The red cell chemokine receptor is distinct from the Fy6 epitope.

BACKGROUND

Previous studies established an association between the red cell chemokine receptor and Fy6 of the Duffy glycoprotein. The relationship between Duffy system antigens and interleukin 8 binding by red cells was examined.

STUDY DESIGN AND METHODS

Interleukin 8 adsorption was measured by using red cells from owl, squirrel, and rhesus monkeys, and human red cells before and after saturation with anti-Fya (anti-Fy1), anti-Fyb (anti-Fy2), or anti-Fy6. The effect of cell saturation with interleukin 8 on Duffy system antigen expression and the effect of enzyme treatment on interleukin 8 adsorption were also examined.

RESULTS

Fy:1,-2,6 or Fy:-1,2,6 (owl monkey, squirrel monkey, human) red cells adsorbed interleukin 8 over a wide range of concentrations (125-1000 pg/mL). Human Fy:-1,-2,-6 red cells bound minimal interleukin 8. Human red cells saturated with corresponding antibodies displayed decreased interleukin 8 binding. Saturation of human cells with interleukin 8 failed to interfere with Duffy system antigen expression. Rhesus monkey cells lacking Fy1, Fy2, and Fy6 were able to adsorb interleukin 8 in a manner similar to Fy:1,-2,6 or Fy:-1,2,6 primate cells. Ficin treatment eliminated both Duffy system antigen expression and interleukin 8 adsorption from red cells.

CONCLUSIONS

The Duffy glycoprotein binds interleukin 8. Although previous studies suggested that interleukin 8 bound either directly to or close to the Fy6 epitope, the ability of Fy:-1,-2,-6 rhesus monkey cells to adsorb interleukin 8 suggests that the interleukin 8 receptor is distinct from Fy6, Fy1, and Fy2.