Immune cells that serve as antibody production factories, also known as plasma cells, are the focus of a recent Nature Immunology paper from Jeremy Boss and colleagues.

Plasma cells also appear in Ali Ellebedy and Rafi Ahmed’s recent paper on the precursors of memory B cells and Eun Lee’s work on long-lived antibody-producing cells. In addition, plasma cells appear prominently in Larry Boise’s studies of myeloma, because myeloma cancer cells are thought to come from plasma cells and have a similar biology.

The Boss lab’s paper focuses on patterns of methylation, modifications of DNA that usually help turn genes off. In comparison with resting B cells, plasma cells need to turn on lots of genes, so their DNA methylation level goes down when differentiation occurs (see graph). PC = plasma cells, PB = plasmablasts. DNAme indicates the extent of DNA methylation.

When genes are turned off by methylation, the DNA is surrounded by repressive chromatin: proteins that block access by RNA polymerase. In this paper, the researchers outline which regulatory factors play pioneering roles in removing the repressive chromatin and excavating genes that are going to be turned on.

GMB graduate student Benjamin Barwick, who defended his thesis this summer, is first author. Boss is chair of the Microbiology and Immunology department and Associate Dean for Basic Research.