternative and lectin complement pathways are described, while gene homologues of the terminal pathway are not present. We have also identified several homologues of genes that function in jawed vertebrate adaptive immunity. The most striking of these is a gene cluster with similarity to the jawed vertebrate Recombination Activating Genes 1 and 2 (RAG1/2). Sea urchins are long-lived, complex organisms and these findings reveal an innate immune system of unprecedented complexity. Whether the presumably intense selective processes that molded these gene families also gave rise to novel immune mechanisms akin to adaptive systems remains to be seen. The genome sequence provides immediate opportunities to apply the advantages of the sea urchin model toward problems in developmental and evolutionary immunobiology.
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Affiliation(s)
- Taku Hibino
- Sunnybrook Research Institute and Department of Medical Biophysics, University of Toronto, 2075 Bayview Ave., Room S-126b, Toronto, Ontario, Canada M4N 3M5
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26
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Abstract
Approximately 500 mya two types of recombinatorial adaptive immune systems appeared in vertebrates. Jawed vertebrates generate a diverse repertoire of B and T cell antigen receptors through the rearrangement of immunoglobulin V, D, and J gene fragments, whereas jawless fish assemble their variable lymphocyte receptors through recombinatorial usage of leucine-rich repeat (LRR) modular units. Invariant germ line-encoded, LRR-containing proteins are pivotal mediators of microbial recognition throughout the plant and animal kingdoms. Whereas the genomes of plants and deuterostome and chordate invertebrates harbor large arsenals of recognition receptors primarily encoding LRR-containing proteins, relatively few innate pattern recognition receptors suffice for survival of pathogen-infected nematodes, insects, and vertebrates. The appearance of a lymphocyte-based recombinatorial system of anticipatory immunity in the vertebrates may have been driven by a need to facilitate developmental and morphological plasticity in addition to the advantage conferred by the ability to recognize a larger portion of the antigenic world.
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Affiliation(s)
- Zeev Pancer
- Center of Marine Biotechnology, University of Maryland Biotechnology Institute, Baltimore, Maryland 21202, USA.
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27
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Abstract
A clonally diverse anticipatory repertoire in which each lymphocyte bears a unique antigen receptor is the central feature of the adaptive immune system that evolved in our vertebrate ancestors. The survival advantage gained through adding this type of adaptive immune system to a pre-existing innate immune system led to the evolution of alternative ways for lymphocytes to generate diverse antigen receptors for use in recognizing and repelling pathogen invaders. All jawed vertebrates assemble their antigen-receptor genes through recombinatorial rearrangement of different immunoglobulin or T cell receptor gene segments. The surviving jawless vertebrates, lampreys and hagfish, instead solved the receptor diversification problem by the recombinatorial assembly of leucine-rich-repeat genetic modules to encode variable lymphocyte receptors. The convergent evolution of these remarkably different adaptive immune systems involved innovative genetic modification of innate-immune-system components.
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Affiliation(s)
- Max D Cooper
- Division of Developmental and Clinical Immunology, Departments of Medicine, Microbiology, Pediatrics, and Pathology, University of Alabama at Birmingham, Birmingham, AL 35294, USA.
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28
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Quinn WJ, Scholz JL, Cancro MP. Dwindling competition with constant demand: Can homeostatic adjustments explain age-associated changes in peripheral B cell selection? Semin Immunol 2005; 17:362-9. [PMID: 15970442 DOI: 10.1016/j.smim.2005.05.016] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The close relationship between specificity-based selection and homeostatic processes in maintaining peripheral B cell pools has become increasingly evident. Thus, age-associated changes observed within these pools may reflect homeostatic responses to proximal primary lesions. Marked shifts in the size and dynamics of most B lymphocyte subsets and their progenitors occur with age: perturbations in B lineage precursors result in reduced production of immature B lymphocytes in the bone marrow and transitional pools in the periphery, but these effects appear to be offset by compensatory homeostatic processes at the marrow-periphery interface. We propose a model whereby these "distal" homeostatic adjustments relax the stringency of specificity based selection, affording a potential explanation for the increased frequency of autoreactive specificities with age.
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Affiliation(s)
- William J Quinn
- University of Pennsylvania School of Medicine, Department of Pathology and Laboratory Medicine, 284 John Morgan Building, 36th And Hamilton Walk, Philadelphia, PA 19104-8062, USA
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29
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Abstract
Lymphocytes are ultimately derived from hematopoietic stem cells, however the intervening steps that give rise to lymphocyte progenitors are still under intense investigation. In particular, whether a common lymphocyte progenitor serves exclusively as a lymphoid precursor, or whether this cell retains limited myeloid progenitor potential are addressed by Rolink and colleagues. This issue is highlighted by their identification within the bone marrow of early progenitors with lymphoid and myeloid developmental potential or EPLMs. How these cells fit into our current understanding of lymphocyte development, and how this new subset helps to further refine our view of the common lymphocyte progenitor are discussed.
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