Project

Microglia are the brain resident immune cells, which provide the inflammatory response to brain insults. The alpha7 nicotine acetylcholine receptor (a7-nAChR) provides an anti-inflammatory tone in microglia. In recent human evolution, the gene coding for a7-nAChR has been partially duplicated and fused with two other genes ULK4 and GOLGA8B, hereby forming a new fusion gene CHRFAM7A. The gene product of CHRFAM7A, dupa7, codes for a nAChR subunit and can replace one to three a7 subunits in the a7-nAChR, hereby forming a new heteromeric dupa7-a7 nAChR. Dupa7 is a truncated subunit and may negatively modulate a7-nAChR mediated functions, including the anti-inflammatory tone provided in microglia. The effect of CHRFAM7A expression in microglia remains largely unexplored. We aim to further understand if and how CHRFAM7A alters the inflammatory response of microglia. We are using a human induced pluripotent cell (hiPSC) line which has zero copies of the CHRFAM7A gene, in which we overexpressed CHRFAM7A using a lentivirus containing the CHRFAM7A and TdTomato (TdT) construct. As a control we transduced the hiPSC with a lentivirus only containing the TdT construct. From these transduced hiPSC we created hiPSC clones, to ensure an equal amount of lentiviral expression between cells. The hiPSC are differentiated into microglia using an established protocol published by McQuade et al in 2018. To introduce an inflammatory stimulus, the hiPSC derived microglia will be stimulated with lipopolysaccharide (LPS). For this project, bulk RNA sequencing will be used to compare the transcriptomic profiles between microglia expressing or not CHRFAM7A, under basal and inflammatory conditions. This should provide further insight into role of CHRFAM7A expression in the inflammatory response of human microglia. Understanding the human specific inflammatory response is potentially relevant for inflammation associated diseases such as Alzheimer’s Disease.