When incompatible blood is given, antibodies and complement in the recipient plasma attack the antigens on the donor RBC. Hemolysis ensues The antigen-antibody complex activate the Hageman factor (factor XII), which acts on the kinin system to produce bradykinin
Still it is not advisable to take it after the expiry date written on the bottle. This is just for your information to let you know that you are safe. Anyway Saline Nasal spray is not going to do any harm even if you used an expired one. So forget about it.
The new Air Miles expiry policy can now expire; in fact starting December 31st, 2011, all Air Miles reward miles in your account will have a date stamp of 5 years. What this means is that any reward miles you have earned before December 31st, 2011 will have to be redeemed by December 31st, 2016.