Comparison of Isolation, Expansion and Cryopreservation Techniques to Produce Stem Cells from Human Exfoliated Deciduous Teeth (SHED) with Better Regenerative Potential.

Mesenchymal Stem Cells (MSCs) are adult stem cells that are gaining worldwide attention for their multi-potential use in tissue engineering-based regenerative medicine. They can be obtained from numerous sources and one of the excellent sources is the dental tissue, such as Stem cells that are extracted from the Human Exfoliated Deciduous teeth (SHED). SHED are considered ideal due to their inherent characteristics, including the capability to proliferate quickly with minimal oncogenesis risk, multipotency capacity and their ability to suppress the immune system. On top of these positive cell traits, SHED are easily accessible with the patient's safety assured, posing less ethical issues and could also provide a sufficient number of cells for prospective clinical uses. This is primarily attributed to their ability to differentiate into multiple cell linages, including osteoblasts, odontoblasts, neuronal cells, adipocytes, as well as endothelial cells. Albeit SHED having a bright future, there still remains an obstacle to develop reliable experimental techniques to retain the long-term regeneration potential of the stem cells for prospective research and clinical applications. Therefore, this review aims to describe the various isolation, expansion and cryopreservation techniques used by researchers in this stem cell field. Optimization of these techniques is crucial to obtain distinct SHED culture with preserved stem cell properties, which enable more reproducible results that will be the key for further stem cell therapy development.

Immune Responses to Influenza Virus and Its Correlation to Age and Inherited Factors.

Influenza viruses belong to the family Orthomyxoviridae of enveloped viruses and are an important cause of respiratory infections worldwide. The influenza virus is able to infect a wide variety species as diverse as poultry, marine, pigs, horses, and humans. Upon infection with influenza virus the innate immunity plays a critical role in efficient and rapid control of viral infections as well as in adaptive immunity initiation. The humoral immune system produces antibodies against different influenza antigens, of which the HA-specific antibody is the most important for neutralization of the virus and thus prevention of illness. Cell mediated immunity including CD4+ helper T cells and CD8+ cytotoxic T cells are the other arms of adaptive immunity induced upon influenza virus infection. The complex inherited factors and age related changes are associated with the host immune responses. Here, we review the different components of immune responses against influenza virus. Additionally, the correlation of the immune response to age and inherited factors has been discussed. These determinations lead to a better understanding of the limitations of immune responses for developing improved vaccines to control influenza virus infection.

Suppression of ERK1/2 and hypoxia pathways by four Phyllanthus species inhibits metastasis of human breast cancer cells.

Chemotherapies remain far from ideal due to drug resistance; therefore, novel chemotherapeutic agents with higher effectiveness are crucial. The extracts of four Phyllanthus species, namely Phyllanthus niruri, Phyllanthus urinaria, Phyllanthus watsonii, and Phyllanthus amarus, were shown to induce apoptosis and inhibit metastasis of breast carcinoma cells (MCF-7). The main objective of this study was to determine the pathways utilized by these four Phyllanthus species to exert anti-metastatic activities. A cancer 10-pathway reporter was used to investigate the pathways affected by the four Phyllanthus species. Results indicated that these Phyllanthus species suppressed breast carcinoma metastasis and proliferation by suppressing matrix metalloprotein 2 and 9 expression via inhibition of the extracellular signal-related kinase (ERK) pathway. Additionally, inhibition of hypoxia-inducible factor 1-α in the hypoxia pathway caused reduced vascular endothelial growth factor and inducible nitric oxide synthase expression, resulting in anti-angiogenic effects and eventually anti-metastasis. Two-dimensional gel electrophoresis identified numerous proteins suppressed by these Phyllanthus species, including invasion proteins, anti-apoptotic protein, protein-synthesis proteins, angiogenic and mobility proteins, and various glycolytic enzymes. Our results indicated that ERK and hypoxia pathways are the most likely targets of the four Phyllanthus species for the inhibition of MCF-7 metastasis.