069. CONJUNCTIVAL TISSUE  - Mast Cell 7000x 12mb

A Sight For Sore Eyes

  Have you ever experienced itchy, watery eyes as a result of seasonal allergies? The objects in this picture are to blame. This microscope image shows conjunctival tissue from an eye in the presence of a single mast cell. Mast cells are important regulators of the immune system. Upon invasion of the eye with foreign objects, such as allergens, the mast cell is recruited to … Continue reading A Sight For Sore Eyes

066. COLLAGEN 7.88mb

Holding the Fort Down

And how! Depicted here are intricate collagen fibers, the structural glue and the most abundant protein in the mammalian body. Collagen proteins occupy the extracellular space in connective tissues, and form fibers that provide the physical scaffold for holding and strengthening several tissues in the body including bones, ligaments, tendons, skin, and the cornea. With several different classes of this protein defined to date, type … Continue reading Holding the Fort Down

FlyNeuromuscularJunction

Branched synaptic arbor in fillet

The Drosophila neuromuscular junction is a beautiful and yet powerful model synapse for in vivo studies of development, physiology, cell biology and plasticity. This illustration by Saskia Van Vactor shows a field of ventral longitudinal body wall muscles in red, as if stained with phalloidin to highlight filamentous actin, the main protein building block of muscle. Against this background, several branches of intersegmental nerve extend … Continue reading Branched synaptic arbor in fillet

b7500_Connectome_ISN017_tube

The Brain is a Series of Tubes

The brain is made of up billions of neurons and even more connections between neurons. We can get an idea of how neurons are connected across the human brain using a type of brain scan called diffusion-weighted magnetic resonance imaging (dMRI). How does dMRI work? It actually measures the direction that water moves throughout the brain. Sometimes, water can move in all directions equally easily – like … Continue reading The Brain is a Series of Tubes

GFAP-Coronin1a Yu Wang

Retinal Corona

Image contributed by Yu Wang, a third year graduate student at Harvard Medical School. Glial cells support the proper function of neuronal cell types and are also responsible for cleaning up cell debris such as leftover neurotransmitter molecules (what neurons use to communicate with each other). Certain types of glia, called microglia, function as the first line of defense in immune-privileged places such as the … Continue reading Retinal Corona

044, BPAE CELLS - cryo-lysed 2.65mb

Cryolysed

This is a layer of epithelial cells that was subjected to sever freeze-thaw cycles before being imaged at 400x magnification, which caused the membranes to rupture and form these arrays of crystal-like structures. When frozen, the water inside the cells expands, breaking through the cell membrane. With the membrane integrity compromised, when the cells are thawed the water inside leaks out, the fragments of membrane form aggregates, … Continue reading Cryolysed