Effects of interleukin 4 on production of IgE monoclonal antibodies directed against glucose oxidase.
Interleukin 4 is a cytokine that promotes the growth of B cells and the synthesis of IgE subclass antibody. Here we report the results of our study that was designed to determine if recombinant murine interleukin 4 (rmIL-4) can increase the yield of hybridomas secreting IgE subclass monoclonal antibodies directed against glucose oxidase. Three BALB/c mice (test group) were primed i.p. with 50 micrograms of glucose oxidase and then boosted i.v. 2 weeks later with 5 micrograms of glucose oxidase plus 200 ng of rmIL-4. A standard hybridoma fusion was performed 3 days later, and the fusion products were then cultured in the presence of 20 ng of rmIL-4 per milliliter. Another group of three mice underwent an identical immunization and fusion procedure, except that the rmIL-4 was omitted (control group). At 21 days after fusion, the test group had a significantly greater frequency of wells with hybridomas (average frequency = 191 per 1000 wells in test group versus 58 in control group; chi 2 = 1803; p = 0.0001) and wells containing IgG anti-glucose oxidase (mean of 23 per 1000 wells in test group versus 3 in control group; chi 2 = 506, p = 0.0001). Moreover, the IL-4-treated group had a significantly higher frequency of wells containing IgE antibodies (mean of 44 versus 11 in control group; chi 2 = 288, p = 0.0001) and IgE antibodies directed against glucose oxidase (mean of 5 per 1000 wells versus 2 in control group; chi 2 = 21, p = 0.0001).(ABSTRACT TRUNCATED AT 250 WORDS)