[Age-dependence of the cellular immune reaction in childhood. 1. Studies on healthy children and disease pictures with secondary modification of the immune apparatus (without leukoses and tumors)].

The dependence on age of the rates of transformation of lymphocytes is due not only to the different number and degree of maturity of lymph cells, but also to the macrophageal function as well as the feedback mechanism of specific and nonspecific defense reactions. Premature and newborn infants do not differ in their cellular immunoreactions. Between birth and the fifth year of life there is a continuous increase in the rates of transformation of lymphocytes. This increase in rates of transformation is less marked between the fifth and twelfth years of life, with the transformation rate leveling off as age increases. Tests made using nonspecific antigens showed the rate of transformation to decrease with further increasing age. Testing with histocompatibility antigens showed no influences whatsoever. A striking result were higher rates of transformation observed in children with virus infections. The evaluation of cellular immunoreactions subsequent to infections or immunization is an important parameter for the immune system.