REPERTOIRES OF NATURAL AUTOANTIBODIES AGAINST MUSCLE-TISSUE ARE INDEPENDENT OF AGE OR GENDER IN NORMAL HUMAN ADULTS - A WESTERN-BLOT STUDY

Sera from 69 healthy blood donors were screened for autoantibodies usi ng Western blots of human muscle fractions to assess whether prevalenc e and repertoires of autoantibodies against muscle tissue would change with age. Each serum contained immunoglobulins binding to a broad spe ctrum of antigens. Their molecular masses ranged from 20 to more than 200 kDa. Although each staining pattern appeared to be a singular comb ination of detected bands and staining intensities, the patterns were not different in men and women. When sera were grouped according to ag e (decades between 10 and over 70 years) age-dependent changes were no t found. Individual repertoires of natural autoantibodies against musc le tissue are complex when examined by Western blotting. Mature normal repertoires of low-affinity autoantibodies are found at the age of 10 years which is the lower cut-off in this study. The repertoires remai n stable throughout a normal lifespan.