The present invention provides devices and methods for concentrating a fluid and for treating a patient with the concentrated fluid. The concentrator apparatus includes a main housing (12) defining a separation chamber (14), a filter housing (48) containing a filter (46) comprising a filter element, a piping (44) for moving concentrated fluid from the separation chamber to the filter, and ports (32) for pressurizing the concentrated fluid past the filter element of the filter. The present invention also provides a variety of uses of concentrated body fluids, including autologous concentrated body fluid. The concentrated fluids can be used for example in surgical applications, including graft applications such as allograft, xenograft and autograft applications.