The article presents a biographic report of Аlexander Уakovlevich Friedenstein's life and scientific research. А.Уa.Friedenstein is a world-known Russian scientist who was the first to describe and prove the presence of stem stromal cells within the stroma of hemopoietic organs.
The review deals with recent data on molecular mechanisms of migration and colonization of tissues and organs by stem cells, cellsprecursors. /n this direction the scientific literature emphasizes recently-described molecules stromal derived factor-1 {SOF-1) and its receptor {CXCR4).
The efficiency of transient expression of lacZ and gfp genesreporters under control of two different promoter elements of drozophyla hsp70 thermal shochk gene in transgeneic larva of Fo generation loach Misgurnus fossilis L. were studied. The expression of genes in early larva and in the prelarval stage was mosaic and depended upon the amount of genetic material introduced.
At the same time gene expression did not depend upon external tempreture increase, i.e. it appeared without thermal shock.
In 2-3 day larva the efficiency of transient expression was maximal and reached 100% in separate experimental series. Thus, regulatory elements of drozophula thermal shock gene are capable to provide constitutional expression of gene-reporter in loach larva.
The investigation was aimed to establish conditions for isolation and culturing cells of cartilaginous tissue procured from different sources.
Methods of chondrocytes obtaining and cultureing were compared. The chondrocytes were procured from human fetal cartilaginous tissue and the spinal column of patients with idiopathic scoliosis, as well as intervertebral disks of a new-born dog backbone.
The investigations of obtaining and culturing of chondrocytes from different sources showed that using collagenase solutions during 12-16 h at 37°С with continuous interfusion allowed to receive cells suspension with more than 90% viability. The maximal amount of viable chondrocytes was derived while segregating cells using 0.15% collagenase. Нuman fetal cartilaginous tissue and that of dog intervertebral disks is being dissociated in collagenase for 5-8 h, tissue from the spinal column of patients with idiopathic scoliosis for 18-20 h.
While culturing human fetal chondrocytes had the best proliferating capability. The culture of chondrocytes from the spinal column of idiopathic scoliosis patients had low proliferation index and a short culturing time as compared with fetal culture.
Using a simple model in vitro the capability of rabbit bone marrow stromal cells to respond to chemotaxic stimulus by guiding migration and growth of the colony was substantiated. As a source of chemotaxic stimulus vital and devitalized laminar bone tissue fragments autogenic to cells culture were used. It has been stated that under cellular culture conditions stromal cells respond largely to vital tissue signals which might have been due to biological active substances produced by cells of a bone fragment. Obscure response of culture to devitalized bone tissue presence may have been due to bone tissue properties alteration after devitalization, in particular, alterations of intracellular matrix proteins.
Possible influence of different factors to cells culture migration has been discussed.
Mono- and polyphilament threads were obtained from biological active polysaccharide - chitin procured from Far East crab shell and North sea shrimp by means of «moisted» formation of solutions. These threads are reabsorbed to N-acethilglucosamin and glucosamin while being acted upon by lizothim.
The investigation of monophilaments in cells culturing showed that they retained the characteristics of deformity and endurance.
Some samples were handmade by weaving from nonlisle polyphilament threads that were used to culture normal fibroblasts of human skin. The results enable positive conclusions to be made about the possibility of dermal fibroblasts growing on woven matrix of chitin fibers.