Stimulatory effect of helium-neon laser irradiation on human umbilical vein endothelial cells

Low-level laser irradiation [LLLI] has been shown to modulate the proliferation of endothelial cells. Helium-neon [He-Ne] laser is the best type of laser for biostimulation. The aim of the present study was to investigate the direct stimulatory effect of LLLI on the proliferative potential of human umbilical vein endothelial cell line in vitro. This study included five groups: group I [zero time after seeding He-Ne laser irradiation], group II [24 h after seeding He-Ne laser irradiation], group III [48 h after seeding He-Ne laser irradiation], group IV [96 h after seeding He-Ne laser irradiation], and group V [cumulative He-Ne laser irradiation every 48 h for a period of 6 days]. Each group was subdivided into three subgroups: subgroup a [control], subgroup b [1.77 J/cm[2]He-Ne laser irradiation], and subgroup c [3.54 J/cm[2] He-Ne laser irradiation]. A continuous wave He-Ne laser, emitting a wavelength of 632.8 nm with a power output of 5 mW was used for irradiating the cells. A growth curve was constructed for each group to determine the growth parameters. The most efficient cellular response to LLLI was in subgroup Ic depending on the population doublings achieved, followed by subgroup Ib. Therefore, the early the use of He-Ne laser irradiation for the cultured cells, the more the cellular stimulation and proliferation. Meanwhile, their delayed use resulted in less cellular stimulation and proliferation. Moreover, the results showed that 1.77 and 3.54 J/cm[2] of He-Ne laser irradiation were always stimulatory for endothelial cells either significantly or insignificantly. The present study showed that 1.77 and 3.54 J/cm[2] of He-Ne laser irradiation stimulated human umbilical vein endothelial cell line proliferation

Culture and characterization of human umbilical vein endothelial cells

Endothelial cells, the lining cells of blood vessels, are involved in many physiological and pathophysiological processes, including haemostasis, vasoregulation, inflammation, angiogenesis, and the extravasation of fluids, macromolecules, hormones, and leucocytes. This work was carried out to investigate the isolation, culture and characterization of human umbilical vein endothelial cells [HUVECs] in vitro and also to improve the cell yield and growth of these cells in culture. The endothelial cells were isolated by collagenase digestion and were seeded in tissue culture flasks using Dulbecco's modified Eagles medium [DMEM]. This study showed that the HUVECs were attached completely after 24 hour and became confluent after 5 days in vitro. The HUVECs displayed cobblestone morphology at confluence with granular cytoplasm. Immunohistochemically, these cells were positively stained using CD34 monoclonal antibody. The cells produced from this technique grew well for extended periods and retained the normal characteristics of primary HUVECs, making them invaluable tools for researches