Precision medicine with multiple myeloma

“Precision medicine” is an anti-cancer treatment strategy in which doctors use genetic or other tests to identify vulnerabilities in an individual’s cancer subtype. Winship Cancer Institute researchers have been figuring out how to apply this strategy to multiple myeloma, with respect to one promising drug called venetoclax, in a way that can benefit the most patients. Known commercially as Venclexta, venetoclax is already FDA-approved for some forms of leukemia and lymphoma. Researchers had observed that multiple Read more

Promiscuous protein droplets regulate immune gene activity

Biochemists at Emory are achieving insights into how an important regulator of the immune system switches its function, based on its orientation and local environment. New research demonstrates that the glucocorticoid receptor (or GR) forms droplets or “condensates” that change form, depending on its available partners. The inside of a cell is like a crowded nightclub or party, with enzymes and other proteins searching out prospective partners. The GR is particularly well-connected and promiscuous, and Read more

Neutrophils flood lungs in severe COVID-19

In the lungs of severe COVID-19 patients, neutrophils camp out and release inflammatory cytokines and tissue-damaging Read more

cardiac pacemaker cells

Overcoming cardiac pacemaker “source-sink mismatch”

Instead of complication-prone electronic cardiac pacemakers, biomedical engineers at Georgia Tech and Emory envision the creation of “biological pacemakers.” Hee Cheol Cho and colleagues have been taking advantage of his work on a gene called TBX18 that can reprogram heart muscle cells into specialized pacemaker cells.

Graduate student Sandra Grijalva in lab

Every heartbeat originates from a small group of cells in the heart called the sinoatrial node. How these cells drive contractions in the relatively massive, and electrically sturdy, rest of the heart is a problem cardiology researchers call the “source-sink mismatch.” Until Cho’s innovations, it was only possible to isolate a handful of pacemaker cells from animal hearts, and the isolated cells could not be cultured.

Cho and colleagues recently published a paper in Advanced Science describing TBX18-induced pacemaker cell spheroids, a platform for studying source-sink mismatch in culture

Graduate student Sandra Grijalva is the first author of the paper. We first spotted Grijalva’s work when it was presented at the American Heart Association meeting in 2017. Read more

Posted on by Quinn Eastman in Heart Leave a comment

#AHA17 highlight: cardiac pacemaker cells

At the American Heart Association Scientific Sessions meeting this week, Hee Cheol Cho’s lab is presenting three abstracts on pacemaker cells. These cells make up the sinoatrial node, which generates electrical impulses driving our heart beats. Knowing how to engineer them could enhance cardiologists’ ability to treat arrhythmias, especially in pediatric patients, but that goal is still some distance away.

Just a glimpse of the challenge comes from graduate student Sandra Grijalva’s late breaking oral abstract describing “Induced Pacemaker Spheroids as a Model to Reverse-Engineer the Native Sinoatrial Node”, which was presented yesterday.

Cho has previously published how induced pacemaker cells can be created by introducing the TBX18 gene into rat cardiac muscle cells. In the new research, when a spheroid of induced pacemaker cells was surrounded by a layer of cardiac muscle cells, the IPM cells were able to drive the previously quiescent nearby cells at around 145 beats per minute. [For reference, rats’ hearts beat in living animals at around 300 beats per minute.] Read more

Posted on by Quinn Eastman in Heart Leave a comment

Stem cell/cardiology researcher Hee Cheol Cho joins Emory

Please welcome stem cell/cardiology researcher Hee Cheol Cho to Emory. Starting in September, Cho joined the Wallace H Counter Department of Biomedical Engineering at Georgia Tech and Emory, and Emory-Children’s Pediatric Research Center. He and his team will focus on developing gene-and cell-based therapies for cardiac arrhythmias. Their research will adding to and complement the research of several groups, such as those led by Chunhui Xu, Young-sup Yoon, Mike Davis and W. Robert Taylor.

Cho comes from Cedars-Sinai Medical Center in Los Angeles, where he specialized in understanding cardiac pacemaker cells, a small group of muscle cells in the sinoatrial node of the heart that initiate cardiac contraction. These cells have specialized electrophysiological properties, and much has been learned in the last few years about the genes that control their development.

Cho and colleagues from Cedars-Sinai recently published a paper in Stem Cell Reports describing how the gene SHOX2 can nudge embryonic stem cells into becoming cardiac pacemaker cells. Read more

Posted on by Quinn Eastman in Heart Leave a comment