Age correlation of alpha-2-macroglobulin levels in healthy subjects.

Groups of 336 female and 310 male subjects from the age of 11 years to 94 and 86 years respectively were examined by radial immunodiffusion for their alpha-2-macroglobulin ( A 2M ) levels. Both groups were subjected to regression analysis, using a third degree polynomial, and the equations of the curves giving the best fit for the observed distribution of the values in relation to age were computed. The implications of the results for biology and medicine are discussed.