Inflammation switches the chemoattractant requirements for naive lymphocyte entry into lymph nodes.

Sustained lymphocyte migration from blood into lymph nodes (LNs) is important for immune responses. The CC-chemokine receptor-7 (CCR7) ligand CCL21 is required for LN entry but is downregulated during inflammation, and it has been unclear how recruitment is maintained. Here, we show that the oxysterol biosynthetic enzyme cholesterol-25-hydroxylase (Ch25h) is upregulated in LN high endothelial venules during viral infection.

Lymphoid tissue on the mind.

To surveil an organ for pathogens, lymphoid structures need to sample antigens locally. The full set of lymphoid structures involved in surveilling for brain-tropic pathogens has not been defined. Through comprehensive imaging of the mouse meninges, a new study by Fitzpatrick et al.

Symbiotic Synergy from Sponges to Humans: Microflora-Host Harmony Is Crucial for Ensuring Survival and Shielding against Invading Pathogens.

Gut microbiota plays several roles in the host organism's metabolism and physiology. This phenomenon holds across different species from different kingdoms and classes. Different species across various classes engage in continuous crosstalk via various mechanisms with their gut microbiota, ensuring homeostasis of the host.