Changes of phagocytic and bactericidal activities of neutrophils in relation to age

ABSTRACT

In the present study, we estimated phagocytic activity and bactericidal activity of neutrophils in a number of healthy persons representing a wide range of ages from 21 to 92 years. Individuals suffering from any disorders known to compromise host defense system were excluded from the study. To confirm the normality of different biologic systems, each individual was subjected to thorough clinical examination and laboratory investigations. The individuals were classified according to age into three groups. Group I from 21 to 39 years, group II from 40 to 58 years and group III from 62-92 years. We demonstrated a highly significant age-related decline of the phagocytic and bactericidal activities of neutrophils. A significant negative correlation was detected between age and phagocytic function in group II only, and a significant positive correlation was demonstrated between phagocytic power and bactericidal activity in the same group. It could be concluded that some of the functional abilities of neutrophils including phagocytic and bactericidal activities, do decline with age. This finding could result in decreased effectiveness of non specific defense system in the aged population. Such in age-associated effect may explain at least partially, the increased liability of old persons to infectious diseases