Patent attributes
Methods wherein a blood cell concentration gradient is formed in a pooling unit in which blood is pooled before or after introducing the blood into a filter for eliminating leukocytes followed by the filtration are disclosed. By the first method comprising forming a blood cell concentration gradient in the pooling unit before introducing blood into the filter for eliminating leukocytes followed by the filtration, leukocytes can be efficiently eliminated from a whole blood preparation or a high platelet collection ratio can be established while maintaining a high leukocyte elimination ratio. By the second method comprising forming a blood cell concentration gradient in the pooling unit after introducing blood into the filter for eliminating leukocytes followed by the filtration, leukocytes can be efficiently eliminated from a whole blood preparation or a platelet preparation and platelets can be collected at a high ratio.
