Where possible, PeproTech obtains International Unit (IU) values through multiple side-by-side comparisons of our product(s) against the analogous WHO Reference Standard within our biological activity assay. Performing multiple comparison tests allows us to account for any outliers due to possible variations with the assay (e.g. product, handling, assay protocol, etc.). Using the results of these comparisons we can provide a reliable quantification of our product’s activity in relation to the activity of the WHO Reference Standard.


The IU values obtained by PeproTech are applicable across Lot Numbers of a specific Catalog Number as our testing covers multiple Lot Numbers of comparable activity. These values are based on comparison testing and are subject to change.

Cytokine Name
PeproTech
Catalog Number(s)
PeproTech
Bioassay Cell Line
 
WHO
Catalog Number
PeproTech
Units (IU/ng)
PeproTech
Units (IU/μg)
Human IL-1α
mouse D10S
 
86/632
64.9
64900
Human IL-1β
mouse D10S
 
86/680
70.3
70300
Human IL-2
mouse CTLL-2
 
86/500
2.18
2180
Human IL-3
human TF-1
 
91/510
2.8
2800
Human IL-4
human TF-1
 
88/656
16.1
16100
Human IL-6
mouse 7TD1
 
89/548
123
123000
Human IL-7
mouse 2E8
 
90/530
117
117000
Human IL-10
mouse MC/9
 
93/722
22.6
22600
Human IL-13
human TF-1
 
94/622
0.79
790
Human IL-15
mouse CTLL-2
 
95/554
28.7
28700
H/M/R Activin A
mouse MPC-11
 
91/626
0.001
1
H/M/R BDNF
rat C6
 
96/534
1.9
1900
H/M/R BMP-2
mouse ATDC-5
 
93/574
0.9
900
Human EGF
mouse Balb/c 3T3
 
91/530
1
1000
Human EPO
human TF-1
 
11/170
0.16
160
Human FGF-basic
mouse Balb/c 3T3
 
90/712
0.65
650
Human Flt3-Ligand
human AML5
 
96/532
1.1
1100
Human G-CSF
mouse NFS-60
 
09/136
101.3
101300
Human GDNF
human SH-SY5Y
 
09/266
0.78
780
Human GM-CSF
human TF-1
 
88/646
12.8
12800
Human HGF
monkey 4MBr-5
 
96/564
0.21
210
Human IFN-α
human TF-1
 
95/650
263
263000
Human IFN-β
human TF-1
 
00/572
504
504000
Human IFN-γ
human HT-29
 
87/586
1.94
1940
Human IGF-I
mouse FDC-P1
 
91/554
0.001
1
Human IGF-II
mouse FDC-P1
 
96/538
0.6
600
Human KGF
monkey 4MBr-5
 
03/150
2.33
2330
Human LIF
human TF-1
 
93/562
12.2
12200
Human M-CSF
mouse M-NSF-60
 
89/512
100
100000
Human β-NGF
human TF-1
 
93/556
0.53
530
Human PDGF-BB
mouse Balb/c 3T3
 
94/728
2.65
2650
Human SCF
human TF-1
 
91/682
1.7
1700
Human TGF-β1
mouse HT-2
 
89/514
9
9000
Human TGF-β3
mouse HT-2
 
09/234
5.64
5640
Human TNF-α
mouse L929
 
12/154
39.1
39100
Human sTRAIL/Apo2L
human LN-18
 
04/166
1.45
1450
Human VEGF165
HUVEC
 
02/286
0.69
690
Murine IL-2
mouse CTLL-2
 
93/566
129
129000
Murine IL-3
mouse NFS-60
 
91/662
132
132000
Murine IL-4
mouse HT-2
 
91/656
19.8
19800
Murine IL-6
mouse 7TD1
 
93/730
322
322000
Murine GM-CSF
mouse FDC-P1
 
91/658
44.3
44300