나이와 면역

소개

"나이와 면역"에 대한 내용입니다.

목차

1. Introduction
2. 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)

참고자료

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