소개글
"나이와 면역"에 대한 내용입니다.목차
1. Introduction2. Effect of aging on T cell generation
3. Effects of aging on mature peripheral T-cell population
4. Factors contributing to thymic involution
5. Age-dependent changes of antigen processing and presentation
6. Effects of aging on B-cell generation
7. Effects of aging on peripheral B -cell
8. Effects of aging on memory B -cell
9. Summary
10. Reference
본문내용
우리도 모르는 사이에 우리들은 주위의 다양한 미생물들과 접해가며 살아가고 있다. 지금 이 순간에도 우리의 피부 및 장내에는 수많은 미생물들이 살아가고 있으며, 음식을 통해서 도 다양한 박테리아 및 미생물들이 들어오고 있다. 그러나 이렇게 다양한 미생물과 접해있으면서도 질병에 걸리지 않고 건강하게 살 수 있는 이유는 미생물들이 병원성이 없는 경우도 있지만, 대부분은 우리 몸의 면역체계에 의해서 병원균에 대해서 효과적으로 방어를 하고 있기 때문이다. 면역체계는 크게 innate immunity와 adaptive immunity로 나눌 수 있는데, innate immunity는 병원균에 감염된 뒤 바로 시작되는 면역체계로, 병원균을 인지하고, 이러한 병원균들이 효과적으로 증식하지 못하도록 방어를 하고, 제거한다. 그러나 만약 병원균들이 innate immunity에 의해 제거 되지 못할 경우에는 innate immunity는 좀 더 한단계 높은 adaptive immunity를 개시한다. Adaptive immunity는 antigen-specific lymphocyte를 이용하여 우리 몸속에서 병원균들을 효과적으로 제거한다. Adaptive immunity에서 중요한 역할을 하는 면역세포는 B-lymphocyte와 T-lymphocyte이다. 이들은 bone marrow에서 유래한 precursor로부터 각각 bone marrow와 thymus에서 발달과정을 거치게 된다(Figure1). 그런데 면역체계에서 중요한 이들 세포들의 기능이 꾸준히 유지되는 것이 아니라 다른 기관들과 마찬가지로 나이에 따라서 기능이 감소하게 된다. 이처럼 나이가 들어감에 따라서 병원균에 대한 방어능력이 감소하고 질병에 걸릴 확률이 증가되는데, 이러한 면역반응의 age-associated change를 immunosenescence라 한다.(Table1)참고 자료
F. T. Hakim & R. E. Gress. Immunosenescence: deficits in adaptive immunity in the elderly. Tissue Antigens. 2007 Sep:70(3):179-89.AL Gruver, LL Hudson, and GD Sempowski. Immunosenescence of ageing. J Pathol 2007:211:144–156.
L.C. Hawkley, J.T. Cacioppo. Stress and the aging immune system. Brain, Behavior, and Immunity. 2004:18:114–119.
Sempowski GD, Hale LP, Sundy JS, Massey JM, Koup RA,Douek DC, et al. Leukemia inhibitory factor, oncostatin M, IL-6, and stem cell factor mRNA expression in human thymusincreases with age and is associated with thymic atrophy.J Immunol 2000:164(4):2180-2187.
Eaton SM, Burns EM, Kusser K, Randall TD, Haynes L. Age-related defects in CD4 T cell cognate helper function lead to reductions in humoral responses. J Exp Med 2004:200:1613–.22.
Haynes L, Eaton SM, Burns EM, Randall TD, Swain SL. CD4 T cell memory derived from young naive cells functions well into old age, but memory generated from aged naive cells functions poorly. Proc Natl Acad Sci USA 2003:100:15053–8.
Frasca D, Nguyen D, Riley RL, Blomberg BB. Decreased E12 and/or E47 transcription factor activity in the bone marrow as well as in the spleen of aged mice. J Immunol 2003:170:719–6.
Stephan RP, Reilly CR, Witte PL. Impaired ability of bone marrow stromal cells to support B-lymphopoiesis with age. Blood 1998:91:75–8.
Mertsching E, Grawunder U, Meyer V, Rolink T, Ceredig R. Phenotypic and functional analysis of B lymphopoiesis in interleukin-7-transgenic mice: expansion of pro/pre-B cell number and persistence of B lymphocyte development in lymph nodes and spleen. Eur J Immunol 1996:26:28–3.
Ceredig R, Bosco N, Maye PN, Andersson J, Rolink A. In interleukin-7-transgenic mice, increasing B lymphopoiesis increases follicular but not marginal zone B cell numbers. Eur J Immunol 2003:33:2567–76.
Weksler ME, Szabo P. The effect of age on the B cell repertoire. J Clin Immunol 2000:20(4):240–49.
Whisler RL, Williams JW Jr, Newhouse YG. Human B cell proliferative responses during aging. Reduced RNA synthesis and DNA replication after signal transduction by surface immunoglobulins compared to B cell antigenic determinants CD20 and CD40. Mech Ageing Dev 1991:61(2):209–22.
Zheng B, Han S, Takahashi Y, Kelsoe G. Immunosenescence and germinal center reaction. Immunol Rev 1997:160:63–7.
Whisler RL, Grants IS. Age-related alterations in the activation and expression of phosphotyrosine kinases and protein kinase C (PKC) among human B cells. Mech Ageing Dev 1993:71(1–):31–6.
Yang X, Stedra J, Cerny J. Relative contribution of T and B cells to hypermutation and selection of the antibody repertoire in germinal centers of aged mice. J ExpMed 1996:183(3):959–70.
Naylor K, Li G, Vallejo AN et al. The influence of age on T cell generation and TCR diversity. J Immunol 2005:174:7446–52.
Johnson SA, Cambier JC. Ageing, autoimmunity and arthritis: senescence of the B cell compartment –implications for humoral immunity. Arthritis Res Ther 2004:6:131–9.
Lazuardi L, Jenewein B, Wolf AM et al. Age-related loss of naive T cells and dysregulation of T-cell/B-cell interactions in human lymph nodes. Immunology 2005: 114: 37–3.
Eaton SM, Burns EM, Kusser K, Randall TD, Haynes L. Age-related defects inCD4 T cell cognate helper function lead to reductions in humoral responses. J Exp Med 2004:200:1613–2.
Aydar Y, Balogh P, Tew JG, Szakal AK. Age-related depression of FDC accessory functions and CD21 ligand-mediated repair of co-stimulation. Eur J Immunol 2002:32:2817–6.
Chong Y, Ikematsu H, YamajiKet al. CD27(1) (memory) B cell decrease and apoptosis-resistant CD27(2) (naive) B cell increase in aged humans: implications for age-related peripheral B cell developmental disturbances. Int Immunol 2005:17:383–0.
Breitbart E, Wang X, Leka LS et al. Altered memory B-cell homeostasis in human aging. J Gerontol A Biol Sci Med Sci 2002:57:B304–1.