Thank you for your interest in my poster. You are obviously more observant than I am, as you noticed the concentration of NaCl was incorrect. The NaCl concentration in PBS is 0.15 M, which makes the solution isotonic.
In response to your second question: The sodium azide is added to inhibit ATP generation. This is a common procedure in flow cytometry. It is intended to prevent the endocytosis of the fluorescent antibody by the cell.
In response to your third question: The potassium oxalate was 2 mg/ml. the tubes also contained 2.5 mg/ml sodium fluoride. It is very likely that cell activation did occur, resulting in the shedding of CD62 (L-selectin). It is also possible that the anticoagulants directly inhibited binding of the anti-CD62 antibody. The anticoagulants were chosen to represent those used in the Saint Elizabeth Hospital Emergency Room. We are interested in using pre-collected blood for clinical studies and were testing the effect of the various anticoagulants on cell adhesion molecule detection.