Binding of gamma-globulin fragments to muscle tissue

Abstract

Serum γ-globulins from normal persons and from twenty-four patients with myasthenia gravis were tested in the antiglobulin consumption test before and after pepsin digestion.

F(ab')₂ fragments prepared from normal sera did not bind to muscle tissue, while Fc fragments did. Accordingly, muscle binding γ-globulins from normal sera bind to the tissue only by the Fc portion of the molecule.

F(ab')₂ preparations from sera from patients with myasthenia gravis combined with the tissue. In twelve of these sera, the amount of muscle binding γ-globulin was shown to be quantitatively within normal limits. The difference in binding capacity registered between the different patient sera is quantitative, while the data indicate a qualitative difference between normal and patient sera.