Before the cardiologist goes nuclear w/ stress #AHA17

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Virus hunting season open

Previously unknown viruses, identified by Winship + UCSF scientists, come from a patient with a melanoma that had metastasized to the Read more

#AHA17 highlight: cardiac pacemaker cells

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B cells

Plasma cells, antibody factories

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.B cell methylation

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. Read more

Posted on by Quinn Eastman in Immunology Leave a comment

Decoding lupus using DNA clues

People with systemic lupus erythematosus can experience a variety of symptoms, such as fatigue, joint pain, skin rashes and kidney problems. Often the symptoms come and go in episodes called flares. In lupus, the immune system goes haywire and produces antibodies that are directed against the body itself.

A team of Emory scientists has been investigating some fundamental questions about lupus: where do the cells that produce the self-reactive antibodies come from? Are they all the same?

In the accompanying video, Kelli Williams, who helps study the disease and has lupus herself, describes what a flare feels like. In addition, Emory researchers Iñaki Sanz, MD and Chris Tipton, PhD explain their findings, which were published this summer in Nature Immunology.

Judging by the number and breadth of abstracts on lupus at the Department of Medicine Research Day (where Tipton won 1st place for basic science poster), more intriguing findings are in the pipeline. Goofy Star Wars metaphors and more explanations of the science here.

Posted on by Quinn Eastman in Immunology Leave a comment

Max Cooper celebrated in Nature for 50 yrs of B cells

Emory’s Max Cooper was celebrated this week in Nature for his discovery of B cells in the 1960s, while working with Robert Good at the University of Minnesota.

Cooper in Good’s laboratory in the 1960s (source: National Library of Medicine)

B cells are immune cells that display antibodies on their surfaces, and can become antibody-secreting plasma cells. Without B cells: no antibodies to protect us against bacteria and viruses. Where B cells come from, and how they can develop such a broad repertoire of antibody tools, was a major puzzle of 20th century immunology, which Cooper contributed to solving. (See the Nature piece to learn why the “B” comes from the name of an organ in chickens.)

The authors did not mention that Cooper is now at Emory studying lampreys’ immune systems, which are curiously different from those of mammals. The similarities and differences provide insights into the evolution of our immune systems. In addition, scientists here are exploring whether lamprey’s antibody-like molecules might be turned into anticancer drugs.

Posted on by Quinn Eastman in Immunology Leave a comment

Present at the creation: immunology from chickens to lampreys

You can get far in biology by asking: “Which came first, the chicken or the egg?” Max Cooper discovered the basis of modern immunology by asking basic questions.

Cooper was selected for the 2012 Dean’s Distinguished Faculty Lecture and Award, and on Thursday evening dazzled an Emory University School of Medicine audience with a tour of his scientific career. He joined the Emory faculty in 2008 as a Georgia Research Alliance Eminent Scholar.

Max Cooper, MD

Cooper’s research on the development of the immune system, much of it undertaken before the era of cloned genes, formed the underpinnings of medical advances ranging from bone marrow transplants to monoclonal antibodies. More recently, his research on lampreys’ divergent immune systems has broadened our picture of how adaptive immunity evolved.

Cooper grew up in Mississippi and was originally trained as a pediatrician, and became interested in inherited disorders that disabled the immune system, leaving children vulnerable to infection. He joined Robert Good’s laboratory at the University of Minnesota, where he began research on immune system development in chickens.

In the early 1960s, Cooper explained, scientists thought that all immune cells developed in one place: the thymus. Working with Good, he showed that there are two lineages of immune cells in chickens: some that develop in the thymus (T cells) and other cells responsible for antibody production, which develop in the bursa of Fabricius (B cells). [On Thursday, he evoked chuckles by noting that a critical discovery that drove his work was published in the journal Poultry Science after being rejected by Science.]

Cooper moved on to the University of Alabama, Birmingham, and there made several discoveries related to how B cells develop. A collaboration with scientists at University College, London led to the identification of the places where B cells develop in mammals: fetal liver and adult bone marrow.

Cooper’s research on lampreys began in Alabama and has continued after he came to Emory in 2008. Primitive lampreys are thought to be an early offshoot on the evolutionary tree, before sharks, the first place where an immune system resembling those of mammals and birds is seen. Lampreys’ immune cells produce “variable lymphocyte receptors” that act like our antibodies, but the molecules look very different in structure. These molecules were eventually crystallized and their structure probed, in collaboration with Ian Wilson in San Diego.

Lampreys have variable lymphocyte receptors, which resemble our antibodies in function but not in structure

Cooper said he set out to figure out “which came first, T cells or B cells?” but ended up discovering something even more profound. He found that lampreys also have two separate types of immune cells, and the finding suggests that the two-arm nature of the immune system may have preceded the appearance of the particular features that mark those cells in evolution.

 

 

 

Posted on by Quinn Eastman in Immunology 1 Comment