Elimination of undesirable immunoglobulin contaminants including aggregated IgG from gamma-globulin preparations by jackfruit lectin affinity chromatography.

Jackfruit lectin, jacalin, has been characterized to combine with IgA of only IgA1 subclass but not with IgA2 subclass and other immunoglobulins. However, we found in the present study that a lectin from another batch of jackfruit (Jacalin-H) showed a different nature in binding reaction. Jacalin-H combined with immunoglobulins of every class or subclass except monomer IgG. More interestingly, the Jacalin-H also combined with aggregated IgG. By means of the Jacalin-H affinity chromatography, we could efficiently eliminate aggregated IgG as well as immunoglobulins other than monomer IgG from commercial gamma-globulin preparations. Jacalin-H affinity chromatography is easy, inexpensive and efficient in the elimination of undesirable immunoglobulin contaminants in the commercial gamma-globulin preparations.