['The immune system changes with age. In this study we characterized immune changes by performing immunologic screening profiles on ageing individuals.', 'This study was performed at Akdeniz University, in the Faculty of Medicine, Department of Immunology. Healthy volunteers consisted of a younger group (22 donors) and an older group (45 individuals). All subjects had no serious health problems (i.e. chronic heart, lung, liver or immunological diseases) and were taking no prescribed medications. Flow cytometry analysis was used to evaluate CD3, CD4, CD8, CD16, CD19, CD28, CD40, CD45, CD56, CD80, CD86, CTLA-4 and ELISA for IL-1 beta, IL-2, IL-6, IL-10, IFN-gamma, TNF-alpha expression In addition, NK activity and induced cytokine expression (by bioassay and ELISA, respectively) were evaluated.', 'No statistical differences were observed between the two groups in expression of CD3, CD8, CD19, CD80, CD86, CD16, CD 56, or CD28. A higher frequency of expression of CD4, CTLA-4, CD40, and CD45 was seen in older subjects by comparison with younger subjects. Cytokine profiles expressed by stimulated monocytes and lymphocytes from the two groups showed no difference in IL-1 beta, IL-2, IL-6, IL-10, TNF-alpha, and IFN-gamma production levels.'] Are cD40 , CD45 CTLA-4 levels elevated in healthy older adults?