ABSTRACT
OBJECTIVE: This study aimed to present the case of a boy with acute distress syndrome (ARDS) treated with low-dose umbilical cord blood (UCB) therapy and explore the underlying possible mechanism. METHODS: A 7-year-old boy with severe Pneumocystis carinii pneumonia and severe ARDS was treated with allogeneic UCB as salvage therapy. RESULTS: The patient did not improve after being treated with lung protective ventilation, pulmonary surfactant replacement, and extracorporeal membrane oxygenation (ECMO) for 30 days. However, his disease reversed 5 days after allogeneic UCB infusion, and he weaned from ECMO after 7 days of infusion. Bioinformatics confirmed that his Toll-like receptor (TLR) was abnormal before UCB infusion. However, after the infusion, his immune system was activated and repaired, and the TLR4/MyD88/NF-κB signaling pathway was recovered. CONCLUSION: Allogenic UCB could treat ARDS by repairing the TLR4/MyD88/NF-κB signaling pathway, thereby achieving stability of the immune system.
Subject(s)
Cord Blood Stem Cell Transplantation/methods , Extracorporeal Membrane Oxygenation/methods , Fetal Blood/cytology , Pneumocystis carinii/isolation & purification , Pneumonia, Pneumocystis/complications , Respiratory Distress Syndrome/therapy , Child , Humans , Male , Pneumonia, Pneumocystis/microbiology , Prognosis , Respiration, Artificial , Respiratory Distress Syndrome/microbiology , Transplantation, HomologousABSTRACT
Thymalin is a polypeptide complex isolated from the thymus and regulating the functions of the immune system. Thymalin is effective in therapy of acute respiratory syndrome, chronic obstructive bronchitis, and other immunopathology. Thymalin increases functional activity of T lymphocytes, but the targeted molecular mechanism of its biological activity requires further study. We studied the influence of thymalin on differentiation of human hematopoietic stem cells (HSC) and expression of CD28 molecule involved in the implementation of antiviral immunity in COVID-19 infection. It was found that thymalin reduced the expression of CD44 (stem cell marker) and CD117 (molecule of the intermediate stage of HSC differentiation) by 2-3 times and increased the expression of CD28 (marker of mature T lymphocytes) by 6.8 times. This indirectly indicates that thymalin stimulated differentiation of CD117+ cells into mature CD28+T lymphocytes. It is known that in patients with severe COVID-19, the number of CD28+, CD4+, CD8+T lymphocytes in the blood decreased, which attested to a pronounced suppression of immunity. It is possible that the antiviral effect of thymalin consists in compensatory stimulation of HSC differentiation into CD28+T lymphocytes at the stage of immunity suppression in unfavorable course of viral infection. Thymalin can be considered as an immunoprotective peptide drug for the prevention of COVID-19.
Subject(s)
Cell Differentiation/drug effects , Hematopoietic Stem Cells/drug effects , Hematopoietic Stem Cells/physiology , Thymus Hormones/pharmacology , CD28 Antigens/genetics , CD28 Antigens/metabolism , COVID-19/immunology , COVID-19/pathology , Cell Differentiation/genetics , Cells, Cultured , Fetal Blood/cytology , Gene Expression Regulation/drug effects , Hematopoietic Stem Cells/pathology , Humans , Hyaluronan Receptors/genetics , Hyaluronan Receptors/metabolism , Proto-Oncogene Proteins c-kit/genetics , Proto-Oncogene Proteins c-kit/metabolism , SARS-CoV-2/immunology , T-Lymphocytes/drug effects , T-Lymphocytes/metabolism , T-Lymphocytes/physiology , Thymus Hormones/physiologyABSTRACT
INTRODUCTION: The coronavirus disease 2019 (COVID-19) pandemic is spreading rapidly. Critically ill cases of COVID-19 can rapidly progress to acute respiratory distress syndrome and multiple organ failures. However, no effective drugs have been available till now, leading to more than 300,000 deaths up to 29 April 2020. Here, we present a critically ill case utilizing umbilical cord blood-derived mesenchymal stem cells (UCB-MSCs). CASE PRESENTATION: A 72-year-old man was admitted, with the diagnosis of COVID-19, ARDS, type-2 diabetes, diabetic nephropathy, renal insufficiency, and hypertension. His clinical condition continually developed to be life-threatening even receiving various treatment options including antiviral therapy and extracorporeal membrane oxygenation. Between 28 February and 8 March 2020, the patient was given 5-time intravenous infusions of UCB-MSCs. His hematological and biochemical indexes, including lymphocytes and renal function improved. Pulmonary static compliance increased significantly and PaO2/FiO2 ratio maintained stable. On March 10, he received lung transplantation. CONCLUSIONS: Our current findings suggested that UCB-MSCs therapy may show some positive effect in treating critical COVID-19 to some extent, for its delaying deterioration of the disease and efficacy in respiratory and renal function, though limited.