Bone marrow donations Published Oct. 19, 2012 28th Bomb Wing Public Affairs ELLSWORTH AIR FORCE BASE, S.D. -- Airmen and their families interested in registering in the national bone marrow database can stop by the 28th Medical Group Laboratory during normal business hours. Individuals must complete a registration form and have four oral swabs collected to be added to the database. For more information or to register, call the 28th MDG Laboratory at (605) 385-3459.