Purification of bispecific F(ab')2 from murine trinoma OC/TR with specificity for CD3 and ovarian cancer.

A study was made of the stability of the murine bispecific trinoma OC/TR with respect to secretion of both types of parental heavy and light chains. OC/TR is a cell line producing bispecific antibody that reacts with the CD3 antigen on T cells and the folate-binding receptor--frequently found to be overexpressed on ovarian carcinoma cells. Of the 10 different IgG combinations theoretically possible with 2 heavy and 2 light chains, 6 combinations were secreted. Subclones varied considerably in relative production of the two parental heavy and light chains. A detailed analysis was made of the binding characteristics and retargeting activity of each of the IgGs produced. From a clone producing a relatively high quantity of bispecific IgG, a large-scale production was initiated. The purification of clinical grade bispecific F(ab')2 from harvest fluids is described. The yield from this purification process was found to be comparable to the yield of bispecific F(ab')2 after chemical cross-linking of two different Fab'.

Impaired energy metabolism in platelets from patients with Wiskott-Aldrich syndrome.

The platelet function defect seen in patients with Wiskott-Aldrich syndrome (WAS) has been ascribed to abnormal mitochondrial energy generation. The present study reveals a reduced energy content and low adenylate energy charge in platelets from two WAS-patients. Energy consumption in the resting platelets is slightly beyond the normal range, especially when ATP-resynthesis is primarily glycolytic. When platelets are stimulated with thrombin, the increase in energy consumption is 40-60% lower than in controls, both when energy is produced in glycolysis as when the mitochondria supply most of the energy. Analysis of the electron transport chain reveals no abnormalities. In contrast, the balance between glycolytic and mitochondrial ATP resynthesis is disturbed with a lowered contribution of oxidative ATP production. No such abnormalities are found in two WAS-carriers with the exception of a slight impairment in energy consumption during stimulation with thrombin. Thus, the platelet malfunction in WAS may be caused by a defect in the regulation of energy generation.

Potentiation of the cellular immune response by adjuvants: a limited role for adjuvant induced interferon.

Adjuvants differ in capacity to induce interferon (IFN). As a consequence IFN induction by adjuvants may influence their effectiveness in enhancement of delayed type hypersensitivity (DH) reactions. In this study, the lipophilic amine dimethyl dioctadecyl ammonium bromide (DDA), the synthetic double-stranded polynucleotide polyinosinic polycytidylic acid (poly I:C), liposomes and the polyols L 101 and L 121 were compared in BALB/c mice as inducers of IFN and also as adjuvants for DH to both lysozyme and inactivated Semliki Forest virus (SFV). The antigens were injected intracutaneously, alone or mixed with adjuvant. At day 6 after the immunization, DH was elicited and measured 24 h later as increase in footpad thickness. Negatively charged liposomes and polyol L 121 were unable to enhance DH to SFV and also lack the capacity to induce IFN. Polyol L 101 induced low levels of IFN and showed only slight adjuvanticity for DH to SFV. In contrast, DDA, a moderate IFN inducer, was shown to be a very effective adjuvant for induction of DH against both lysozyme and SFV. The excellent IFN inducer, poly I:C, at the tested dose range (0.03-3.0 mg/kg), displayed only a relatively weak adjuvant activity. But low doses of poly I:C (0.03 and 0.1 mg/kg) showed still adjuvanticity in contrast to equal doses of DDA. This might be related to sufficient induction of IFN by low doses of poly I:C but not by DDA. The discrepancy observed in the relation between IFN induction and a maximal DH induction suggests that IFN is not the only factor which enhances the effectiveness of adjuvants in induction of DH.(ABSTRACT TRUNCATED AT 250 WORDS)