Natural Killer Cell Activity and Other Immunologic Function in the Normal Elderly : an Assodiation with Infection

点击翻译按钮获取中文摘要

We examined natural killer (NK) cell activity (lytic units, LU) and lymphocyte subsets (CD3+, CD4+, CD8+, CD25+, CD56+, CD3+HLA・DR+, CD3+CD56+ and NK [CD3-CD56+] cells) in the immunologically normal elderly. Criteria for selection were the admission criteria for immunologerontological studies (Mech Ageing Dev 1984; 28: 47-55), a performance status of World Health Organization grade 2 or 3, and informed consent. The LU of one normal subject was determined concurrently in every NK cell activity assay to ascertain the reliability of the assays. Further, the LU of this subject was defined as 100, and the relative potency of LU of the examined subjects (corrected LU, CLU) was calculated. CLU of 108 subjects (83 females; 81 yeards old [SD 8, range 63-99]) was determined. We examined whether any of the predetermined parameters related to infectious episodes during the follow-up period. A lowr CLU, age over 75 years, performance status of 3, and serum albumin value less tha 3.5 g/dl correlated with the development of infection. Multivatiate logistic regression analysis showed that a lower NK cell activity was an independent predictor for the development of infection.