BK110037 Summary

Section 1-4: 510(k) Summary

1.0:  Submitted By:

BD Biosciences
2350 Qume Drive
San Jose, CA 95131

Contact:
Nobuko Nakajima
Senior Regulatory Specialist
(408) 954-4109
(408) 954-2495 (FAX)
nobuko_nakajima@bd.com

Submission Date:
July 19, 2011

2.0: Device Name:

a) BD™ Stem Cell Enumeration Kit
21CFR 862.5220 Automated Differential Cell Counter (GKZ  Class II)

3.0: Intended Use:

The BD™ Stem Cell Enumeration (SCE) kit provides simultaneous enumeration of viable dual-positive CD45+/CD34+ hematopoietic stem cell populations in CD34+ absolute counts (cells/μL) as well as the percentage of the total viable leucocyte count that is CD34+ (%CD34). The following specimens can be analyzed with this kit: normal and mobilized peripheral blood, fresh and thawed leucopheresis products, fresh and thawed bone marrow, and fresh and thawed cord blood. The kit is intended for in vitro diagnostic (IVD) use on either a BD FACSCalibur™ flow cytometer using BD CellQuest™ or BD CellQuest™ Pro software or a BD FACSCanto™ II flow cytometer using BD FACSCanto™ software.

4.0: Basic description of the device:

The BD Stem Cell Enumeration kit is a direct immunofluorescence based three color Flow Cytometric in vitro Diagnostic assay with BD Trucount absolute counting beads either on a BD FACSCalibur™ flow cytometer using BD CellQuest™ or BD CellQuest™ Pro software, or a BD FACSCanto™ II flow cytometer using BD FACSCanto™ software.  It is designed for the simultaneous enumeration of dual-positive viable CD45+/CD34+ hematopoietic stem cell populations in absolute counts of CD34+ cells/µL, as well as the percentage of the total viable leucocyte count that is CD34+(%CD34) in normal and mobilized peripheral blood, fresh and thawed leucopheresis products, fresh and thawed cord blood and fresh or thawed bone marrow. 
The reagent kit consists of the following components:

• CD45-FITC/CD34-PE reagent provided in 1ml of phosphate-buffered saline (PBS) with BSA
• 10X ammonium chloride lysing solution
• 7-aminoactinomycin-D (7AAD) reagent
• BD Trucount tubes provided with a freeze-dried pellet of fluorescent beads
• Package Insert

5.0: Predicate Device:

The BD Stem Cell Enumeration kit is substantially equivalent to the Beckman Coulter Stem kit as cleared under BK040032, when used either on a BD FACSCalibur™ flow cytometer using BD CellQuest™ or BD CellQuest™ Pro software, or on a BD FACSCanto™ II flow cytometer using BD FACSCanto™ software.

6.0 Comparison to the Predicate Device:

Similarities and Differences:

Characteristic	BD Stem Cell Enumeration Kit (Test)	Beckman Coulter Stem Kit BK040032 (Predicate Device)
Intended Use	The BD™ Stem Cell Enumeration (SCE) kit provides simultaneous enumeration of viable dual-positive CD45+/CD34+ hematopoietic stem cell populations in CD34+ absolute counts (cells/µL) as well as the percentage of the total viable leucocyte count that is CD34+ (%CD34).	Same
	The following specimens can be analyzed with this kit: normal and mobilized peripheral blood, fresh and thawed leucopheresis products, fresh and thawed bone marrow, and fresh and thawed cord blood.	Same
	The kit is intended for use on either, a BD FACSCalibur™ flow cytometer with BD CellQuest™ or BD CellQuest Pro™ software, or a BD FACSCanto II flow cytometer using BD FACSCanto clinical software with BD Stem Cell Enumeration (SCE) Module.	Cell population measurements may be obtained using either an automated method or a manual method for gating and analysis. Refer to this Stem-Kit reagents package insert for complete instructions if using the manual method.
Device Classification and Product Code	Class II Product Code: GKZ CFR Section 864.5220	Same
Sample Type	Normal and mobilized peripheral blood, fresh and thawed leucopheresis products, fresh and thawed bone marrow, and fresh and thawed cord blood	Same
Reagent	BD Stem Cell Enumeration Kit CD45FITC/CD34PE reagent 7-aminoactinomycin-D (7AAD) reagent BD Trucount tubes Ammonium chloride Lysing solution	Beckman Coulter Stem Kit CD45FITC/CD34PE reagent CD45FITC/IsoClonic Control – PE reagent 7-AAD Viability Dye Ammonium chloride Lysing solution Stem-Count Fluorospheres
Principles – Method/Technology to identify population of interest	This assay is performed by staining the sample with the reagent in individual BD Trucount tubes for absolute counts. When a sample is added to the reagent, the fluorochrome-labeled antibodies in the reagent bind specifically to the cell surface. Additionally, the lyophilized pellet in the BD Trucount tubes dissolves, releasing a known number of fluorescent beads. Ammonium chloride is added to lyse erythrocytes before the sample is acquired on a flow cytometer. The dye 7-AAD is added to assess viability of the cells. Cells that are 7-AAD+ are not viable. During analysis of the sample, the concentration of viable CD34+ cells and viable CD45+ cells, and the percentage of viable CD34+cells in the viable CD45+ cell population, are calculated.	Same This test depends on the ability of a monoclonal antibody to bind to the surface of cells expressing discrete antigenic determinants. Specific cell surface staining is accomplished by incubating a biological specimen with the reagent. 7AAD viability dye, a nucleic acid dye that binds to accessible cellular DNA, is used to distinguish between viable and non viable cells. The red blood cells in each sample are lysed with ammonium chloride lysing solution. Samples are analyzed by flow cytometry with known number of manually-pipetted fluorescent beads to enumerate cell population of the interest.
Stain Stability	Within a maximum of 1 hour	Same
Number of tubes per assay	1 tube	3 tubes (2 samples and 1 IsoClonic control)
Measurement Range	CD34+ cells: 0 – 1,000 cells/µL	CD34+ cells: 0 – 2,000 cells/µL

7.0: Summary of Performance Data:

Equivalency for the candidate product has been demonstrated through method comparison, precision, linearity, stain stability, and reagent stability studies.

A) Summary of Method Comparison (Accuracy) study results:

Accuracy Study results of SCE Kit on BD FACSCanto II compared with the predicate method.
Variables	Bin	N	Absolute Difference		Relative Difference to Predicate
			Mean Absolute  Bias	95% CI	Mean Relative Bias	95% CI
Viable CD34	Low	167	-0.1	(-0.5 , 0.3)	NA	NA
	Mid	496	-0.7	(-1.4 , -0.04)	-1.6	(-3.1 , -0.2)
	High	255	-1.4	(-4.3 , 1.6)	-1.0	(-2.4 , 0.4)
% CD34 in CD45	Low	512	-0.004	(-0.01, 0.0002)	-2.2	(-4.4 , -0.1)
	High	406	0.08	(0.04 , 0.1)	2.1	(-0.1 , 4.3)

 

Regression analysis of SCE Kit for use on BD FACSCanto II platform:
Parameter	n	R2	Slope	Intercept
Viable CD34+ Absolute Count (cells/µL )	918	0.94	0.96 (0.95 , 0.98)	-0.15 (-0.25 , -0.05)
Percentage of total viable leucocyte count that are CD34+ (%)	918	0.92	1.05 (1.02 , 1.08)	-0.03 (-0.04 , -0.02)

 

Accuracy Study results of SCE Kit on BD FACSCalibur compared with the predicate method.
Variables	Bin	N	Absolute Difference		Relative Difference to Predicate
			Mean Absolute  Bias	95% CI	Mean Relative Bias	95% CI
Viable CD34	Low	156	-0.2	(-0.4 , 0.05)	NA	NA
	Mid	492	-0.5	(-1.3 , -0.02)	-0.9	(-2.3 , -0.5)
	High	257	-3.6	(-6.8 , -0.3)	-1.7	(-3.1 , 0.2)
% CD34 in CD45	Low	487	-0.002	(-0.01, 0.001)	-0.8	(-3.0 , 1.3)
	High	418	0.02	(0.09 , 0.2)	3.2	(0.9 , 5.5)

 

Regression analysis of SCE Kit for use on BD FACSCalibur platform:
Parameter	n	R2	Slope	Intercept
Viable CD34+ Absolute Count (cells/µL )	905	0.95	0.97 (0.96 , 0.98)	-0.11 (-0.19 , -0.03)
Percentage of total viable leucocyte count that are CD34+ (%)	905	0.92	1.06 (1.03 , 1.1)	-0.04 (-0.05 , -0.02)

B) Summary of System Precision study results:

Within-run precision of viable CD34+absolute counts (cells/µL)
	Mean	SD	%CV
BD SCE Control High on BD FACSCanto II	35.3	1.83	5.2
BD SCE Control High on BD FACSCalibur	35.5	1.69	4.8
BD SCE Control Custom Low on BD FACSCanto II	8.8	0.90	10.3
BD SCE Control Custom Low on BD FACSCalibur	8.8	0.75	8.6

 

Within-run precision of %CD34+
	Mean	SD	%CV
BD SCE Control High on BD FACSCanto II	0.58	0.03	4.7
BD SCE Control High on BD FACSCalibur	0.58	0.03	4.7
BD SCE Control Custom Low on BD FACSCanto II	0.15	0.01	9.6
BD SCE Control Custom Low on BD FACSCalibur	0.14	0.01	8.2

 

Total system precision of viable CD34+absolute counts (cells/µL)
	Mean	SD	%CV
BD SCE Control High on BD FACSCanto II	35.3	1.83	5.2
BD SCE Control High on BD FACSCalibur	35.5	2.02	5.7
BD SCE Control Custom Low on BD FACSCanto II	8.8	0.95	10.8
BD SCE Control Custom Low on BD FACSCalibur	8.8	0.82	9.3

 

Total system precision of %CD34+
	Mean	SD	%CV
BD SCE Control High on BD FACSCanto II	0.58	0.03	4.7
BD SCE Control High on BD FACSCalibur	0.58	0.03	5.1
BD SCE Control Custom Low on BD FACSCanto II	0.15	0.01	10.2
BD SCE Control Custom Low on BD FACSCalibur	0.14	0.01	9.4

C) Summary of System Linearity study results:
Linearity of the product performance was confirmed within the CD34+ absolute count reportable range of 0 – 1000 cells/µL.

D) Summary of Specimen Stability (Age of Blood/Age of Stain) study:
Age of blood and Age of Stain, when specimen was handled according to the instruction for use, were observed to be 24 hours and 1 hour, respectively.

E) Summary of Reagent Stability (Reagent Shelflife)
Kit component Reagent stability was assessed for each kit components, and the Kit was observed to be stable up to 20 month. Expiration dating may be extended in the future if ongoing product stability testing supports the extension.

This 510(k) Summary is being submitted in accordance with the requirements of compliance with SMDA 1990 and 21 CFR807.92