Table 2.

Dose-dependent binding of IgA and expression of IgA receptors on cell surface of various types of cellsa

Cell Type Binding of sIgA and IgA
Secretory IgA (mg/ml) Serum IgA (mg/ml)
0 1.25 2.5 5 10 0 1.25 2.5 5 10
U937 3.25 11.20 19.58 29.41 32.15 2.97 8.56 15.56 26.58 28.65
HMC 3.16 7.45 21.72 30.56 35.54 2.89 6.58 22.54 35.68 41.46
HepG2 2.69 5.68 12.56 17.89 21.47 2.87 4.56 11.07 15.26 18.59
HT29 3.12 4.56 5.23 6.78 6.90 2.91 4.05 5.07 5.98 6.23
Expression of IgA Receptor
CD89 ASGPR pIgR
H1 H2
U937 + + + neg neg neg
HMC neg neg neg neg
HepG2 neg + + + + neg
HT29 neg neg neg +
neg, MFI is no different from that of the isotypic control; +, MFI is 1.2- to twofold greater than that of the isotypic control; + +, MFI is 2- to 2.5-fold greater than that of the isotypic control; + + +, MFI is at least 2.5-fold greater than that of the isotypic control.
  • a For IgA binding, results are expressed as the average MFI of two individual experiments. MFI, mean fluorescence intensity; sIgA, secretory IgA; HMC, human mesangial cells. Other abbreviations as in Table1.