Comparative Morphological Study of the Formation of Reparative Regenerate during Skin Wound Healing in Rats under the Effect of Drugs and Bone Marrow.

We studied the formation of the reparative regenerate of the skin wound in rats under the effect of drug products based on keratan and secretome of bone marrow mesenchymal stem cells (MSC), as well as bone marrow cells (native and exposed to laser radiation with a wavelength of 1.56 µm). Due to the biological affinity for the dermal tissue, keratan preparations being applied to the skin stimulate regeneration of the wound defect. This substance in the form of a gel is characterized by high diffusion capacity, penetrates into the deeper layers of the dermis, and promotes the growth of the granulation tissue. Application of an ointment prepared on the basis of MSC secretome promotes quick transition of the healing process from the inflammatory to the regenerative stage. Thus, bone marrow cells were successfully used for skin wound healing. The results of the use of bone marrow cells for the healing of skin wounds were successful; bone marrow exposed to laser radiation demonstrated high efficiency in promoting reparative processes.

Reconstruction of Ligament and Tendon Defects Using Cell Technologies.

We studied the possibility of restoring the integrity of the Achilles tendon in rabbits using autologous multipotent stromal cells. Collagen or gelatin sponges populated with cells were placed in a resorbable Vicryl mesh tube and this tissue-engineered construct was introduced into a defect of the middle part of the Achilles tendon. In 4 months, histological analysis showed complete regeneration of the tendon with the formation of parallel collagen fibers, spindle-shaped tenocytes, and newly formed vessels.

Effects of acoustic and EHF impulses on multipotent stromal cells during formation of bone marrow containing heterotopic organs in tissue engineered constructions.

We studied the effects of physical factors (acoustic impulses of laser-induced hydrodynamics, AILIH, and EHF-radiation) on the formation of heterotopic bone marrow organs. Suspension of precipitated mouse bone marrow cells was exposed to AILIH and EHF or their combinations (AILIH+EHF, EHF+AILIH). The developed tissue engineering constructions (gelatin sponges containing 107 nucleated bone marrow cells exposed to physical factors) were transplanted under the renal capsule of syngeneic mice. Analysis of newly formed hemopoietic organs was performed after 3 and 5 months. The total amount of hemopoietic cells, number of multipotent stromal cells, efficiency of colony formation from these cells, and weight of bone capsule of the transplants were measured. Microscopic study showed that 5-month transplants were significantly larger than 3-month transplants and contained 3-fold more hemopoietic cells (20-fold in the AILIH+EHF group). The number of multipotent stromal cells was maximum in EHF+AILIH group (by 2.2 times higher than in the control) and minimum in AILIH+EHF group. Exposure to EHF+AILIH had most pronounced effect on the formation of the bone marrow transplants. The weight of bone capsules more rapidly increased in gelatin sponges of 3-month transplants of EHF+AILIH and AILIH groups. These data suggest that the studied physical factors can be used for acceleration of rehabilitation process.

[Isolation and characteristics of the bacteriophage from the vaccine strain Tohama phase I]. / Vydelenie i kharakteristika bakteriofaga iz vaktsinnogo shtamma Tohama I fazy.

Some properties of bacteriophage phi T isolated from the vaccine strain Bordetella pertussis Tohama phase I and propagated in Bordetella parapertussis 504 cells are presented. Phage phi T belongs to the IV group in accordance with Tikhonenko classification. The diameter of head and length of noncontractile tail sheath are 49.5 +/- 0.5 and 145 +/- 7 nm, respectively. Diameter of the tail sheath is 3.2 +/- 0.6 nm. Molecular mass of the phage DNA is 37 +/- 3 kb. Population of phi T phage is polymorphous and consists of particles the genomes or which vary from each other by the "insert" located 6.8 +/- 0.6 kb from the end of molecule. The blot hybridization has demonstrated that the bacteriophage genome is not inserted into the chromosome of the lysogenic strain. Autonomous location of the phage genome in the host cell is suggested. The temperature and hydrogen ions concentration effects on bacteriophage phi T stability were studied. The conditions for phage suspension storage are described.

[Lysogeny and conversion characteristics of microbes in the genus Bordetella]. / Osobennosti lizogenii i konversii u mikrobov roda Bordetella.

The genomes of B. pertussis bacteriophages 134 and 41405 and B. bronchiseptica bacteriophage 214 have been studied. As revealed by the methods of heteroduplex and restriction analyses, the populations of these bacteriophages are heterogeneous and their DNAs differ in size and location of inserts. The study carried out with the use of blot hybridization techniques has shown that in lysogenic cells the genome is not integrated into the chromosome, but exists as an autonomous plasmid replicon. Only partial incorporation of the phage genome into the recipient chromosome takes place in the process of conversion, the phage genome continuing its existence as an autonomous replicon.

Bone marrow stromal colony formation requires stimulation by haemopoietic cells.

In mouse bone marrow cultures plated at low cell density, stromal colonies formed from colony-forming unit fibroblastic (CFUf) failed to develop unless the cultures were supplemented with irradiated feeder cells. Colony-stimulating activity was produced by irradiated bone marrow and spleen cells and by platelets, was dose dependent, not species specific and was maximal at high serum concentration. The efficiency of CFUf colony formation was 1.7 x 10(-4) for mechanically disaggregated and 14.6 x 10(-4) for trypsinised bone marrow cells. The colonies formed in the presence of feeder cells comprised hundreds of fibroblasts. In the absence of feeder cells, small fibroblast foci and single fibroblasts only were present in cultures. PDGF, IL-3 and EGF did not substitute for the colony-stimulating activity of feeder cells. These results suggest that CFUf colony formation requires growth factor(s) released by platelets and megakaryocytes which remain to be identified.

[The dependence of the formation of stromal CFU-f colonies on the stimulating action of hematopoietic cells]. / Zavisimost' obrazovaniia stromal'nykh KOKf-kolonii ot stimuliruiushchego vozdeistviia gemopoéticheskikh kletok.

CFU-f-derived stromal colony formation was accomplished in adherent marrow cell cultures (AMCC) with serum-rich medium. It turned out to require additional stimulation by hemopoietic feeder cells: by irradiated marrow cells and spleen cells if they possess megakaryocytes and platelets or by platelets from the blood. PDGF, EGF and IL-3 did not substitute the colony stimulating activity of feeder cells. Thymus, lymph node cells and blood leucocytes had no colony stimulating activity. At low oxygen concentrations which improve colony formation the stimulating activity of hemopoietic feeder cells was expressed, as well. Thus, CFU-f colony formation depends on stimulation by hemopoietic cells in addition to serum growth factors. In full populations of marrow cells the CFU-f colony formation is stimulated by marrow cells which accompany the CFU-f.

Bacteriophages of Bordetella sp.: features of lysogeny and conversion.

It has been the purpose of this paper to study molecular-biological features of the Bordetella bacteriophage interaction with the host cell during lysogeny and conversion as well as to determine the degree of homology between genomes of homologous and heterologous bacteriophages. Genomes of bacteriophages from B. pertussis 134, 41405 and B. bronchiseptica 214 were studied. Heteroduplex and restriction analyses revealed a heterogeneity of bacteriophage populations, and their DNAs were found to differ in size and position of inserts. As shown by blot hybridization, the bacteriophage genome is not inserted into the chromosome of the lysogenic cell but apparently exists as an autonomous plasmid replicon. It has been established that during conversion only a part of the phage genome is inserted into the chromosome of the recipient cell.