The Effects of Mycoplasma Contamination upon the Ability to Form Bioengineered 3D Kidney Cysts

Mycoplasma contamination of cell cultures is a pervasive, often undiagnosed and ignored problem in many laboratories that can result in reduced cell proliferation and changes in gene expression. Unless contamination is specifically suspected, it is often undetected in two dimensional (2D) cultures and the resulting effects of mycoplasma contamination are rarely appreciated and can lead to incorrect conclusions. Three dimensional (3D) tissue cultures are increasingly utilized to explore tissue development and phenotype. However, 3D cultures are more complex than 2D cell cultures and require a more controlled cellular environment in order to generate structures necessary to mimic in vivo responses and are often maintained for longer time periods. Changes to the microenvironment are assumed to have a more extreme effect upon the success of 3D tissue cultures than 2D cell cultures, but the effects of mycoplasma have not been studied. To test this hypothesis, we grew 2D cell cultures and 3D tissues from pig kidney epithelial cells (LLC-PK1) that were contaminated with mycoplasma and the same stock of cells after mycoplasma removal. We did not observe an effect of mycoplasma contamination on proliferation in 2D monolayer cell culture. However, cyst formation in 3D tissues was altered, with effects upon the number, size and structure of cysts formed. These data serve to reinforce the necessity of testing cell stocks for mycoplasma contamination.     

Midkine and Pleiotrophin Concentrations in Amniotic Fluid in Healthy and Complicated Pregnancies

BackgroundMidkine (MDK) and pleiotrophin (PTN) are heparin-binding growth factors that, in rodents, are highly expressed in early life and decrease to undetectable levels by adulthood. The potential roles of MDK and PTN in human growth and development are not completely elucidated.ConclusionThe concentration of MDK but not that of PTN declined with gestational age. Both MDK and PTN concentrations were found to be lower in pregnancies that were complicated by chorioamnionitis at term, raising the possibility that these growth factors might be useful as markers for infection.     

Hempseed protein hydrolysates’ effects on the proliferation and induced oxidative stress in normal and cancer cell lines

Food proteins from different sources can provide beneficial effects on human health by releasing the bioactive peptides that are integral part of their native structure. In this study, we tested the biological potential of hempseed protein hydrolysates (HPHs) obtained from hempseed cake protein isolate. The HPHs were prepared by enzyme hydrolysis using three different proteases of microbial origin: Alcalase®, Neutrase® and Protamex®. The antioxidant activity of the obtained hydrolysates was determined by oxygen radical absorbance capacity (ORAC) assay, while the proliferative effects on normal (HaCaT) and cancer (HeLa) cells were determined by the CellTiter 96^® AQ_ueous One Solution Reagent (MTS) assay. HPHs showed dose-dependent antiproliferative effects on HeLa cells and stimulatory effects on the proliferation of HaCaT cells. HPH obtained by Neutrase^® (HPH-N) showed the highest antioxidant activity expressed as an ORAC value. The protective effect of HPH-N on H₂O₂-induced oxidative stress in normal and cancer cells was evaluated and 1 mg/mL of HPH-N significantly reduced the formation of intracellular reactive oxygen species (ROS) in both cell lines. The obtained results indicate the benefits of HPHs as potential natural antioxidants for the food industry and contribute to the growing trend of utilizing hempseed by-products.