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US5549834A Expired / Lapsed US ⏱️ 0.0 years remaining

Systems and methods for reducing the number of leukocytes in cellular products like platelets harvested for therapeutic purposes

Assignee: Fenwal Inc
•
Filing: 1995-05-30
•
Granted: 1996-08-27
•
Expires: 2015-05-30
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Abstract

Abstract Systems and methods are provided for reducing the number of leukocytes in cellular products like platelets collected in an on line or continuous blood separation processes. The systems and methods reduce the number of leukocytes from a cellular suspension before its separation into a cellular-rich concentration. This leads to effective and efficient leukocyte removal and a high quality blood product suited for therapeutic use, with and without long term storage.

Inventors

  • 👤 Richard I. Brown

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-05 05:51
CPC Classifications
B; B04; B04B; B04B13/00; A; A61; A61M; A61M1/00; A61M1/02; A61M1/0209; A61M1/0218; A61M1/14; A61M1/30; A61M1/301; A61M1/302; A61M1/303; A61M1/305; A61M1/308; A61M1/36; A61M1/3601; A61M1/3603; A61M1/3621; A61M1/3624; A61M1/3693; A61M1/3696; B01; B01D; B01D17/00; B01D17/02; B01D17/0217; B01D21/00; B01D21/24; B01D21/2405; B01D21/245; B01D21/26; B01D21/262; B01D21/30; B01D21/34; B04B5/00; B04B5/04; B04B5/0442; B04B7/00; B04B7/08; A61M2202/00; A61M2202/04; A61M2202/0413; A61M2202/0427; A61M2205/00; A61M2205/33; A61M2205/3331; A61M2205/3344; A61M2205/3351; A61M2205/3355; B01D2221/00; B01D2221/08; B01D2221/10; B04B2005/045

Claims Analysis

Total Claims: 11
Claim 1
Independent Claim 299 words
A system for obtaining a platelet-rich concentrate having a reduced number of leukocytes comprising a first separation chamber to separate a suspension of platelets from whole blood, the first separation chamber having an entry region to receive whole blood, the whole blood having a surface hematocrit in the entry region, a second separation chamber to separate the suspension of platelets into a platelet-rich concentrate and platelet-poor component, a filter for removing leukocytes from the suspension of platelets, the filter having an inlet and an outlet, a first path communicating with the first separation chamber and a source of whole blood including a first pump to convey whole blood through the first path into the entry region of the first separation chamber, a second path communicating with the first separation chamber and the filter inlet including a second pump to convey platelet suspension from the first separation chamber into the filter, a third path communicating with the second separation chamber and the filter outlet to convey filtered platelet suspension from the filter into the second separation chamber, a fourth path communicating with the first and second paths and bypassing the filter, the fourth oath including a third pump to convey platelet suspension in the second path to the first path for mixing with whole blood conveyed into the first separation chamber, and a controller coupled to the first pump, the second pump, and the third pump, the controller operating the first pump at a first selected pumping rate, the second pump at a second selected pumping rate less than the first selected pumping rate, and the third pump at a selected variable percentage of the first pumping rate to maintain the surface hematocrit of whole blood in the entry region of the first separation chamber within a predetermined desired range.
Claim 2
Independent Claim 299 words
A system for obtaining a platelet-rich concentrate having a reduced number of leukocytes comprising a first separation chamber to separate a suspension of platelets from whole blood, the first separation chamber having an entry region to receive whole blood, the whole blood having a surface hematocrit in the entry region, a second separation chamber to separate the suspension of platelets into a platelet-rich concentrate and platelet-poor component, a filter for removing leukocytes from the suspension of platelets, the filter having an inlet and an outlet, a first path communicating with the first separation chamber and a source of whole blood including a first pump to convey whole blood through the first path into the entry region of the first separation chamber, a second path communicating with the first separation chamber and the filter inlet including a second pump to convey platelet suspension from the first separation chamber into the filter, a third path communicating with the second separation chamber and the filter outlet to convey filtered platelet suspension from the filter into the second separation chamber, a fourth path communicating with the first and second paths and bypassing the filter, the fourth oath including a third pump to convey platelet suspension in the second path to the first path for mixing with whole blood conveyed into the first separation chamber, and a controller coupled to the first pump, the second pump, and the third pump, the controller operating the first pump at a first selected pumping rate, the second pump at a second selected pumping rate less than the first selected pumping rate, and the third pump at a selected variable percentage of the first pumping rate to maintain the surface hematocrit of whole blood in the entry region of the first separation chamber within a predetermined desired range.
Claim 3
Dependent Claim 33 words
A system according to claim 1 wherein operation of the system comprises a separation process and wherein the first path remains in communication with the whole blood source substantially throughout the separation process.
Claim 4
Dependent Claim 31 words
A system according to claim 1 wherein the first and second separation chambers rotate in a rotational field about an axis, and wherein the filter is located outside the rotational field.
Claim 5
Dependent Claim 22 words
A system according to claim 1 wherein the control means operates the first, second, and third pumps in a substantially continuous manner.
Claim 6
Independent Claim 174 words
A method for obtaining a platelet-rich concentrate having a reduced number of leukocytes comprising introducing whole blood from a source at a selected first pumping rate into a first separation chamber, the whole blood having a surface hematocrit when introduced into the first separation chamber, separating the whole blood in the first separation chamber into a suspension of platelets, conveying the suspension of platelets through a filter at a selected second pumping rate less than the first pumping rate from the first separation chamber into a second separation chamber to reduce the number of leukocytes, separating the filtered suspension of platelets in the second separation chamber into a platelet-rich concentrate and platelet-poor component, diverting a portion of the suspension of platelets from the first separation chamber at a third selected pumping rate prior to filtration, mixing the diverted portion with whole blood introduced into the first separation chamber, and controlling the third selected pumping rate to maintain the surface hematocrit of whole blood introduced into the first separation chamber within a predetermined desired range.
Claim 7
Independent Claim 174 words
A method for obtaining a platelet-rich concentrate having a reduced number of leukocytes comprising introducing whole blood from a source at a selected first pumping rate into a first separation chamber, the whole blood having a surface hematocrit when introduced into the first separation chamber, separating the whole blood in the first separation chamber into a suspension of platelets, conveying the suspension of platelets through a filter at a selected second pumping rate less than the first pumping rate from the first separation chamber into a second separation chamber to reduce the number of leukocytes, separating the filtered suspension of platelets in the second separation chamber into a platelet-rich concentrate and platelet-poor component, diverting a portion of the suspension of platelets from the first separation chamber at a third selected pumping rate prior to filtration, mixing the diverted portion with whole blood introduced into the first separation chamber, and controlling the third selected pumping rate to maintain the surface hematocrit of whole blood introduced into the first separation chamber within a predetermined desired range.
Claim 8
Dependent Claim 30 words
A method according to claim 5 wherein in the step of controlling the third selected pumping rate, the surface hematocrit is maintained within the range of about 30% to 35%.
Claim 9
Dependent Claim 100 words
A method according to claim 5 and further including the step of adding at least one fluid to the whole blood before separation within the first separation chamber, and wherein in the step of controlling the third selected pumping rate, the third selected pumping rate is maintained as a percentage of the first selected pumping rate (% RE ), governed as follows: %.sub.RE =K*Hct-100 where: Hct is the hematocrit of the whole blood in the source, and K is a dilution factor that takes into account the volume of the at least one fluid are added to the whole blood.
Claim 10
Dependent Claim 38 words
A method according to claim 5 and further including the step of maintaining communication between the whole blood source and the first separation chamber substantially throughout the period that separation occurs in the first and second separation chambers.
Claim 11
Dependent Claim 58 words
A method according to claim 5 wherein, in the steps of separating whole blood in the first separation chamber and separating platelet suspension in the second separation chamber, the first and second separation chambers rotate about an axis in a centrifugal field, and wherein, while filtering the platelet suspension, the platelet suspension is located outside the centrifugal field.

References Cited (Backward Citations)

US2848995A Cited
US3064647A Cited
US3244363A Cited
US3672564A Cited
US3347454A Cited
US3489145A Cited
US3655123A Cited
US3561672A Cited
US3519201A Cited
USRE29738E Cited
US3701434A Cited
US3858796A Cited
US3857393A Cited
US3953329A Cited
US3786919A Cited
US3737096A Cited
US3748101A Cited
US3802432A Cited
US3964467A Cited
US3825175A Cited
US3987961A Cited
US3986506A Cited
US4013564A Cited
US4056224A Cited
US4113173A Cited
US3957197A Cited
US4007871A Cited
US4010894A Cited
US4425112A Cited
US4636193A Cited
US4734089A Cited
US4091989A Cited
US4098456A Cited
US4235233A Cited
US4430072A Cited
US4120448A Cited
US4194684A Cited
US4120449A Cited
US4109854A Cited
US4094461A Cited
US4111356A Cited
US4419089A Cited
US4230263A Cited
US5217426A Cited
US5217427A Cited
US4934995A Cited
US5006103A Cited
US4114802A Cited
US4108353A Cited
US4191182A Cited
US4387848A Cited
US4164318A Cited
US4146172A Cited
US4185629A Cited
US4379452A Cited
US4109852A Cited
US4109855A Cited
USD255935S Cited
USD255936S Cited
US4127231A Cited
US4142670A Cited
US4246107A Cited
US4330410A Cited
US4278201A Cited
US4386730A Cited
US4278202A Cited
USD258909S Cited
US4244513A Cited
US4187979A Cited
US4261507A Cited
US4223672A Cited
US4216770A Cited
US4215688A Cited
US4278592A Cited
US4266717A Cited
US4283004A Cited
US4416777A Cited
US4344560A Cited
US4330080A Cited
US4322275A Cited
US4321192A Cited
US4357235A Cited
US4283276A Cited
US4269718A Cited
US4350156A Cited
US4350283A Cited
US4343705A Cited
US4316576A Cited
US4405079A Cited
US4432871A Cited
US4353795A Cited
US4512763A Cited
US4421503A Cited
US4402680A Cited
US4729829A Cited
US4411792A Cited
US4464167A Cited
US4923439A Cited
US4531932A Cited
US4446014A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1999-08-27 2000-02-26 2000-08-27 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2003-08-27 2004-02-26 2004-08-27 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2007-08-27 2008-02-26 2008-08-27 $7700.00 Window Closed / Lapsed

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