A variety of cells can be applied as vectors for the targeted delivery of chemotherapeutic or gene therapeutic agents to neoplasms. Macrophages are regarded as promising candidates for cell-based therapy. Accurate assessments of the efficacy and safety profiles of cell-based therapy products require the collection of data on their biodistribution and fate. The study of living cell distribution in vivo necessitates the utilization of a combination of methodologies to obtain more precise data regarding the fate of cells after their administration into animals. In the present study, a murine RAW 264.7 cell line was engineered to express enhanced green fluorescent protein (GFP). These cells were labeled with 50 nm magnetic nanoparticles (MNPs) for non-invasive real-time monitoring in mice using the magnetic particle quantification (MPQ) technique. The combination of high sensitivity and multimodality of the approach used permitted the acquisition of comprehensive data on the biodistribution of RAW-GFP cells in mice. For the first time, non-invasive, real-time monitoring of the dynamics of MNP-loaded macrophages in the bloodstream of mice has been achieved via the MPQ technique. Following intravenous administration, the cells are rapidly eliminated from the bloodstream, with subsequent accumulation mainly in the lungs and the liver. This may impose limitations on the use of such cells for drug delivery to other regions of a living organism.

Induced pluripotent stem cells (iPSCs) can be generated from various adult cells, genetically modified and differentiated into diverse cell populations. Type I interferons (IFN-Is) have multiple immunotherapeutic applications; however, their systemic administration can lead to severe adverse outcomes. One way of overcoming the limitation is to introduce cells able to enter the site of pathology and to produce IFN-Is locally. As a first step towards the generation of such cells, here, we aimed to generate human iPSCs overexpressing interferon-beta (IFNB, IFNB-iPSCs). IFNB-iPSCs were obtained by CRISPR/Cas9 editing of the previously generated iPSC line K7-4Lf. IFNB-iPSCs overexpressed IFNB RNA and produced a functionally active IFN-β. The cells displayed typical iPSC morphology and expressed pluripotency markers. Following spontaneous differentiation, IFNB-iPSCs formed embryoid bodies and upregulated endoderm, mesoderm, and some ectoderm markers. However, an upregulation of key neuroectoderm markers, PAX6 and LHX2, was compromised. A negative effect of IFN-β on iPSC neuroectoderm differentiation was confirmed in parental iPSCs differentiated in the presence of a recombinant IFN-β. The study describes new IFN-β-producing iPSC lines suitable for the generation of various types of IFN-β-producing cells for future experimental and clinical applications, and it unravels an inhibitory effect of IFN-β on stem cell neuroectoderm differentiation.

Type 1 interferons (IFN-Is) exhibit significant antiviral, antitumor, and immunoregulatory properties, demonstrating substantial therapeutic potential. However, IFN-Is are pleiotropic cytokines, and the available data on their effect under specific pathological conditions are inconclusive. Furthermore, the systemic administration of IFN-Is can result in side effects. Generating cells that can migrate to the pathological focus and provide regulated local production of IFN-Is could overcome this limitation and provide a model for an in-depth analysis of the biological and therapeutic effects of IFN-Is. Induced pluripotent stem cells (iPSCs) are a valuable source of various differentiated cell types, including human immune cells. In this study, we describe the generation of genetically modified human iPSCs with doxycycline-controlled overexpression of interferon β (IFNB1). Three IFNB1-overexpressing iPSC lines (IFNB-iPSCs) and one control line expressing the transactivator M2rtTA (TA-iPSCs) were generated using the CRISPR/Cas9 technology. The pluripotency of the generated cell lines has been confirmed by the following: (i) cell morphology; (ii) the expression of the pluripotency markers OCT4, SOX2, TRA 1-60, and NANOG; and (iii) the ability to spontaneously differentiate into the derivatives of the three germ layers. Upon the addition of doxycycline, all IFNB-iPSCs upregulated IFNB1 expression at RNA (depending on the iPSC line, 126-816-fold) and protein levels. The IFNB-iPSCs and TA-iPSCs generated here represent a valuable cellular model for studying the effects of IFN-β on the activity and differentiation trajectories of different cell types, as well as for generating different types of cells with controllable IFN-β expression.