Researchers have made progress in recent years in identifying and understanding the mechanisms of decay and inefficiency in the aging immune system. Here, 50connect.co.uk looks at other threads in this work: "the most abundant form of white blood cells, whose job it is to defend against invading microbes, are only half as effective in people aged over 65 as they are in younger people ... What is particularly exciting about this finding is that in laboratory experiments we can improve the efficiency of white blood cells by adding DHEAS. We are now going to explore whether treating patients with this hormone can help them fight infections." Another study finds that "cells from older people had fewer receptors to direct the T lymphocytes to where they are needed, than younger people. This deficit resulted in less T lymphocytes reaching the infection site. ... older people have a specific immune response deficit in their skin, not necessarily a generalised lack of immunity."