Katsuhiko Tomibe

Development of an Intravenous γ‐Globulin with Fc Activities

Abstract. S‐sulfonated γ‐globulin (S‐GG) was prepared by treating γ‐globulin with sulfite and tetrathionate ions. About four interchain disulfide bonds were selectively cleaved to give S‐sulfonate groups. Although the above treatment strongly suppresses anticomplementary activity and nonspecific skin reactivity, the resulting S‐GG retains high antibody activity. Furthermore, S‐GG was found to maintain satisfactory levels for prolonged periods in vivo. The physicochemical and antigenic analyses of S‐GG suggest that the S‐sulfonation induces structural modification only at restricted sites.

Generation of hybridomas producing human monoclonal antibodies against herpes simplex virus after invitro stimulation

Hybridomas producing human monoclonal antibodies against herpes simplex virus were generated by in vitro antigen stimulation before cell fusion. The cell fusion with tonsillar lymphocytes which were stimulated with antigen and/or pokeweed mitogen generated many hybridomas producing human IgG against the virus. A combination of antigen and pokeweed mitogen synergistically enhanced the generation of virus-specific hybridomas. Furthermore, the higher the antibody response of the tonsil, the more virus-specific hybridomas were generated by the cell fusion. These results suggest that cell fusion with in vitro stimulated lymphocytes can be applied to a variety of clinically relevant viruses.

Clinical Effect and Metabolism of S‐Sulfonated Immunoglobulin in 7 Patients with Congenital Humoral Immunodeficiency

Abstract. 7 patients with primary humoral immunodeficiency were given an S‐sulfonated IgG preparation, 100 mg/kg i.v. at intervals of 3–4 weeks, for treatment of, or prophylaxis against, infection. The clinical effects and metabolism of S‐sulfonated IgG were studied. No side reactions attributable to S‐sulfonated IgG occurred in any of the patients. The S‐sulfonated IgG was completely transformed into intact IgG within 24 h after administration, and had a mean half‐life of 21 days, comparable to that of intact IgG. Complete restoration of IgG Fc fragment activity occurred within 24 h following injection, as assessed by reversed passive cutaneous anaphylaxis.