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WHO Unit Chart

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 200-01A
AF-200-01A
mouse D10S 86/632 64.9 64900
Human IL-1β 200-01B
AF-200-01B
mouse D10S 86/680 70.3 70300
Human IL-2 200-02
AF-200-02
mouse CTLL-2 86/500 2.18 2180
Human IL-3 200-03 human TF-1  91/510 2.8 2800
Human IL-4 200-04 human TF-1  88/656 16.1 16100
Human IL-6 AF-200-06 mouse 7TD1 89/548 123 123000
Human IL-7 200-07
AF-200-07
mouse 2E8  90/530 117  117000 
Human IL-10 200-10
AF-200-10
mouse MC/9  93/722  22.6  22600 
Human IL-13 200-13
AF-200-13
human TF-1 94/622  0.79  790 
Human IL-15 200-15
AF-200-15
mouse CTLL-2  95/554  28.7  28700 
H/M/R Activin A 120-14
120-14P
AF-120-14E
mouse MPC-11 91/626 .001  1
H/M/R BDNF 450-02
AF-450-02
rat C6 96/534  1.9  1900 
H/M/R BMP-2 120-02C mouse ATDC-5 93/574 0.9 900
Human EGF AF-100-15 mouse Balb/c 3T3 91/530  1.0  1000
Human EPO  100-64 human TF-1  11/170  0.16  160 
Human FGF-basic 100-18B
AF-100-18B
mouse Balb/c 3T3 90/712 0.65 650
Human Flt3-Ligand 300-19
AF-300-19
human AML5 96/532 1.1 1100
Human G-CSF 300-23
AF-300-23
mouse NFS-60 09/136 101.3 101300
Human GDNF 450-10
AF-450-10
human SH-SY5Y 09/266 0.78 780
Human GM-CSF 300-03
AF-300-03
human TF-1 88/646 12.8 12800
Human HGF 100-39 monkey 4MBr-5 96/564 0.21 210
Human IFN-β 300-02BC human TF-1 00/572 504 504000
Human IFN-γ 300-02
AF-300-02
human HT-29 87/586 1.94 1940
Human IGF-I 100-11
AF-100-11
mouse FDC-P1 91/554 .001 1
Human IGF-II 100-12
AF-100-12
mouse FDC-P1 96/538 0.6 600
Human KGF 100-19
AF-100-19
monkey 4MBr-5 03/150 2.33 2330
Human LIF 300-05
AF-300-05
human TF-1 93/562 12.2 12200
Human M-CSF 300-25
AF-300-25
mouse M-NSF-60 89/512 100 100000
Human β-NGF 450-01 human TF-1 93/556 0.53 530
Human PDGF-BB 100-14B
AF-100-14B
mouse Balb/c 3T3 94/728 2.65 2650
Human SCF 300-07 human TF-1 91/682 1.7 1700
Human TGF-β1 100-21
100-21C
AF-100-21C
mouse HT-2 89/514 9 9000
Human TGF-β3 100-36E
AF-100-36E
mouse HT-2 09/234 5.64 5640
Human TNF-α 300-01A mouse L929 12/154 39.1 39100
Human sTRAIL/Apo2L 310-04 human LN-18 04/166 1.45 1450
Human VEGF165 100-20
AF-100-20
HUVEC 02/286 0.69 690
Murine IL-2 212-12
AF-212-12
mouse CTLL-2 93/566 129 129000
Murine IL-3 213-13
AF-213-13
mouse NFS-60 91/662 132 132000
Murine IL-4 214-14
AF-214-14
mouse HT-2 91/656 19.8 19800
Murine IL-6 216-16
AF-216-16
mouse 7TD1 93/730 322 322000
Murine GM-CSF 315-03
AF-315-03
mouse FDC-P1 91/658 44.3 44300