Opsonic activity of agammaglobulinemia serum determined by oxygen consumption capacity of leukocytes.

In evaluating the therapeutic efficacy of gammaglobulin preparations in patients with agammaglobulinemia, opsonic activity of patients' sera in terms of oxygen consumption capacity of normal leukocytes is advocated as a useful index. Although the serum lgG level is a commonly used indicator, its determination alone was found out not always to reflect antibody levels in such sera. The method described here is simple and gives quantitative results and deserves a wider trial in controlling gammaglobulin replacement therapy.