Yin and yang of immunological memory in controlling infections: Overriding self defence mechanisms.

Immunological memory is critical for host immunity and decisive for individual to respond exponentially to previously encountered infection. Both T and B cell memory are known to orchestrate immunological memory with their central and effector memory arms contributing in prolonged immunity/defence mechanisms of host. While central memory helps in maintaining prolonged immunity for a particular infection, effector memory helps in keeping local/seasonal infection in control. In addition to this, generation of long-lived plasma cells is pivotal for generating neutralizing antibodies which can enhance recall and B cell memory to control re-infection. In view of this, scaling up memory response is one of the major objectives for the expected outcome of vaccination. In this line, this review deals with the significance of memory cells, molecular pathways of their development, maintenance, epigenetic regulation and negative regulation in various infections. We have also highlighted the significance of both T and B cell memory responses in the vaccination approaches against range of infections which is not fully explored so far.[Box: see text].

Biosynthesis of Zinc Oxide Nanoparticles Using Catharanthus Roseus Leaves and Their Therapeutic Response in Breast Cancer (MDA-MB-231) Cells.

As the current study reports the utilization of the leaf extract of Catharanthus roseus (C.roseus) for the biological synthesis of zinc oxide nanoparticles (ZnO NPs) because of the importance of the importance of health and environment. Bioinspired synthesis were characterized using Fourier Transform Infrared Spectroscopy (FT-IR), Field Emission-Scanning Electron Microscopy (FE-SEM), Transmission Electron Microscopy (TEM), Energy-Dispersive X-ray Spectroscopy (EDX) and X-Ray diffraction (XRD). XRD and TEM micrograph analysis revealed that the synthesized nanostructures were well-dispersed and spherical with the average particle size in the 18-30 nm range were produced. The FT-IR spectra confirmed presence of phenolic compounds that act as reducing and capping agents. Further, it suggested the possible utilization of hydroxyl groups and amides in the reduction of Zn ions and stablization of ZnO NPs. Zinc oxide nanomaterials are effective in cancer treatments, including the destruction of tumor cells with minimal damage to healthy cells. The toxicity of zinc oxide nanomaterials was checked in vitro in the human breast cancer line MDA-MB-231. Inverse relation of the percentage of viable cells to the concentration of zinc oxide nanomaterials at increasing molar levels was assessed. The cytotoxicity analysis used in the MTT test shows the substantial viable MDA-MB-231-cells despite the increased concentration of exposure to zinc oxide nanomaterials. Reduction in the ratio of viable MDA-MB-231 cells after being exposed to zinc oxide nanomaterials was compared to untreated cancerous cells. The present approach to biosynthesis is quick, inexpensive, eco-friendly, and high-rise stable nanomaterials of zinc oxide with substantial cancer potential. This is the first study that reports molar concentrations (with the lowest concentration of 10 mM) as an anticancer agent for breast cancer and potential clinical uses for synthesized zinc oxide nanomaterials. Thus, C. roseus based synthesized ZnO NPs could be explored not only as environmentally benign method but also as a potential anti-carcinogenic agent.

Molecular Mechanisms of Action of Tocotrienols in Cancer: Recent Trends and Advancements.

Tocotrienols, found in several natural sources such as rice bran, annatto seeds, and palm oil have been reported to exert various beneficial health promoting properties especially against chronic diseases, including cancer. The incidence of cancer is rapidly increasing around the world not only because of continual aging and growth in global population, but also due to the adaptation of Western lifestyle behaviours, including intake of high fat diets and low physical activity. Tocotrienols can suppress the growth of different malignancies, including those of breast, lung, ovary, prostate, liver, brain, colon, myeloma, and pancreas. These findings, together with the reported safety profile of tocotrienols in healthy human volunteers, encourage further studies on the potential application of these compounds in cancer prevention and treatment. In the current article, detailed information about the potential molecular mechanisms of actions of tocotrienols in different cancer models has been presented and the possible effects of these vitamin E analogues on various important cancer hallmarks, i.e., cellular proliferation, apoptosis, angiogenesis, metastasis, and inflammation have been briefly analyzed.