RESUMO
The coronavirus disease 2019 (COVID-19) outbreak is an ongoing global health emergence, but the pathogenesis remains unclear. We revealed blood cell immune response profiles using 5 mRNA, TCR and BCR V(D)J transcriptome analysis with single-cell resolution. Data from 134,620 PBMCs and 83,387 TCR and 12,601 BCR clones was obtained, and 56 blood cell subtypes and 23 new cell marker genes were identified from 16 participants. The number of specific subtypes of immune cells changed significantly when compared patients with controls. Activation of the interferon-MAPK pathway is the major defense mechanism, but MAPK transcription signaling is inhibited in cured patients. TCR and BCR V(D)J recombination is highly diverse in generating different antibodies against SARS-CoV-2. Therefore, the interferon-MAPK pathway and TCR-and BCR-produced antibodies play important roles in the COVID-19 immune response. Immune deficiency or immune over-response may result in the condition of patients with COVID-19 becoming critical or severe.
RESUMO
BACKGROUND: Evidence exists that inhibition of matrix metanoproteinase-2(MMP-2) secretion in the proliferating hernangioma tissue by transfection of adenovirus-active MMP-2(Ad-aMMP-2) cDNA would become an important means for treatment of proliferating hemangioma.OBJECTIVE: To investigate the influences of Ad-aMMP-2 cDNA transfection on human proliferating hemangioma growth in nude mice.DESIGN, TIME AND SETTING: A randomized, grouping, and controlled observation was performed in West China Hospital of Sichuan University between August 2003 and September 2004.MATERIALS: Eighteen BALB/c-nu/nu nude mice, weighing approximately 20 g, were included. Cavernous hemangioma specimen pathologically confirmed as proliferating hemangioma was resected from one 52-day-old female child patient.METHODS: The freshly reseoted human proliferating hemangioma specimen was sliced into small pieces with a size of 5 mm×4 mm×3 mm and subcutaneously implanted into the back of 18 nude mice within 1 hour to develop mouse models of hemangioma.Forty-five days after hemangioma implantation, 15 successful hemangioma nude mice were treated by intratumoral administration of adenovirus green fluorescent protein (Ad-GFP1 n = 51 Ad-GFP group), adenovirus-active MMP-2 (n = 5, Ad-aMMP-2 group), or the same amount of phosphate buffered saline (PBS1 n = 51 control group). Intratumoral administration was performed once every other day, for a total of 4 times.MAIN OUTCOME MEASURES: Observation of tumor volume and compadson of tumor necrosis area among 3 groups; detection of GFP expression in nude mouse; gross, hematoxylin-eosin staining, and transmission etectron microscope observation of tumor tissue morphology; determination of MMP-2 cDNA expression and microvascular density by immunohistochemistry; and detection of growth cycle and apoptosis of tumor cells by flow cytometry.RESULTS:①Ad-aMMP-2 could inhibit hemangioma growth in vivo, without marked adverse reactions. Tumor necrosis of different degrees was found in each group, and tumor necrosis area was significantly greater in the Ad-aMMP-2 group than in the control and Ad-GFP groups (P < 0.01). ②Histological sections displayed GFP gene expression in the Ad-GFP group. ③Gross observation results revealed relatively large tumor tissue in the control and Ad-GFP groups and relatively small tumor tissue in the Ad-aMMP-2 group. Hernatoxylin-eosin staining results showed that in the control and Ad-GFP groups, endothelial cells aggregated together in strip-shaped or lump-shaped appearance, and in the Ad-aMMP-2 group, there were many necrotic loci arranging in lamellar-shape appearance. Transmission electron microscope results revealed vascular endothelial cells with normal morphology in the control group and tumor cells with apparent nucleoli in the Ad-GFP group, while in the Ad-aMMP-2 group, some vascular endothelial cells exhibited chromatin pycnosis in the nucleus, forming apoptotic bodies.④ MMP-2 expression and microvascular density were significantly reduced in the Ad-aMMP-2 group than in the Ad-GFP and control groups (P < 0.05). ⑤The percentage of tumor cells in G0/G1 phase was significantly higher (P < 0.05), while the proliferating index was significantly decreased, in the Ad-aMMP-2 group than in the Ad-GFP and control groups. The Ad-aMMP-2 group exhibited higher apoptosis rate of tumor cells (P < 0.05), as well as more markedly increasing apoptosis index, than the control and Ad-GFP groups.CONCLUSION: It is feasible to block human proliferating hemangioma growth by transfeotion of Ad-aMMP-2 cDNA. The included mechanisms are to inhibit vascular endothelial cells to secrete MMP-21 thereby leading to local ischemia.
