PhD Scientific Days 2026

Poster Session 3.U - Molecular Medicine

CRISPR-Engineered HoxB8 Cells for the Analysis of PKC Isoforms in Neutrophil Antibacterial Responses

Name of the presenter

Görög, Daniella

Institute/workplace of the presenter

Semmelweis University

Authors

Daniella Görög¹, Emiliána Jex¹, Áron Pánczél¹, Attila Mócsai¹
1: Department of Physiology, Semmelweis University, Budapest, Hungary

Text of the abstract

In conditionally immortalized HoxB8 progenitors, the estrogen-dependent HoxB8 transcription factor maintains the cells in a myeloid progenitor stage. Upon estrogen withdrawal, HoxB8 progenitors differentiate into neutrophil-like cells (HoxB8 NLCs), offering a suitable framework for genetic modification and functional analysis of the neutrophil lineage.
These progenitors were subjected to targeted CRISPR/Cas9 gene editing to disrupt the genes encoding the nine known PKC isoforms (Prkc CRKOs).

Phagocytosis of normal murine serum-opsonized or non-opsonized GFP-expressing Staphylococcus aureus was followed by flow cytometry. Bacterial survival was tested using the AlamarBlue cell viability assay or by quantifying colony-forming units. Spreading was tested by stimulating cells with TNFα or Pam3CSK4 on a fibrinogen surface, or by plating cells on immobilized IgG immune complexes without additional stimulus. Cell shape changes are assessed by phase contrast microscopy. 2D chemotactic migration of HoxB8 NLCs was tested in fibrinogen-coated IBIDI µ-slide Chemotaxis chambers towards an fMLP gradient by analyzing single-cell trajectories.

Wild type (Empty Vector transduced, EV) HoxB8 NLCs were able to spread over the fibrinogen surfaces, or over an immobilized IgG immune complex surface. EV NLCs were able to effectively migrate towards fMLP gradient and were able to show antibacterial functions against Staphylococcus aureus bacteria of the USA300 strain. Disrupting a single Prkc isoform-encoding gene did not affect neutrophil spreading on fibrinogen surfaces upon TNFα or Pam3CSK4 stimulation. Prkcd CRKO cells showed partially reduced spreading ability on immune complex surfaces. Disruption of a single Prkc gene is insufficient to completely abolish antibacterial functions.