Systems and methods for separating blood under conditions of reduced plasma clarity

Patent metadata

Field	Value
Publication number	US-11285250-B2
Application number	US-201815912893-A
Country	US
Kind code	B2
Filing date	Mar 6, 2018
Priority date	Mar 7, 2017
Publication date	Mar 29, 2022
Grant date	Mar 29, 2022

Abstract

Blood separation systems and methods are provided for separating blood under conditions of reduced plasma clarity. The system may assess plasma clarity by monitoring light transmissivity of plasma or comparing an actual plasma flow rate to an ideal plasma flow rate, with a low flow rate indicating decreased clarity, which may be addressed by increasing the plasma flow rate. For extracorporeal photopheresis, plasma clarity may be a factor in determining the dosage of irradiating light to apply to mononuclear cells. A fluid processing assembly for mononuclear cell collection may include visual indicium, which an operator may use to determine when to end mononuclear cell collection. The system may detect red blood cells flowing toward a mononuclear cell collection container and reverse the direction of flow to prevent red blood cells from entering the container. An operator may also be enabled to selectively begin and/or end harvesting of mononuclear cells.

First claim

The invention claimed is:

1. A fluid processing system, comprising:
a blood separation chamber configured to separate mononuclear cells from a plasma constituent of blood;
an outlet flow path associated with the blood separation chamber for alternately removing at least a portion of said plasma constituent and at least a portion of said mononuclear cells from the blood separation chamber, wherein the outlet flow path includes a valve station movable between first and second conditions to change the direction of flow of fluid through the outlet flow path;
a mononuclear cell collection container in fluid communication with the outlet flow path; and
a controller programmed to execute a mononuclear cell collection procedure including a build-up phase in which a volume of the mononuclear cells increases in the blood separation chamber and a harvest phase in which the mononuclear cells are flowed from the blood separation chamber to the mononuclear cell collection container, wherein
the harvest phase comprises a first stage in which said at least a portion of said plasma constituent flows through the outlet flow path and the controller causes the valve station to be in the first condition to direct a flow of said at least a portion of said plasma constituent away from the mononuclear cell collection container and a second stage in which said at least a portion of said mononuclear cells flows through the outlet flow path and the controller causes the valve station to be in the second condition to direct a flow of said at least a portion of said mononuclear cells through the outlet flow path to the mononuclear cell collection container,
the controller is programmed to allow an operator to selectively and substantially instantaneously transition from the first stage of the harvest phase to the second stage of the harvest phase, and
the controller is further programmed to allow an operator to selectively and substantially instantaneously end the second stage of the harvest phase.

2. The fluid processing system of claim 1 , wherein the mononuclear cell collection procedure executed by the controller includes a plurality of cycles of alternating said build-up and harvest phases.

3. The fluid processing system of claim 2 , wherein the controller is programmed with default times for transitioning from the first stage of the harvest phase to the second stage of the harvest phase and/or for ending the second stage of the harvest phase, and the controller is further programmed
to transition from the first stage of the harvest phase to the second stage of the harvest phase at a time that is different from the default time for transitioning from the first stage of the harvest phase to the second stage of the harvest phase in a cycle based on the time at which the operator selectively transitioned from the first stage of the harvest phase to the second stage of the harvest phase during a previous cycle, and/or
to end the second stage of the harvest phase at a time that is different from the default time for ending the second stage of the harvest phase in a cycle based on the time at which the operator selectively ended the second stage of the harvest phase during a previous cycle.

4. The fluid processing system of claim 2 , wherein the controller is programmed with default times for transitioning from the first stage of the harvest phase to the second stage of the harvest phase and/or for ending the second stage of the harvest phase, and the controller is further programmed
to transition from the first stage of the harvest phase to the second stage of the harvest phase at the default time for transitioning from the first stage of the harvest phase to the second stage of the harvest phase in a cycle regardless of whether the operator selectively transitioned from the first stage of the harvest phase to the second stage of the harvest phase during a previous cycle, and/or
to end the second stage of the harvest phase at the default time for ending the second stage of the harvest phase in a cycle regardless of whether the operator selectively ended the second stage of the harvest phase during a previous cycle.

5. The fluid processing system of claim 1 , wherein the controller is programmed with default times for transitioning from the first stage of the harvest phase to the second stage of the harvest phase and/or for ending the second stage of the harvest phase, and the controller is further programmed to limit the ability of the operator to selectively transition from the first stage of the harvest phase to the second stage of the harvest phase and/or to end the second stage of the harvest phase to predetermined ranges to prevent transitioning from the first stage of the harvest phase to the second stage of the harvest phase and/or ending the second stage of the harvest phase at times that are too early or too late compared to the default times.

6. The fluid processing system of claim 1 , wherein the outlet flow path is defined at least in part by a flexible tubing and a rigid cassette.

7. The fluid processing system of claim 6 , wherein the valve station is incorporated into the cassette.

8. A method for collecting mononuclear cells, comprising:
separating mononuclear cells from a plasma constituent of blood in a blood separation chamber;
executing a build-up phase in which a volume of the mononuclear cells increases in the blood separation chamber; and
executing a harvest phase comprising a first stage in which at least a portion of said plasma constituent flows via an outlet flow path with a valve station of the outlet flow path in a first condition to direct a flow of said at least a portion of said plasma constituent through the outlet flow path away from a mononuclear cell collection container in fluid communication with the outlet flow path and a second stage in which at least a portion of said mononuclear cells flows out of the blood separation via the outlet flow path with the valve station in a second condition to direct a flow of said at least a portion of said mononuclear cells through the outlet flow path to the mononuclear cell collection container, wherein an operator is enabled to selectively and substantially instantaneously transition from the first stage of the harvest phase to the second stage of the harvest phase and to selectively and substantially instantaneously end the second stage of the harvest phase.

9. The method of claim 8 , further comprising a plurality of cycles of alternating said build-up and harvest phases.

10. The method of claim 9 , further comprising default times for automatically transitioning from the first stage of the harvest phase to the second stage of the harvest phase and/or for ending the second stage of the harvest phase, wherein
the first stage of the harvest phase automatically transitions to the second stage of the harvest phase at a time that is different from the default time for transitioning from the first stage of the harvest phase to the second stage of the harvest phase in a cycle based on the time at which the operator selectively transitioned from the first stage of the harvest phase to the first stage of the harvest phase during a previous cycle, and/or
the second stage of the harvest phase automatically ends at a time that is different from the default time for ending the second stage of the harvest phase in a cycle based on the time at which the operator selectively ended the second stage of the harvest phase during a previous cycle.

11. The method of claim 9 , further comprising default times for automatically transitioning from the first stage of the harvest phase to the second stage of the harvest phase and/or for ending the second stage of the ha

Assignees

• Fenwal Inc

Inventors

• Nguyen Lan T
• Prendergast Jonathan W
• Ali Zahra R
• Abedin Tanima J
• Erickson Molly
• Hershenhouse Korri

Classifications

• A61M2205/3303

  Using a biosensor · CPC title

• A61M2205/12

  with interchangeable cassettes forming partially or totally the fluid circuit · CPC title

• B01L2200/0652

  Sorting or classification of particles or molecules · CPC title

• A61M2202/0439

  White blood cells; Leucocytes · CPC title

• G01N33/491

  by separating the blood components (G01N15/05 takes precedence) · CPC title