Rare genetic disor­ders lead to a failure to produce enough blood cells that are frequently fatal, seen most often among young children. These diseases are primar­ily monogenic, caused by the loss of function in a single gene. To inves­ti­gate the effects of this loss of function, my project seeks to mimic it outside of the human body, specif­i­cally in human bone marrow organoids (BMOs). By study­ing BMOs, the aim is to identify criti­cal factors contribut­ing to bone marrow failure and ultimately use this infor­ma­tion to develop new diagnos­tic methods.

All blood cells origi­nate from hematopoi­etic stem cells (HSCs) in the bone marrow, a process known as hematopoiesis. HSCs can differ­en­ti­ate into both myeloid and lymphoid cells, giving rise to all blood cell types, and can undergo self-renewal and differ­en­ti­a­tion to increase their numbers. Hematopoiesis is a hierar­chi­cal and highly regulated process, and many genetic diseases are a result of dysfunc­tion in this regula­tion, broadly termed bone marrow failure. However, study­ing these diseases has been challeng­ing due to the limited avail­abil­ity of human bone marrow samples. Dysfunc­tion in the bone marrow has proven diffi­cult to study in animal models.  Using human bone marrow organoids grown from iPSCs will allow these errors to be modeled in a human setting. 

Severe congen­i­tal neutrope­nia (SCN) is a genetic disor­der affect­ing hematopoiesis, with multi­ple genes contribut­ing to or causing the disease. Deficien­cies in VPS45, SMARCD2, HAX1, and ELANE lead to congen­i­tal neutrope­nia. By using CRISPR-Cas9 to intro­duce loss-of-function mutations in these genes, we can inves­ti­gate whether bone marrow organoids can mimic the pheno­type of these errors. I will deter­mine if they can be used to inves­ti­gate aberra­tions like fibro­sis in these errors, by inhibit­ing defined pro-fibrino­genic pathways, aiming to eluci­date the criti­cal factors that lead to bone marrow dysfunc­tion.  Finally, I will estab­lish how to trans­late this multi-omics single-cell-based analy­sis into cutting-edge diagnos­tics. My Ph.D. project aims to corre­late morpho­log­i­cal data on primary bone marrow smears and bone marrow organoids (BMOs) with genomic and transcrip­tomic datasets.