The properties of hematopoietic stem and progenitor cells (HSPCs), including self-renewal and pluripotency, have been extensively studied. These features have been explored in the management of several haematological disorders and malignancies. Although their role as precursors of innate immune cells is well understood, little is known about their direct participation in host immune response. In this review, we explicate the direct role of HSPCs in the host immune response and highlight therapeutic options for the infectious disease burden that is currently ravaging the world, including COVID-19.
Stem cell therapy is widely used for the treatment of disorders of the blood and immune system but there is comparatively less research devoted to its efficacy in infectious diseases. Although several antibiotics and antivirals have been discovered for the treatment of infectious diseases, a new challenge is posed to the researchers due to the emergence of multiple drug resistance in infectious agents. Infectious agents like SARS COV-2, Mtb (Mycobacterium tuberculosis), HIV and Hepatitis can cause severe tissue and organ damage which can be irreparable. Stem cells, owing to their ability to pervade into the injured region, regenerate and modulate the immune function, can be used as a method to reverse this damage. With the dramatic increase in the number of cases caused by the COVID-19 pandemic, it has become crucial to manage the most severe symptoms such as Acute Respiratory Distress Syndrome (ARDS) and sepsis which have shown promising improvement with the administration of Mesenchymal Stem cells (MSCs) in ongoing clinical trials. This review discusses the scope of stem cell therapy to control some of the most fatal symptoms observed in various infectious diseases. © 2021 Nova Science Publishers, Inc.
Background and objectives: Drug delivery by nebulization has become a crucial strategy for treating different respiratory and lung diseases. Emerging evidence implicates stem cell therapy as a promising tool in treating such conditions, not only by alleviatingthe related symptoms but by improving the prognosis. However, delivery of human peripheral blood-derived stem cells (hPBSCs) to the respiratory airways remains an innovative approach yet to be realized. This study is an analytic, translational, and in vitro research to assess the viability and morphological changes of identified cell populations in hPBSCs cocktail derived from COVID-19 patients. Methods and results: Peripheral blood (PB) samples were obtained from patients enrolled in the SENTAD-COVID Study (ClinicalTrials.gov Reference: NCT04473170). hPBSCs cocktails (n=15) were provided by the Cells Processing Laboratory of Abu Dhabi Stem Cells Center, and were nebulized by three different methods of nebulization: compressor (jet), ultrasonic, and mesh. Our results reported that nucleated CD45(dim) cell count was significantly lower after the three nebulization methods, but nucleated CD45 - cells show a significant decrease only after mesh nebulization. Mesh-nebulized samples had a significant reduction in viability of both CD45(dim) and CD45 cells. Conclusions: This study provides evidence that stem cells derived from PB of COVID-19 patients can be nebulized without substantial loss of cell viability, cell count, and morphological changes using the compressor nebulization. Therefore, we recommend compressor nebulizers as the preferable procedure for hPBSCs delivery to the respiratory airways in further clinical settings.
Most epithelium tissues continuously undergo self-renewal through proliferation and differentiation of epithelial stem cells (known as homeostasis), within a specialized stem cell niche. In highly innervated epithelium, peripheral nerves compose perineural niche and support stem cell homeostasis by releasing a variety of neurotransmitters, hormones, and growth factors and supplying trophic factors to the stem cells. Emerging evidence has shown that both sensory and motor nerves can regulate the fate of epithelial stem cells, thus influencing epithelium homeostasis. Understanding the mechanism of crosstalk between epithelial stem cells and neurons will reveal the important role of the perineural niche in physiological and pathological conditions. Herein, we review recent discoveries of the perineural niche in epithelium mainly in tissue homeostasis, with a limited touch in wound repair and pathogenesis.
