Recombinant Human Transforming Growth Factor

Transforming Growth Factor-beta (TGF-beta1) is a member of a superfamily of homologous, disulfide-linked, homodimeric proteins that regulate the proliferation and differentiation of normal and transformed cells. Human TGF-beta1 is a 25.0 kDa protein with each subunit containing 112 amino acid residues. The source is Baculovirus infected High-5 cells. The formulation is lyophilized from Sodium Citrate, pH 3.5 buffer.

The lyophilized TGF-beta1, though stable at room temperature, is best stored desiccated below 0°C. Reconstituted stock solutions of TGF-beta1 (20 µg/ml in citrate buffer) can be stored at room temperature or 4°C for at least two months. More dilute solutions of TGF-beta1 in PBS/albumin should be stored at -20°C. Purity is greater than 98% by SDS-PAGE and HPLC analyses. Endotoxin level is less than 0.1 ng per µg (1EU/µg) of TGF-beta1.

Human TGF-beta1 is very soluble in buffers at pH's below 4. However, at neutral pH's TGF-beta1 tends to stick to surfaces of tubes, pipets, etc. PeproTech's TGF-beta1, when reconstituted in water to a concentration of 20 µg/ml (e.g., 2 µg/100 µl), will yield a solution of 5 mM citrate buffer pH 3.5 that can be stored at room temperature or 4°C for at least two months. Dilution of this stock solution should take into account the stickiness of the protein. It is recommended that further dilutions be made into PBS containing 2 mg/ml albumin.

Biological activity is determined by its ability to inhibit the mouse IL-4-dependent proliferation of mouse HT-2 cells. The ED₅₀ was found to be <0.05ng/ml, corresponding to a specific activity of 2 x 10⁸ units/mg. Usage is for research use only, not diagnostic or therapeutic procedures.

PeproTech, Inc., Princeton Business Park, 5 Crescent Ave., G2 Rocky Hill, NJ 08553. Tel: 609-497-0253; Fax: 609-492-0321.