Unraveling the Inflammatory Response to Cardiopulmonary Bypass – Genetic Analysis

By Luc Puis

Every perfusionist knows that the use of cardiopulmonary bypass (CPB) is often blamed for initiating an inflammatory reaction that can cause complications in the postoperative period. Many measures like coating, miniaturizing the circuit, drugs, and biocompatible materials are being used to mitigate this reaction. 

As inflammation is the body’s defense mechanism, we might face a limit to what is possible to prevent this from happening. Even if we could avoid CPB, a sternotomy and the consequent cauterization of the sternum is quite inflammatory on its own. 

Researchers in China thought that if we can’t avoid this inflammatory response, what can we do to make it less harmful? They looked at the genes expressed when patients submitted to CPB. The genetic information was collected from 20 pediatric patients, either for Tetralogy of Fallot or for an atrial septal defect, and bioinformatics was used to analyze the datasets. This is only possible thanks to artificial intelligence, powerful computers, and the international sharing of information.

Genetic sets (genes) responsible for inflammation were investigated and determined that 4 top genes (JUN,  FOS,  ATF3,  and  EGR1  for the fanatics) are potentially involved in inflammation and various complications after CPB. Also, the AP-1 pathway (a transcription factor that regulates gene expression in response to multiple stimuli, including cytokines, growth factors, stress, and bacterial and viral infections, red.) may play an essential role in the occurrence of ischemia-reperfusion injury and systemic inflammation caused by CPB.

One limitation of this study is that the expression of the genes was not associated with the level of inflammation that did or did not happen in the children. But this was the first step in finding therapies to mitigate the effects of CPB on the inflammatory response.

So, whenever someone tries to blame you for exacerbating a patient’s inflammatory response, you will soon be able to say: it’s all in the genes…

Sources

Qi Q et al. Bioinformatics Analysis Reveals Hub Genes That May Reduce Inflammation and Complications After Cardiopulmonary Bypass. The Heart Surgery Forum, 25(2), E243-E252

AP-1 transcription factor. (2022, June 21). In Wikipedia. https://en.wikipedia.org/wiki/AP-1_transcription_factor (last accessed 09/07/2022)