WordNet

an electronic memory device; "a memory and the CPU form the central part of a computer to which peripherals are attached" (同)computer memory, storage, computer storage, store, memory board
the cognitive processes whereby past experience is remembered; "he can do it from memory"; "he enjoyed remembering his father" (同)remembering
the power of retaining and recalling past experience; "he had a good memory when he was younger" (同)retention, retentiveness, retentivity
something that is remembered; "search as he would, the memory was lost"
the area of cognitive psychology that studies memory processes; "he taught a graduate course on learning and memory"
small room in which a monk or nun lives (同)cubicle
a device that delivers an electric current as the result of a chemical reaction (同)electric cell
a room where a prisoner is kept (同)jail cell, prison cell
(biology) the basic structural and functional unit of all organisms; they may exist as independent units of life (as in monads) or may form colonies or tissues as in higher plants and animals
any small compartment; "the cells of a honeycomb"
a small unit serving as part of or as the nucleus of a larger political movement (同)cadre
the 20th letter of the Roman alphabet (同)t
a written proposal or reminder (同)memorandum, memoranda
a tough youth of 1950s and 1960s wearing Edwardian style clothes (同)Teddy boy

PrepTutorEJDIC

〈C〉〈U〉『記憶』[『力』] / 〈C〉『思い出』,思い出の人(物,事) / 〈U〉《the~》記憶している期間 / 〈C〉死後の名声
(刑務所の)『独房』;(修道院の)小さい独居室 / (ミツバチの)みつ房,巣穴 / 小さい部屋 / 『細胞』 / 電池 / 花粉室 / (共産党などの)細胞
tritiumの化学記号
メモ,覚え書き / (会社内などの)連絡メモ

Wikipedia preview

出典(authority):フリー百科事典『ウィキペディア（Wikipedia）』「2015/12/04 08:07:15」(JST)

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A lymphocyte is shown in the center of this picture

1. After the naive T cell (N) encounters an antigen it becomes activated and begins to proliferate (divide) into many clones or daughter cells.
2. Some of the T cell clones will differentiate into effector T cells (E) that will perform the function of that cell (e.g. produce cytokines in the case of helper T cells or invoke cell killing in the case of cytotoxic T cells).

3. Some of the cells will form memory T cells (M) that will survive in an inactive state in the host for a long period of time until they re-encounter the same antigen and reactivate.

Memory T cells are a subset of infection- as well as potentially cancer-fighting T cells (also known as a T lymphocyte) that have previously encountered and responded to their cognate antigen; thus, the term antigen-experienced T cell is often applied. Such T cells can recognize foreign invaders, such as bacteria or viruses, as well as cancer cells. Memory T cells have become "experienced" by having encountered antigen during a prior infection, encounter with cancer, or previous vaccination. At a second encounter with the invader, memory T cells can reproduce to mount a faster and stronger immune response than the first time the immune system responded to the invader. This behaviour is utilized in T lymphocyte proliferation assays, which can reveal exposure to specific antigens.

Sub-populations

Within the overall memory T cell population, at least three distinct subpopulations have been described and can be recognised by the differential expression of chemokine receptor CCR7 and L-selectin (CD62L).^[1]

Stem memory T_SCM cells, like naive cells, are CD45RO−, CCR7+, CD45RA+, CD62L+ (L-selectin), CD27+, CD28+ and IL-7Rα+, but they also express large amounts of CD95, IL-2Rβ, CXCR3, and LFA-1, and show numerous functional attributes distinctive of memory cells.^[2]

Central memory T_CM cells express L-selectin and the CCR7, they secrete IL-2, but not IFNγ or IL-4.

Effector memory T_EM cells, however, do not express L-selectin or CCR7 but produce effector cytokines like IFNγ and IL-4.

More recently, other sub-populations have been explored using co-stimulatory molecules CD27 and CD28 expression in addition to CCR7 and CD62L.^[3]

Function

Antigen-specific memory T cells against viruses or other microbial molecules can be found in both T_CM and T_EM subsets. Although most information is currently based on observations in the cytotoxic T cells (CD8-positive) subset, similar populations appear to exist for both the helper T cells (CD4-positive) and the cytotoxic T cells.

central memory (T_CM). The T_CM cells are thought to contain some properties associated with memory cells stem cells. T_CM display a capacity for self-renewal due to high levels of phosphorylation of an important transcription factor known as STAT5.^[4] In mice, T_CM cells have been shown to confer superior protection against viruses,^[5] bacteria,^[5] and cancer^[6] in several different model systems compared with T_EM cells.
two highly related effector memory sub-types, which strongly express genes for molecules essential to the cytotoxic function of CD8 T cells:
- effector memory (T_EM)
- effector memory RA (T_EMRA)

More recently, antigen-experienced CD8+ T cells with apparent self-renewal capabilities have been described in mice.^[7]^[8] This population, now termed stem cell memory (T_SCM), can be identified by the markers CD44(low)CD62L(high)CD122(high)sca-1(+) and are capable of generating T_CM and T_EM subsets while maintaining themselves. In preclinical studies, adoptively transferred T_SCM confer superior immunity compared with other T memory subsets.^[8] Whether such a population is found in humans is the subject of active investigation.

References

^ Sallusto F, Langenkamp A, Geginat J, Lanzavecchia A (2000). "Functional subsets of memory T cells identified by CCR7 expression". Curr. Top. Microbiol. Immunol. Current Topics in Microbiology and Immunology 251: 167–71. doi:10.1007/978-3-642-57276-0_21. ISBN 978-3-540-67569-3. PMID 11036772.
^ Gattinoni L1, Lugli E, Ji Y, Pos Z, Paulos CM, Quigley MF, Almeida JR, Gostick E, Yu Z, Carpenito C, Wang E, Douek DC, Price DA, June CH, Marincola FM, Roederer M, Restifo NP (September 2011). "A human memory T cell subset with stem cell-like properties". Nat Med. 17 (10): 1290–1297. doi:10.1038/nm.2446. PMID 21926977.
^ Okada R, Kondo T, Matsuki F, Takata H, Takiguchi M (September 2008). "Phenotypic classification of human CD4+ T cell subsets and their differentiation". Int. Immunol. 20 (9): 1189–1199. doi:10.1093/intimm/dxn075. PMID 18635582.
^ Willinger T, Freeman T, Hasegawa H, McMichael AJ, Callan MF (November 2005). "Molecular signatures distinguish human central memory from effector memory CD8 T cell subsets". Journal of Immunology 175 (9): 5895–903. doi:10.4049/jimmunol.175.9.5895. PMID 16237082.
^ ^a ^b Wherry EJ, Teichgräber V, Becker TC, et al. (March 2003). "Lineage relationship and protective immunity of memory CD8 T cell subsets". Nature Immunology 4 (3): 225–234. doi:10.1038/ni889. PMID 12563257.
^ Klebanoff CA, Gattinoni L, Torabi-Parizi P, et al. (July 2005). "Central memory self/tumor-reactive CD8+ T cells confer superior antitumor immunity compared with effector memory T cells". Proceedings of the National Academy of Sciences of the United States of America 102 (27): 9571–9576. doi:10.1073/pnas.0503726102. PMC 1172264. PMID 15980149.
^ Zhang Y, Joe G, Hexner E, Zhu J, Emerson SG (December 2005). "Host-reactive CD8+ memory stem cells in graft-versus-host disease". Nature Medicine 11 (12): 1299–1305. doi:10.1038/nm1326. PMID 16288282.
^ ^a ^b Gattinoni L, Zhong XS, Palmer DC, et al. (July 2009). "Wnt signaling arrests effector T cell differentiation and generates CD8+ memory stem cells". Nature Medicine 15 (7): 808–813. doi:10.1038/nm.1982. PMC 2707501. PMID 19525962.

External links

T-cell Group - Cardiff University

UpToDate Contents

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1. 適応細胞性免疫応答 the adaptive cellular immune response
2. 同種造血細胞移植後の免疫再構築のための戦略 strategies for immune reconstitution following allogeneic hematopoietic cell transplantation
3. 胎児および新生児における免疫細胞の発達 the development of immune cells in the fetus and neonate
4. BおよびTリンパ球の正常な発生 normal b and t lymphocyte development
5. 成人T細胞性白血病/リンパ腫の臨床症状、病理学的特徴、および診断 clinical manifestations pathologic features and diagnosis of adult t cell leukemia lymphoma

English Journal

Role of vitamin D in cytotoxic T lymphocyte immunity to pathogens and cancer.

Sarkar S1,2, Hewison M3, Studzinski GP4, Li YC5, Kalia V1,2.
Critical reviews in clinical laboratory sciences.Crit Rev Clin Lab Sci.2016 Apr;53(2):132-45. doi: 10.3109/10408363.2015.1094443. Epub 2015 Oct 19.
The discovery of vitamin D receptor (VDR) expression in immune cells has opened up a new area of research into immunoregulation by vitamin D, a niche that is distinct from its classical role in skeletal health. Today, about three decades since this discovery, numerous cellular and molecular targets
PMID 26479950

Engineering less immunogenic and antigenic FVIII proteins.

Pratt KP1.
Cellular immunology.Cell Immunol.2016 Mar;301:12-7. doi: 10.1016/j.cellimm.2015.10.008. Epub 2015 Nov 2.
The development of neutralizing antibodies against blood coagulation factor VIII (FVIII), referred to clinically as "inhibitors", is the most challenging and deleterious adverse event to occur following intravenous infusions of FVIII to treat hemophilia A. Inhibitors occlude FVIII surfaces that must
PMID 26566286

Mobilization without immune depletion fails to restore immunological tolerance or preserve beta cell function in recent onset type 1 diabetes.

Haller MJ1, Atkinson MA1,2, Wasserfall CH2, Brusko TM2, Mathews CE2, Hulme M3, Cintron M1, Shuster J4, McGrail K2, Posgai A2, Schatz D1.
Clinical and experimental immunology.Clin Exp Immunol.2016 Mar;183(3):350-7. doi: 10.1111/cei.12731. Epub 2015 Dec 7.
Granulocyte colony-stimulating factor (G-CSF) has been used to restore immune competence following chemoablative cancer therapy and to promote immunological tolerance in certain settings of autoimmunity. Therefore, we tested the potential of G-CSF to impact type 1 diabetes (T1D) progression in patie
PMID 26462724