Advance of Ser/Thr Kinase Pololike Kinase 1 (Plk1) Research / 中国生物工程杂志

Pololike kinase 1(Plk1)contain an Nterminal Ser/Thr kinase catalytic domain and a Cterminal region that contains two poloboxes.As a key regulator of multiple steps during cell cycle across eukaryotic species,many proteins interact with Plk1.Plk1 is highly expressed in malignant cells and serves as a negative prognostic marker in specific human cancer types.Plk1 is a potential target for cancer therapy.Some novel smallmolecule inhibitors of pololike kinase 1 provide novel opportunities for cancerdrug discovery,such as BI 2536,ON01910.

Collagen membrane as scaffold for the three-dimensional cultivation of cardiac cells in vitro / 生物工程学报

The objective of this study was to develop research of cardiac cells to reestablish 3D tissue architecture in vitro, we performed studies using collagen membrane as three-dimensional scaffold for cardiac cells culture with the principles and methods of tissue engineering. The polymer scaffold provides a 3-D substrate for cell attachment and tissue formation. Cardiac cells isolated by enzymatic digestion from 1d old neonatal rats were seeded to three-dimensional collagen scaffolds and tissue culture plates. The morphology, beating rate and the metabolic indexes, including specific consumption rate of glucose (q(glu)) , specific production rate of lactate (q(lac)), lactate transform rate ( Y(lac/glu)), specific creatine kinase (CK) and lactate dehydrogenase (LDH) activities of cardiac cells cultured on three-dimensional collagen membrane and tissue culture plates were compared. It was found that cells shape and cells' CK and LDH activity was no differences between 3D and 2D cultures and cell beat rate on cell culture cluster was slower than those cells cultured on collagen membrane, However the cell glucose consumption and lactate yield rate of cells cultured on cluster was higher than those cells cultured on collagen membrane. After 5 days of cultivation, cardiac cells cultured on collagen membrane scaffolds organized into three-dimensional (3D) aggregates as opposed to the two-dimensional (2D) aggregates mosaic pattern seen in tissue culture plates, and spontaneous and rhythmical contractile 3D cultures in unison were visible to the naked eye and the area of synchronous contract three-dimensional (3D) aggregates reaches 80cm2. The mean value of q(glu), q(lac) and Y(lac/glu) of cultured on three-dimensional collagen scaffold was 7.37 micromol/10(6) cells/d, 2.92 micromol/10(6) cells/ d and 0.38 micromol/micromol, versus 7.59 micromol/10(6)cells/d, 3.83 micromol/10(6) cells/d and 0.51 micromol/micromol in tissue culture plates. These results demonstrate that cardiac cells immobilized on collagen membrane in 3D cultures maintain similar metabolic activity and contractile function when compared with native cardiac cells. The above results support the idea that engineered cardiac tissue can be used as a model of native tissue for studies of tissue development and function in vitro and eventually for tissue repair in vivo.