Western blot analyses of neutrophil lysates with anti–siglec-5 antiserum. Samples, either reduced (R) or nonreduced (NR), were separated on a 10% polyacrylamide gel and transferred to nitrocellulose. The blot was incubated with anti–siglec-5 antiserum at 1:2,000 dilution or preimmune serum at 1:1,000 dilution, washed, and incubated with ¹²⁵I-antirabbit IgG. No signal was observed with preimmune serum (not shown) but a predominant band at approximately 70 kD and approximately 140 kD can be seen under reducing and nonreducing conditions, respectively.