Regulation of T cell activation by CD28 family New and Updated Topics and Pathways. Topics with new or revised pathways in this release include Cellular responses to stimuli ( Mechanical load activates signaling by PIEZO1 and integrins in osteocytes ), Developmental Biology ( Developmental Lineage of Pancreatic Acinar Cells and MITF-M-regulation melanocyte development ), DNA Replication ( Strand-asynchronous mitochondrial DNA replication ), Extracellular matrix organization ( Formation of the dystroglycan-associated glycoprotein complex (DGC) ), Immune system ( Co-inhibition by BTLA , Co-inhib