Biology subjects

Mirsaeidi, M.

Publications and source records attributed to Mirsaeidi, M..

3 recordsLinked to original sources

bioRxiv2020

Novel Three-Dimensional Organoid Sarcoidosis Granuloma Model

Sarcoidosis is a multi-system disorder of granulomatous inflammation which most commonly affects the lungs. Its etiology and pathogenesis are not well defined in part due to the lack of reliable modeling. This article presents the development of a novel in vitro three-dimensional lung-on-chip organoid designed to mimic granuloma formation. A lung on chip fluidic macrodevice with three channels for cell culture insertion was developed and added to the previously developed a lung-on-membrane model. Granulomas were cultured from blood samples of patients with sarcoidosis and then inserted in the air-lung-interface (ALI) of the microchip to create a three-dimensional organoid sarcoidosis model (OSGM). The model was tested for cell viability with fibroblasts. We measured the cytokine profiles in medium of OSGM and compared with lung model without granuloma. Concentration of IL-1beta, Il-6, GM-CSF, and IFN-gamma were found significantly higher in OSGM group. The current model represents the first 3D OSGM created by adding a microfluidics system to a dual-chambered lung on membrane model and introducing developed sarcoid-granuloma to its ALI.

immunology↗

bioRxiv2020

Mutation in position of 32 (G>U) of S2M differentiate human SARS-CoV2 from Bat Coronavirus

The new Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) is a zoonotic pathogen that has rapidly mutated and become transmissible to humans. There is little existing data on the mutations in SARS-CoV-2 and the impact of these polymorphisms on its transmission and viral load. In this study, the SARS-CoV-2 genomic sequence was analyzed to identify variants within the 3UTR region of its cis-regulatory RNA elements. A 43-nucleotide genetic element with a highly conserved stem-loop II-like motif (S2M), was discovered. The research revealed 32 G>U and 16 G>U/A mutations located within the S2M sequence in human SARS-CoV-2 models. These polymorphisms appear to make the S2M secondary and tertiary structures in human SARS-CoV-2 models less stable when compared to the S2M structures of bat/pangolin models. This grants the RNA structures more flexibility, which could be one of its escape mechanisms from host defenses or facilitate its entry into host proteins and enzymes. While this S2M sequence may not be omnipresent across all human SARS-CoV-2 models, when present, its sequence is always highly conserved. It may be used as a potential target for the development of vaccines and therapeutic agents.

microbiology↗

bioRxiv2020

Activity of the GHRH Antagonist MIA602 and its Underlying Mechanisms of Action in sarcoidosis

Growth hormone releasing hormone (GHRH) is a potent stimulator of GH secretion from the pituitary gland. Although GHRH is essential for the growth of immune cells, the regulatory effects of its antagonist in granulomatous disease remains unknown. Here, we report expression of GHRH receptor (R) in human tissue with sarcoidosis granuloma and demonstrate the anti-inflammatory effects of MIA602 (a GHRH antagonist) in two in vitro human granuloma models and an in vivo granuloma model. MIA602 decreases levels of IL2, IL12, and IL17A in in vitro granuloma model. We show further that the anti-inflammatory effect of MIA602 appears to be mediated by reduction in CD45++CD68+ cells in granulomatous tissue and upregulation in PD-1 expression in macrophages. In analysis of expression of proteins involved in the mitochondrial stage of apoptosis, we show that MIA602 increases the levels of caspase 3, BCL-xL/BAK dimer, and MCl-1/Bak dimer in granuloma. These findings indicate that MIA602 may not induce apoptosis. The clinical relevance of our findings further suggest that HGRH-R is potentially a target for treatment of granulomatous disease and MIA602 possibly a novel therapeutic agent for sarcoidosis.

immunology↗