Comparison of Immune Cell Recruitment and Function in Endometrium During Development of Epitheliochorial (Pig) and Hemochorial (Mouse and Human) Placentas

Illustration of the estimated evolutionary time scale in millions of years (Myr) for development of the immune system and placental mammals (left) and for the phylogenetic clades of mammals (right). Self–non-self discrimination was the first immune trait to evolve. It used innate immune processes such as evolution of transplantation antigens (MHC) and receptor (R)-bearing Natural Killer (NK) cells. Appearance of the duplicated Recombinase activating genes (RAG1, RAG2) permitted somatic recombination and evolution of adaptive immunity. RAG1 and RAG2 are used by T and B lymphocytes to produce their wide ranges of exquisitely specific antigen surface receptors.

A list chemokines that bind to the decoy receptor molecules D6, DARC and CCX CKR. Some inflammatory chemokines bind to both D6 and DARC.

Photomicrographs of D6 decoy receptor expression (A), expression of CCL4, a D6 ligand (B) and an overlay to display receptor/ligand co-expression (C) in healthy gd50 paraffin-embedded porcine trophoblast. Sections were stained with rat anti-human D6 (R&D Systems) and anti-mouse and rat CCL4 (eBioscience Inc.) antibodies. D6: green; CCL4: red. Scale bar is 400μm. Inset (D) is negative control. Background reactivity is non-specific binding to RBCs. Scale bar is 200μm.