#phagosome

Propaganda!

The regulatory T cells (Tregs), formerly known as suppressor T cells, are a subpopulation of T cells that modulate the immune system, maintain tolerance to self-antigens, and prevent autoimmune disease.

Making Connections

Macrophages are cells of the immune system, well known for engulfing and destroying pathogens or damaged cells, in a process called phagocytosis. Yet they also play a more constructive role during development, helping to build sophisticated networks in the kidneys. These organs regulate blood composition and filter out waste from the bloodstream to excrete as urine, thanks to a complex arrangement of carefully-structured minute tubules known as nephrons, closely associating with blood vessels. Pictured in a mouse embryo’s kidney, macrophages (in red) interact with blood vessels (in green) early on in development, helping to refine the position of kidney structures and encouraging connections between blood vessels. When macrophages were experimentally removed from developing kidneys, fewer connections formed. Understanding the role of macrophages may help produce more realistic kidney-mimicking organoids in the laboratory, for study and drug testing, and may even suggest future therapies targeting macrophages to treat kidney disease.

Written by Emmanuelle Briolat

Image from work by David A.D. Munro and colleagues

Centre for Discovery Brain Sciences, The University of Edinburgh, Edinburgh, UK

Image originally published under a Creative Commons Licence (BY 4.0)

Published in eLife, February 2019

Trapping TB

Tuberculosis (TB) gets its name from the bacterium that causes it, Mycobacterium tuberculosis. Despite being curable, it remains a global health threat and has become resistant to many antibiotics. Using real-time live-cell imaging, scientists have uncovered a defence mechanism within TB-infected cells that regulates infection. Usually, TB (in green) is detected by immune cells called macrophages (nuclei shown in blue), which then envelop the bacterium in cell membrane and ingest it, forming phagosomes (red rings). In a bid to survive, the bacteria punch holes in the phagosome membrane, and leak out into the cell to feed off its nutrients. However, the macrophages are sometimes able to counteract this, thanks to the actions of the Rab20 protein. Rab20 instructs the cell to send more membrane to tight phagosomes to make them more spacious. By enlarging the phagosomes, the bacteria are immobilised, allowing the delivery of antibacterial agents to destroy them.

Written by Soumya Perinparajah

Image by Laura Schnettger, Francis Crick Institute, London, UK

Francis Crick Institute, London, UK

Image copyright held by the original authors

Research published in Cell, Host and Microbe, May 2017

brutte cose... ma c'è della gente che non ha bisogno di stimoli, è proprio così di default

Grancereale <3

ODDIOOO, COME TI CAPISCO… una sera, anni orsono, ero andata a mangiare fuori, e una tizia ebbe il coraggio di farsi portare una pizza “ananas e bresaola”… … GESU’.