Figure 5.

Comparison of expression of FcγRIII (A) and FcɛRII (CD23) (B) receptor mRNAs by using RT-PCR in rabbit ASM cells after 0, 6-, and 24-hr treatment with 10% control serum and 10% atopic asthmatic sensitizing serum. Expression of α-actin was used to control for loading. cDNA from activated U937 cells (i.e., for FcγRIII) and the immortalized human B-cell line 8.1.6 (i.e., for FcɛRII) were used as positive controls. Note in contrast to FcγRIII, expression of FcɛRII is significantly up-regulated at 24 hr (i.e., >2-fold) after treatment with atopic asthmatic serum.