Nico Cerletti

Separation, purification, and sequence identification of TGF-β1 and TGF-β2 from bovine milk

Cox and Bürk (Eur. J. Biochem., 1991) reported the partial characterization of Milk Growth Factor (MGF) which stimulated the migration of fibroblasts. We have fractionated the partially purified sample by RP-HPLC and obtained the separation of two peaks of activity. The two active components were isolated as pure MGF-a and MGF-b by RP-HPLC and preparative SDS-PAGE. The purified MGF-a, consisting of a single band by gel electrophoresis and a single peak on an HPLC reversed-phase C-4 column, has the same specific activity as TGF-β2 in the fibroblast migration assay. MGF-a was digested by endoprotease Asp-N and the cleaved peptides were analyzed by Edman degradation and plasma desorption mass spectrometry (PDMS). The whole sequence of MGF-a determined by automated sequenator and PDMS of S-pyridylethylated protein and selected fragments was found to be identical to that of TGF-β2. MGF-b protein mixture separated by SDS-PAGE was electrophoretically transferred onto a Biometra Glassybond membrane, and the blotted MGF-b protein was directly sequenced on an automated sequenator. The identified 29 amino acids sequence of MGF-b was identical to the amino-terminal sequence of TGF-β1. Our study demonstrates that MGF is composed of both TGF-β1 and TGF-β2. TGF-β2 (85%) is the predominant form.

Transforming growth factors type-β and dexamethasone attenuate group II phospholipase A2 gene expression by interleukin-1 and forskolin in rat mesangial cells

Treatment of rat mesangial cells with interleukin‐1β(IL‐1β) and forskolin induced, in a synergistic fashion,the expression of group II phospholipase A2 (PLA2) mRNA, with subsequent increased synthesis and secretion of PLA2. In contrast, interleukin‐6 did not increase PLA2 mRNA levels of PLA2 activity. Transforming growth factor (TGF) β1, TGFβ2 and TGFβ3 equipotently attenuated the IL‐1β‐ and forskolin‐induced elevation of PLA2 mRNA, as well as PLA2 synthesis and secretion. The glucocorticoid dexamethasone only partially suppressed the IL‐1β‐ and forskolin‐induced elevation of PLA2 mRNA, but totally inhibited PLA2 synthesis and secretion.

TGF-β: upregulator of HIV replication in macrophages

Abstract TGF-β at physiological concentrations, when added to monocyte-derived macrophages following HIV1 infection, has an enhancing effect upon the rate of virus production. This effect is observed with the monocytotropic isolate ADA, as well as with HIV1 IIIB, which poorly replicates in macrophages.

Wound healing in aged animals — Effects of locally applied Transforming Growth Factor beta 2 in different model systems

Local application of a growth factor which could stimulate cell turnover, extracellular matrix synthesis and blood vessel formation in the skin should improve and accelerate wound healing processes which are often impaired in old age. We demonstrate the effects of TGF-beta 2 in promoting wound repair in old animals where normal healing responses are shown to be naturally slower. The potential use of TGF-beta s for the treatment of wound injuries, including chronic non-healing ulcers in the elderly, is discussed.

Crystallization and preliminary X-ray analysis of recombinant human transforming growth factor β2

Recombinant human transforming growth factor β2 (TGF‐β2) was cloned and expressed in E. coli. The protein was isolated from inclusion bodies, renatured and purified to a single component as judged by reversed‐phase HPLC. The recombinant TGF‐β2 was shown to have a biological activity equal to that of native TGF‐β2 in a fibroblast migration assay. Pure, active recombinant TGF‐β2 has been crystallized from polyethylene glycol 400. The trigonal crystals of spacegroup P3121 or P3221 have unit cell dimensions of a=b=60.6 Å, c=75.2 Å and diffract beyond 2.0 Å.

Distribution of the Calcium-Binding Proteins MRP-8 and MRP-14 in Normal and Pathological Conditions: Relation to the Cystic Fibrosis Antigen

Eukaryotic cells require calcium ions for optimal growth and functioning. The intracellular actions of calcium as a biological second messenger appear to be the result of its interaction with a set of calcium-binding proteins referred to as calcium modulated proteins. (Persechini et al. 1989).