WordNet

a belief that can guide behavior; "the architect has a theory that more is less"; "they killed him on the theory that dead men tell no tales"
a well-substantiated explanation of some aspect of the natural world; an organized system of accepted knowledge that applies in a variety of circumstances to explain a specific set of phenomena; "theories can incorporate facts and laws and tested hypothes
an assortment of things from which a choice can be made; "the store carried a large selection of shoes"
of or relating to a clone

PrepTutorEJDIC

〈C〉(…の)(学問的な)『理論』,学説《+of+名》 / 〈C〉〈U〉(…の実地に対する)『理論』《+of+名》 / 〈C〉(…という)『推測』,憶測;見解,孝え《+that節》
〈U〉《時にA~》『選ぶこと』,選抜,選出;(…から)選び出すこと《+『from』(『out of, among』)+『名』》 / 〈C〉(…から)『選び抜かれた人』(『物』);(…の)抜粋,選集《+『from』(『of』)+『名』》 / 〈C〉《単数形で》(商店などの)品揃え / 〈U〉淘汰(とうた):natural selection自然淘汰

Wikipedia preview

出典(authority):フリー百科事典『ウィキペディア（Wikipedia）』「2013/07/30 09:01:47」(JST)

wiki en

Clonal selection of lymphocytes: 1) A hematopoietic stem cell undergoes differentiation and genetic rearrangement to produce 2) immature lymphocytes with many different antigen receptors. Those that bind to 3) antigens from the body's own tissues are destroyed, while the rest mature into 4) inactive lymphocytes. Most of these will never encounter a matching 5) foreign antigen, but those that do are activated and produce 6) many clones of themselves.

The clonal selection hypothesis has become a widely accepted model for how the immune system responds to infection and how certain types of B and T lymphocytes are selected for destruction of specific antigens invading the body.^[1]

Four predictions of the clonal selection hypothesis[edit]

Each lymphocyte bears a single type of receptor with a unique specificity (by V(D)J recombination).
Receptor occupation is required for cell activation.
The differentiated effector cells derived from an activated lymphocyte will bear receptors of identical specificity as the parental cell.
Those lymphocytes bearing receptors for self molecules will be deleted at an early stage.

Early work[edit]

In 1954, Danish immunologist Niels Jerne put forward a hypothesis which stated that there is already a vast array of lymphocytes in the body prior to any infection. The entrance of an antigen into the body results in the selection of only one type of lymphocyte to match it and produce a corresponding antibody to destroy the antigen.^[2]

This selection of only one type of lymphocyte results in it being cloned or reproduced by the body extensively to ensure there are enough antibodies produced to inhibit and prevent infection.

Further work[edit]

Australian immunologist Frank Macfarlane Burnet with input from David W. Talmage worked on this model, and was the first to name it "clonal selection theory." Burnet explained immunological memory as the cloning of two types of lymphocyte. One clone acts immediately to combat infection whilst the other is longer lasting, remaining in the immune system for a long time, which results in immunity to that antigen. In 1958, Sir Gustav Nossal and Joshua Lederberg showed that one B cell always produces only one antibody, which was the first evidence for clonal selection theory.^[3]

Theories supported by clonal selection[edit]

Burnet and Peter Medawar worked together on understanding immunological tolerance, a phenomenon also explained by clonal selection. This is the organism’s ability to tolerate the introduction of cells without an immune response as long as this occurs early in the organism’s development. There are a vast number of lymphocytes occurring in the immune system ranging from cells which are tolerant of self tissue to cells which are not tolerant of self tissue. However, only cells that are tolerant to self tissue will survive the embryonic stage. If non-self tissue is introduced, the lymphocytes which develop will be the ones which included the non-self tissues as self tissue.

In 1959 Burnet proposed that under certain circumstances, tissues could be successfully transplanted into foreign recipients. This work has led to a much greater understanding of the immune system and also great advances in tissues transplantation. Burnet and Medawar shared the Nobel Prize for physiology and medicine in 1960.

In 1974 Niels Kaj Jerne proposed that the immune system functions as a network, that is regulated via interactions between the variable parts of lymphocytes and their secreted molecules. Immune network theory is firmly based on the concept of clonal selection. Jerne won the Nobel Prize for medicine or physiology in 1984, largely for his contributions to immune network theory.

References[edit]

^ Rajewsky, Klaus (1996). "Clonal selection and learning in the antibody system". Nature 381 (6585): 751–758. doi:10.1038/381751a0. ISSN 0028-0836.
^ Burnet, F. M. (1976). "A Modification of Jerne's Theory of Antibody Production using the Concept of Clonal Selection". CA: A Cancer Journal for Clinicians 26 (2): 119–121. doi:10.3322/canjclin.26.2.119. ISSN 0007-9235.
^ Nossal, G. J. V. & Lederberg, J. 1958. Antibody production by single cells. Nature 181:1419-1420

"Biology in Context - The Spectrum of Life" Authors, Peter Aubusson, Eileen Kennedy.
Forsdyke, D.R. 1995. The Origins of the Clonal Selection Theory of Immunity FASEB. Journal 9:164-66

External links[edit]

Animation of clonal selection from the Walter & Elisa Hall institute.

UpToDate Contents

全文を閲覧するには購読必要です。 To read the full text you will need to subscribe.

1. 着床前の男女生み分け技術 techniques for preimplantation sex selection
2. 心臓ペーシングのモード：名称および選択 modes of cardiac pacing nomenclature and selection
3. うつ病の成人に対する対人関係療法（IPT）：適応、理論基盤、一般概念と有効性 interpersonal psychotherapy ipt for depressed adults indications theoretical foundation general concepts and efficacy
4. 胆石症の非外科的治療のための患者選択 patient selection for the nonsurgical treatment of gallstone disease
5. 多発性骨髄腫の病理生物学 pathobiology of multiple myeloma

English Journal

Chronic lymphocytic leukemia (CLL): Could tolerance mechanisms be the origin of lymphoid neoplasms?

García Muñoz R1, Llorente L.
Immunology.Immunology.2014 Mar 20. doi: 10.1111/imm.12285. [Epub ahead of print]
Much evidence has accumulated supporting the idea that neoplasms, including those of a lymphoproliferative nature, are influenced by their environment (1). This evidence has come from the study of a range of conditions such as inflammation, bacterial and viral infection, endemic diseases, and auto-a
PMID 24645778

Transcription could be the key to the selection advantage of mitochondrial deletion mutants in aging.

Kowald A1, Kirkwood TB.
Proceedings of the National Academy of Sciences of the United States of America.Proc Natl Acad Sci U S A.2014 Feb 25;111(8):2972-7. doi: 10.1073/pnas.1314970111. Epub 2014 Feb 3.
The mitochondrial theory of aging is widely popular but confronted by several apparent inconsistencies. On the one hand, mitochondrial energy production is of central importance to the health and proper functioning of cells, and single-cell studies have shown that mtDNA deletion mutants accumulate i
PMID 24569805

Integrating B cell lineage information into statistical tests for detecting selection in Ig sequences.

Uduman M1, Shlomchik MJ, Vigneault F, Church GM, Kleinstein SH.
Journal of immunology (Baltimore, Md. : 1950).J Immunol.2014 Feb 1;192(3):867-74. doi: 10.4049/jimmunol.1301551. Epub 2013 Dec 27.
Detecting selection in B cell Ig sequences is critical to understanding affinity maturation and can provide insights into Ag-driven selection in normal and pathologic immune responses. The most common sequence-based methods for detecting selection analyze the ratio of replacement and silent mutation
PMID 24376267

Japanese Journal

種分化を取り入れた免疫システムの提案

市村匠,山口崇志
日本知能情報ファジィ学会ファジィシステムシンポジウム講演論文集 27(0), 110-110, 2011
人工免疫システムはクローン選択理論に基づいて開発されている．我々は免疫学的記憶として記憶細胞を導入した免疫学的記憶モデルを提案した．生物学的免疫の抗原に対し産生され，そのうち適した抗体を記憶することによって，類似した抗原に反応するという仕組みに基づいている．記憶プロセスでは学習が行われるが，ここでは抗体がすべての事例に正解するように学習が行われるのではない．データベースに含まれる事例を自動でいくつ …
NAID 130004591699

記憶細胞と増殖比率を考慮したClonal Selection Algorithmの提案と医療データベースの分類

市村匠,山口崇志,マッキンケネス・ジェームズ
日本知能情報ファジィ学会ファジィシステムシンポジウム講演論文集 26(0), 145-145, 2010
Burnetにより提案されたクローン選択理論に対し，GaoらはSomatic Hyper mutation と Recepter Editingの手法を取り入れた人工免疫システムを提案した．市村らはこれを分類問題に応用し，入力信号の状態といくつかのクラスに分け，それぞれに対して適応的に反応するアルゴリズムを，免疫学的記憶のメカニズムに着想を得て開発した．本論文では，記憶細胞と増殖の比率を考慮するこ …
NAID 130005035388

Proliferation of Antibody in Clonal Selection Algorithm with Immunological Memory Cell

, ,
SCIS & ISIS 2010(0), 1329-1334, 2010
… The clonal selection principle explains the basic features of an adaptive immune response to a antigenic stimulus. … This paper explains a computational implementation of the clonal selection principle that explicitly takes into account the affinity maturation of the immune response. …
NAID 130005019484