Certified Professionals
نویسنده
چکیده
Although negative selection in the thymus and induction of anergy in the periphery have been widely accepted as mechanisms for controlling autoreactivity, much less attention has been devoted to the role of suppressor T cells in mediating dominant immunologic self-tolerance. In 1995, Sakaguchi et al. (1, 2) made the seminal observation that the transfer of CD4 ϩ T cells which had been depleted of the minor subpopulation (10%) of cells that coexpressed the IL-2 receptor (IL-2R) ␣-chain (CD25) to nu/nu recipients induced organ-specific autoimmune disease in the majority of recipients. Cotransfer of CD4 ϩ CD25 ϩ cells with the CD4 ϩ CD25 Ϫ cells prevented the development of disease. The CD4 ϩ CD25 ϩ population was also shown to be solely responsible for the prevention of autoimmunity observed after mice are thymectomized on the third day of life (3). Rapid progress in the analysis of the regulatory function of the CD4 ϩ CD25 ϩ T cell population was made by the development of in vitro model systems that mimicked the function of these cells in vivo (4–6). Although minor differences were observed in the results obtained by the different groups, it is widely accepted that these cells are both hyporesponsive and suppressive. Further studies demonstrated that the CD4 ϩ CD25 ϩ T cells act through an APC-independent mechanism (7, and unpublished observations). Induction of suppressor activity requires that the CD4 ϩ CD25 ϩ cells be activated through their TCR, but once activated , they suppress T cell activation in an antigen-independent manner without a requirement for reactivation through their TCR. Therefore, we proposed (4) that CD4 ϩ CD25 ϩ cells represent a unique lineage of CD4 ϩ T cells that function as " professional suppressor cells. " The publication in this issue of four papers dealing with different aspects of the function of CD4 ϩ CD25 ϩ T cells clearly indicates that they have now received their " professional certification. " CD4 ϩ CD25 ϩ T Cells Are Generated in the Thymus. Saoudi et al. (8) were the first to describe that potent T regulatory (Tr) cells were present in the thymus of the adult rat. PVG rats develop autoimmune diabetes after adult thymectomy and split-dose irradiation. Transfer of CD4 ϩ CD8 Ϫ thymocytes or CD4 ϩ CD45RC Ϫ peripheral T cells prevented the development of disease. Subsequently, CD4 ϩ CD25 ϩ T cells were identified in the mouse thymus …
منابع مشابه
The benefits of human resources certification
This study examines whether Human Resources (HR) certification is beneficial to HR professionals and organizations and explores the antecedents of HR certification. We surveyed 422 HR professionals from local chapters of the Society of Human Resources Management. The results indicated certified HR professionals received more pay (even after controlling for level of education and years of HR exp...
متن کاملLongitudinal Emergency Medical Technician Attributes and Demographic Study (LEADS) Design and Methodology.
OBJECTIVES The objective of this study is to describe the Longitudinal Emergency Medical Technician (EMT) Attributes and Demographic Study (LEADS) design, instrument development, pilot testing, sampling procedures, and data collection methodology. Response rates are provided, along with results of follow-up surveys of non-responders (NRs) and a special survey of Emergency Medical Services (EMS)...
متن کاملKnowledge of exercise prescription guidelines among certified exercise professionals.
This survey assessed the knowledge of the "Guidance for prescribing exercise" issued by the American College of Sports Medicine (ACSM) in 2011 among certified exercise professionals. A sample of 1,808 certified exercise professionals (66.70% women, mean (± SD) age = 38.28 ± 12.56 years) responded to electronic invitations. The 11-question online questionnaire assessed knowledge of the recommend...
متن کاملCertified tactical paramedic: a benchmark for competency in austere and hostile environments.
متن کامل
Viral hepatitis as an occupational disease in Poland
BACKGROUND In medical terms, occupational diseases are defined as health disorders specifically associated with the working environment of people and their occupational activity. From the medical and legal perspectives, the vast majority of European countries consider particular diseases to be of occupational origin if they are mentioned in the current list of occupational diseases and caused b...
متن کاملCan certified health professionals treat obesity in a community-based programme? A quasi-experimental study
OBJECTIVE To test the effectiveness of a non-pharmaceutical programme for obese participants in a rural Eastern Canadian Province using certified health professionals. DESIGN A prospective quasi-experimental design with repeated premeasure and postmeasure. PARTICIPANTS 146 participants with obesity (body mass index >30 kg/m(2)) from rural and urban communities in an Eastern Canadian Provinc...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- The Journal of Experimental Medicine
دوره 193 شماره
صفحات -
تاریخ انتشار 2001