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1.
BMC Vet Res ; 19(1): 26, 2023 Jan 30.
Article in English | MEDLINE | ID: covidwho-2287307

ABSTRACT

BACKGROUND: Porcine circovirus type 2 (PCV2) is one of the major pathogens commonly found in pigs, which causes immunosuppression and apoptosis. Vaccination and a single drug cannot totally prevent and treat PCV2 infection. Our previous in vitro study reported that the synergistic anti-PCV2 effect of Matrine and Osthole was better than that of Matrine or Osthole alone, This study was aimed to evaluate the synergistic anti-PCV2 effect as well as the underline molecular mechanism of Matrine and Osthole in Kunming (KM) mice model infected with PCV2. KM mice were randomly divided into 8 groups namely control group, PCV2 infected, Matrine combined with Osthole high dose treatment (40 mg/kg + 12 mg/kg), medium dose treatment (20 mg/kg + 6 mg/kg), low dose treatment (10 mg/kg + 3 mg/kg), Matrine treatment (40 mg/kg), Osthole treatment (12 mg/kg) and Ribavirin positive control (40 mg/kg) groups. PCV2 was intraperitoneally (i.p.) injected in all mice except the control group. 5 days of post-infection (dpi), mice in different treatment groups were injected i.p. with various doses of Matrine, Osthole and Ribavirin once daily for the next 5 consecutive days. RESULTS: The synergistic inhibitory effect of Matrine and Osthole on PCV2 replication in mouse liver was significantly heigher than that of Matrine and Osthole alone. The expression of GRP78, p-PERK, p-eIF2α, ATF4, CHOP, cleaved caspase-3 and Bax proteins were significantly reduced, while that of Bcl-2 was significantly increased in Matrine combined with Osthole groups, which alleviated the pathological changes caused by PCV2, such as interstitial pneumonia, loss of spleen lymphocytes, infiltration of macrophages and eosinophils. CONCLUSIONS: The synergistic anti-apoptotic effect of Matrine and Osthole was better than their alone effect, Both Matrine and Osthole had directly inhibited the expression of PCV2 Cap and the apoptosis of spleen cells induced by PCV2 Cap through the PERK pathway activated by endoplasmic reticulum (ER) GRP78. These results provided a new insight to control PCV2 infection and provide good component prescription candidate for the development of novel anti-PCV2 drugs.


Subject(s)
Circoviridae Infections , Circovirus , Matrines , Animals , Mice , Apoptosis , Circoviridae Infections/drug therapy , Circoviridae Infections/pathology , Endoplasmic Reticulum Chaperone BiP , Matrines/pharmacology , Ribavirin/pharmacology , Spleen
2.
Rev Assoc Med Bras (1992) ; 68(6): 751-753, 2022.
Article in English | MEDLINE | ID: covidwho-2234373

Subject(s)
COVID-19 , Spleen , Humans , Liver , Recurrence
3.
Front Immunol ; 13: 889876, 2022.
Article in English | MEDLINE | ID: covidwho-2198816

ABSTRACT

IgM memory B cells, are a peculiar subset of memory B cells, which probably originates in the spleen and outside germinal centers and provide a rapid line of defence against mucosal infections. Their role in counteracting COVID-19 is still elusive but, recent evidence, mainly boosted by studies on spleen function/involvement in COVID-19, seems to support the notion that this subset of memory B cells could exert a protective role against this virus, along with other coronaviruses, particularly in the acute setting of the infection, as outlined by worst clinical outcomes observed in unvaccinated patients with impaired IgM B memory response and spleen function. Herein we critically summarise the current landscape of studies on IgM memory B cells, focusing on the clinical impact of their depletion, by comparing the COVID-19-related splenic dysfunction with other hypo- and asplenic conditions and by adding recent data on follow-up studies and postulate a mechanistic explanation for their reduced numbers. The early detection of an impaired IgM memory B cell response in patients with COVID-19 may contribute to their improved care through different strategies, such as through tailored vaccine strategies, prompt hospital admission and/or administration of anti-infective treatments, thus resulting in an better prognosis, although at present management algorithms are still unavailable. Moreover, further studies with longer follow-up are needed to assess the evolution of COVID-19-associated/exacerbated immune deficit.


Subject(s)
COVID-19 , Humans , Immunoglobulin M , Immunologic Memory , Memory B Cells , Spleen
4.
Vaccine ; 40(37): 5494-5503, 2022 09 02.
Article in English | MEDLINE | ID: covidwho-2016161

ABSTRACT

In recent years, several advances have been observed in vaccinology especially for neglected tropical diseases (NTDs). One of the tools employed is epitope prediction by immunoinformatic approaches that reduce the time and cost to develop a vaccine. In this scenario, immunoinformatics is being more often used to develop vaccines for NTDs, in particular visceral leishmaniasis (VL) which is proven not to have an effective vaccine yet. Based on that, in a previous study, two predicted T-cell multi-epitope chimera vaccines were experimentally validated in BALB/c mice to evaluate the immunogenicity, central and effector memory and protection against VL. Considering the results obtained in the mouse model, we assessed the immune response of these chimeras inMesocricetus auratushamster, which displays, experimentally, similar pathological status to human and dog VL disease. Our findings indicate that both chimeras lead to a dominant Th1 response profile, inducing a strong cellular response by increasing the production of IFN-γ and TNF-α cytokines associated with a decrease in IL-10. Also, the chimeras reduced the spleen parasite load and the weight a correlation between protector immunological mechanisms and consistent reduction of the parasitic load was observed. Our results demonstrate that both chimeras were immunogenic and corroborate with findings in the mouse model. Therefore, we reinforce the use of the hamster as a pre-clinical model in vaccination trials for canine and human VL and the importance of immunoinformatic to identify epitopes to design vaccines for this important neglected disease.


Subject(s)
Leishmania infantum , Leishmaniasis Vaccines , Leishmaniasis, Visceral , Th1 Cells , Animals , Cricetinae , Dogs , Humans , Mice , Adjuvants, Immunologic , Antigens, Protozoan , Cytokines , Dog Diseases , Epitopes, T-Lymphocyte , Leishmaniasis, Visceral/prevention & control , Mice, Inbred BALB C , Spleen
5.
Blood ; 140(5): 478-490, 2022 08 04.
Article in English | MEDLINE | ID: covidwho-1974106

ABSTRACT

Vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are based on a range of novel platforms, with adenovirus-based approaches (like ChAdOx1 nCov-19) being one of them. Recently, a novel complication of SARS-CoV-2-targeted adenovirus vaccines has emerged: immune thrombocytopenia, either isolated, or accompanied by thrombosis (then termed VITT). This complication is characterized by low platelet counts, and in the case of VITT, also by platelet-activating platelet factor 4 antibodies reminiscent of heparin-induced thrombocytopenia, leading to a prothrombotic state with clot formation at unusual anatomic sites. Here, we detected antiplatelet antibodies targeting platelet glycoprotein receptors in 30% of patients with proven VITT (n = 27) and 42% of patients with isolated thrombocytopenia after ChAdOx1 nCov-19 vaccination (n = 26), indicating broad antiplatelet autoimmunity in these clinical entities. We use in vitro and in vivo models to characterize possible mechanisms of these platelet-targeted autoimmune responses leading to thrombocytopenia. We show that IV but not intramuscular injection of ChAdOx1 nCov-19 triggers platelet-adenovirus aggregate formation and platelet activation in mice. After IV injection, these aggregates are phagocytosed by macrophages in the spleen, and platelet remnants are found in the marginal zone and follicles. This is followed by a pronounced B-cell response with the emergence of circulating antibodies binding to platelets. Our work contributes to the understanding of platelet-associated complications after ChAdOx1 nCov-19 administration and highlights accidental IV injection as a potential mechanism of platelet-targeted autoimmunity. Hence, preventing IV injection when administering adenovirus-based vaccines could be a potential measure against platelet-associated pathologies after vaccination.


Subject(s)
COVID-19 Vaccines , COVID-19 , ChAdOx1 nCoV-19 , Thrombocytopenia , Animals , COVID-19/prevention & control , COVID-19 Vaccines/adverse effects , ChAdOx1 nCoV-19/adverse effects , Immunity , Mice , Platelet Factor 4 , SARS-CoV-2 , Spleen , Thrombocytopenia/etiology
6.
Mol Ther ; 30(9): 3078-3094, 2022 09 07.
Article in English | MEDLINE | ID: covidwho-1926985

ABSTRACT

mRNA vaccines have recently proved to be highly effective against SARS-CoV-2. Key to their success is the lipid-based nanoparticle (LNP), which enables efficient mRNA expression and endows the vaccine with adjuvant properties that drive potent antibody responses. Effective cancer vaccines require long-lived, qualitative CD8 T cell responses instead of antibody responses. Systemic vaccination appears to be the most effective route, but necessitates adaptation of LNP composition to deliver mRNA to antigen-presenting cells. Using a design-of-experiments methodology, we tailored mRNA-LNP compositions to achieve high-magnitude tumor-specific CD8 T cell responses within a single round of optimization. Optimized LNP compositions resulted in enhanced mRNA uptake by multiple splenic immune cell populations. Type I interferon and phagocytes were found to be essential for the T cell response. Surprisingly, we also discovered a yet unidentified role of B cells in stimulating the vaccine-elicited CD8 T cell response. Optimized LNPs displayed a similar, spleen-centered biodistribution profile in non-human primates and did not trigger histopathological changes in liver and spleen, warranting their further assessment in clinical studies. Taken together, our study clarifies the relationship between nanoparticle composition and their T cell stimulatory capacity and provides novel insights into the underlying mechanisms of effective mRNA-LNP-based antitumor immunotherapy.


Subject(s)
COVID-19 , Cancer Vaccines , Nanoparticles , Animals , Immunization/methods , Immunotherapy , RNA, Messenger/metabolism , SARS-CoV-2/genetics , Spleen , Tissue Distribution , Vaccination/methods
7.
Clin Nucl Med ; 47(10): e658-e659, 2022 Oct 01.
Article in English | MEDLINE | ID: covidwho-1874067

ABSTRACT

ABSTRACT: Newly diagnosed low-grade bilateral breast lymphoma in 63-year-old woman demonstrated intense FDG uptake in the left axillary lymph nodes and the spleen, concerning for lymphomatous involvement. Subsequent ultrasound-guided biopsy did not demonstrate any pathologic left axillary lymph nodes. Further investigation revealed COVID-19 vaccination in the left arm, 5 days prior to the 18 F-FDG PET/CT study. Six-month follow-up 18 F-FDG PET/CT showed resolution of the intense FDG uptake in the left axillary lymph nodes and spleen without any treatment, suggesting a self-remitting acute local and systemic immune response to COVID-19 vaccination.


Subject(s)
COVID-19 , Fluorodeoxyglucose F18 , COVID-19 Vaccines , Female , Follow-Up Studies , Humans , Lymph Nodes/diagnostic imaging , Lymph Nodes/pathology , Middle Aged , Positron Emission Tomography Computed Tomography , Spleen/diagnostic imaging , Vaccination
8.
Cell Calcium ; 105: 102605, 2022 07.
Article in English | MEDLINE | ID: covidwho-1850778

ABSTRACT

Gain-of-function mutations on STIM1 and ORAI1 genes are responsible for an increased store-operated calcium entry, and underlie the characteristic symptoms of three overlapping ultra-rare genetic disorders (i.e tubular aggregate myopathy, Stormorken syndrome, York platelet syndrome) that can be grouped as tubular aggregate myopathies. These mutations lead to a wide spectrum of defects, which usually include muscle weakness and cramps. Negative modulators of store-operated Ca2+-entry targeting wild-type STIM1 and ORAI1 have entered clinical trials for a different array of disorders, including pancreatitis, COVID-19, cancer, and autoimmune disorders and, while efficacy data is awaited, safety data indicates tolerability of this STIM1/ORAI1 mutations are amenable to pharmacological intervention. If this were so, given that there are no approved treatments or clinical trials ongoing for these rare disorders, it could be envisaged that these agents could also rehabilitate tubular aggregate myopathy patients. In the present contribution we characterized the Ca2+-entry patterns induced by eleven STIM1 and three ORAI1 mutations in heterologous systems or in patient-derived cells, i.e. fibroblasts and myotubes, and evaluated the effect of CIC-37 and CIC-39, two novel store-operated calcium entry modulators. Our data show that all STIM1 and ORAI1 gain-of-function mutations tested, with the possible exception of the R304Q STIM1 mutation, are amenable to inhibition, albeit with slightly different sensitivities, paving the way to the development of SOCE modulators in tubular aggregate myopathies.


Subject(s)
COVID-19 , Myopathies, Structural, Congenital , Blood Platelet Disorders , Calcium/metabolism , Dyslexia , Erythrocytes, Abnormal , Humans , Ichthyosis , Migraine Disorders , Miosis , Muscle Fatigue , Mutation/genetics , Myopathies, Structural, Congenital/genetics , Neoplasm Proteins/genetics , ORAI1 Protein/genetics , Spleen/abnormalities , Stromal Interaction Molecule 1/genetics
9.
J Virol ; 96(9): e0003822, 2022 05 11.
Article in English | MEDLINE | ID: covidwho-1788914

ABSTRACT

Due to the limitation of human studies with respect to individual difference or the accessibility of fresh tissue samples, how severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection results in pathological complications in lung, the main site of infection, is still incompletely understood. Therefore, physiologically relevant animal models under realistic SARS-CoV-2 infection conditions would be helpful to our understanding of dysregulated inflammation response in lung in the context of targeted therapeutics. Here, we characterized the single-cell landscape in lung and spleen upon SARS-CoV-2 infection in an acute severe disease mouse model that replicates human symptoms, including severe lung pathology and lymphopenia. We showed a reduction of lymphocyte populations and an increase of neutrophils in lung and then demonstrated the key role of neutrophil-mediated lung immunopathology in both mice and humans. Under severe conditions, neutrophils recruited by a chemokine-driven positive feedback produced elevated "fatal signature" proinflammatory genes and pathways related to neutrophil activation or releasing of granular content. In addition, we identified a new Cd177high cluster that is undergoing respiratory burst and Stfahigh cluster cells that may dampen antigen presentation upon infection. We also revealed the devastating effect of overactivated neutrophil by showing the highly enriched neutrophil extracellular traps in lung and a dampened B-cell function in either lung or spleen that may be attributed to arginine consumption by neutrophil. The current study helped our understanding of SARS-CoV-2-induced pneumonia and warranted the concept of neutrophil-targeting therapeutics in COVID-19 treatment. IMPORTANCE We demonstrated the single-cell landscape in lung and spleen upon SARS-CoV-2 infection in an acute severe disease mouse model that replicated human symptoms, including severe lung pathology and lymphopenia. Our comprehensive study revealed the key role of neutrophil-mediated lung immunopathology in SARS-CoV-2-induced severe pneumonia, which not only helped our understanding of COVID-19 but also warranted the concept of neutrophil targeting therapeutics in COVID-19 treatment.


Subject(s)
COVID-19 , Lung , Neutrophils , Animals , COVID-19/immunology , Disease Models, Animal , Humans , Lung/pathology , Lung/virology , Lymphopenia/virology , Mice , Neutrophils/immunology , SARS-CoV-2 , Spleen/pathology , Spleen/virology
10.
J Vet Diagn Invest ; 34(2): 334-338, 2022 Mar.
Article in English | MEDLINE | ID: covidwho-1770120

ABSTRACT

A concurrent outbreak of infection with Yersinia pseudotuberculosis occurred in adult captive African lions (Panthera leo). Two 17-y-old male lions and one 14-y-old female lion developed respiratory distress, lethargy, ataxia, and hyporexia. Within 3-5 d of the onset of clinical signs, one male and the female lion died and were submitted for postmortem examination. Macroscopically, the liver and spleen had multifocal-to-coalescing, semi-firm, pale-tan nodules throughout the parenchyma. The lungs were non-collapsed and marked by petechiae. Histologic examination identified lytic, necrosuppurative foci in the liver, spleen, lungs, and kidney, with abundant intralesional gram-negative coccobacilli in the male lion. Similar findings were seen in the female lion in the liver, spleen, kidney, and mesenteric lymph node; however, the intralesional bacterial colonies were more pleomorphic, comprising rod and filamentous morphologies. Aerobic bacterial culture of the liver, spleen, and lung revealed Y. pseudotuberculosis growth. The source of infection is unknown, and an epidemiologic study was performed. Sources to be considered are from the predation of rodent and/or bird reservoirs, or contaminated soil or water. Mortality associated with Y. pseudotuberculosis has been described in an African lion cub, however, to our knowledge, Y. pseudotuberculosis has not been reported in adult African lions, and this is only the second report of Y. pseudotuberculosis with aberrant bacterial morphology observed histologically.


Subject(s)
Lions , Yersinia pseudotuberculosis Infections , Yersinia pseudotuberculosis , Animals , Disease Outbreaks/veterinary , Female , Male , Spleen/pathology , Yersinia pseudotuberculosis Infections/epidemiology , Yersinia pseudotuberculosis Infections/microbiology , Yersinia pseudotuberculosis Infections/veterinary
11.
Commun Biol ; 5(1): 242, 2022 03 18.
Article in English | MEDLINE | ID: covidwho-1751765

ABSTRACT

Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), the cause of coronavirus disease 2019 (COVID-19), has incited a global health crisis. Currently, there are limited therapeutic options for the prevention and treatment of SARS-CoV-2 infections. We evaluated the antiviral activity of sulforaphane (SFN), the principal biologically active phytochemical derived from glucoraphanin, the naturally occurring precursor present in high concentrations in cruciferous vegetables. SFN inhibited in vitro replication of six strains of SARS-CoV-2, including Delta and Omicron, as well as that of the seasonal coronavirus HCoV-OC43. Further, SFN and remdesivir interacted synergistically to inhibit coronavirus infection in vitro. Prophylactic administration of SFN to K18-hACE2 mice prior to intranasal SARS-CoV-2 infection significantly decreased the viral load in the lungs and upper respiratory tract and reduced lung injury and pulmonary pathology compared to untreated infected mice. SFN treatment diminished immune cell activation in the lungs, including significantly lower recruitment of myeloid cells and a reduction in T cell activation and cytokine production. Our results suggest that SFN should be explored as a potential agent for the prevention or treatment of coronavirus infections.


Subject(s)
Antiviral Agents/therapeutic use , Common Cold/drug therapy , Coronavirus Infections/drug therapy , Coronavirus OC43, Human , Isothiocyanates/therapeutic use , SARS-CoV-2 , Sulfoxides/therapeutic use , Adenosine Monophosphate/analogs & derivatives , Adenosine Monophosphate/therapeutic use , Alanine/analogs & derivatives , Alanine/therapeutic use , Animals , Caco-2 Cells , Chlorocebus aethiops , Common Cold/virology , Coronavirus Infections/immunology , Coronavirus Infections/virology , Cytokines/immunology , Drug Synergism , Humans , Lung/immunology , Lung/virology , Macrophages, Alveolar/immunology , Male , Mice, Transgenic , Spleen/immunology , T-Lymphocytes/immunology , Vero Cells , Viral Load , COVID-19 Drug Treatment
12.
Front Immunol ; 12: 656419, 2021.
Article in English | MEDLINE | ID: covidwho-1506563

ABSTRACT

Tuberculosis (TB) is the global health problem with the second highest number of deaths from a communicable disease after COVID-19. Although TB is curable, poor health infrastructure, long and grueling TB treatments have led to the spread of TB pandemic with alarmingly increasing multidrug-resistant (MDR)-TB prevalence. Alternative host modulating therapies can be employed to improve TB drug efficacies or dampen the exaggerated inflammatory responses to improve lung function. Here, we investigated the adjunct therapy of natural immune-modulatory compound berberine in C57BL/6 mouse model of pulmonary TB. Berberine treatment did not affect Mtb growth in axenic cultures; however, it showed increased bacterial killing in primary murine bone marrow-derived macrophages and human monocyte-derived macrophages. Ad libitum berberine administration was beneficial to the host in combination with rifampicin and isoniazid. Berberine adjunctive treatment resulted in decreased lung pathology with no additive or synergistic effects on bacterial burdens in mice. Lung immune cell flow cytometry analysis showed that adjunctive berberine treatment decreased neutrophil, CD11b+ dendritic cell and recruited interstitial macrophage numbers. Late onset of adjunctive berberine treatment resulted in a similar phenotype with consistently reduced numbers of neutrophils both in lungs and the spleen. Together, our results suggest that berberine can be supplemented as an immunomodulatory agent depending on the disease stage and inflammatory status of the host.


Subject(s)
Antitubercular Agents/therapeutic use , Berberine/therapeutic use , Immunologic Factors/therapeutic use , Isoniazid/therapeutic use , Rifampin/therapeutic use , Tuberculosis, Pulmonary/drug therapy , Animals , Antitubercular Agents/pharmacology , Berberine/pharmacology , Cytokines/immunology , Dendritic Cells/drug effects , Drug Therapy, Combination , Female , Humans , Immunologic Factors/pharmacology , Isoniazid/pharmacology , Lung/drug effects , Lung/immunology , Lung/microbiology , Lung/pathology , Macrophages/drug effects , Macrophages/immunology , Male , Mice, Inbred C3H , Mice, Inbred C57BL , Mycobacterium tuberculosis/drug effects , Mycobacterium tuberculosis/growth & development , Neutrophils/drug effects , Neutrophils/immunology , Rifampin/pharmacology , Spleen/drug effects , Spleen/immunology , Spleen/microbiology , Tuberculosis, Pulmonary/immunology , Tuberculosis, Pulmonary/microbiology , Tuberculosis, Pulmonary/pathology
13.
Am J Respir Cell Mol Biol ; 66(2): 196-205, 2022 02.
Article in English | MEDLINE | ID: covidwho-1495786

ABSTRACT

Immunopathology occurs in the lung and spleen in fatal coronavirus disease (COVID-19), involving monocytes/macrophages and plasma cells. Antiinflammatory therapy reduces mortality, but additional therapeutic targets are required. We aimed to gain mechanistic insight into COVID-19 immunopathology by targeted proteomic analysis of pulmonary and splenic tissues. Lung parenchymal and splenic tissue was obtained from 13 postmortem examinations of patients with fatal COVID-19. Control tissue was obtained from cancer resection samples (lung) and deceased organ donors (spleen). Protein was extracted from tissue by phenol extraction. Olink multiplex immunoassay panels were used for protein detection and quantification. Proteins with increased abundance in the lung included MCP-3, antiviral TRIM21, and prothrombotic TYMP. OSM and EN-RAGE/S100A12 abundance was correlated and associated with inflammation severity. Unsupervised clustering identified "early viral" and "late inflammatory" clusters with distinct protein abundance profiles, and differences in illness duration before death and presence of viral RNA. In the spleen, lymphocyte chemotactic factors and CD8A were decreased in abundance, and proapoptotic factors were increased. B-cell receptor signaling pathway components and macrophage colony stimulating factor (CSF-1) were also increased. Additional evidence for a subset of host factors (including DDX58, OSM, TYMP, IL-18, MCP-3, and CSF-1) was provided by overlap between 1) differential abundance in spleen and lung tissue; 2) meta-analysis of existing datasets; and 3) plasma proteomic data. This proteomic analysis of lung parenchymal and splenic tissue from fatal COVID-19 provides mechanistic insight into tissue antiviral responses, inflammation and disease stages, macrophage involvement, pulmonary thrombosis, splenic B-cell activation, and lymphocyte depletion.


Subject(s)
COVID-19/immunology , Gene Expression Regulation/immunology , Lung/immunology , SARS-CoV-2/immunology , Spleen/immunology , Aged , Aged, 80 and over , Autopsy , Female , Humans , Inflammation/immunology , Male , Proteomics
14.
Int Immunopharmacol ; 101(Pt A): 108280, 2021 Dec.
Article in English | MEDLINE | ID: covidwho-1487771

ABSTRACT

The COVID-19 pandemic, caused by a highly virulent and transmissible pathogen, has proven to be devastating to society. Mucosal vaccines that can induce antigen-specific immune responses in both the systemic and mucosal compartments are considered an effective measure to overcome infectious diseases caused by pathogenic microbes. We have recently developed a nasal vaccine system using cationic liposomes composed of 1,2-dioleoyl-3-trimethylammonium-propane and cholesteryl 3ß-N-(dimethylaminoethyl)carbamate in mice. However, the comprehensive molecular mechanism(s), especially the host soluble mediator involved in this process, by which cationic liposomes promote antigen-specific mucosal immune responses, remain to be elucidated. Herein, we show that intranasal administration of cationic liposomes elicited interleukin-6 (IL-6) expression at the site of administration. Additionally, both nasal passages and splenocytes from mice nasally immunized with cationic liposomes plus ovalbumin (OVA) were polarized to produce IL-6 when re-stimulated with OVA in vitro. Furthermore, pretreatment with anti-IL-6R antibody, which blocks the biological activities of IL-6, attenuated the production of OVA-specific nasal immunoglobulin A (IgA) but not OVA-specific serum immunoglobulin G (IgG) responses. In this study, we demonstrated that IL-6, exerted by nasally administered cationic liposomes, plays a crucial role in antigen-specific IgA induction.


Subject(s)
Immunity, Mucosal/immunology , Immunoglobulin A/metabolism , Interleukin-6/immunology , Vaccines/immunology , Administration, Intranasal , Animals , Antibody Formation/drug effects , Antigens/immunology , COVID-19/prevention & control , Cations/immunology , Cations/therapeutic use , Fatty Acids, Monounsaturated/immunology , Fatty Acids, Monounsaturated/therapeutic use , Female , Immunity, Mucosal/drug effects , Immunoglobulin G/blood , Interleukin-6/antagonists & inhibitors , Interleukin-6/genetics , Interleukin-6/metabolism , Liposomes/immunology , Liposomes/therapeutic use , Mice , Nasal Mucosa/immunology , Nasal Mucosa/metabolism , Ovalbumin/immunology , Quaternary Ammonium Compounds/immunology , Quaternary Ammonium Compounds/therapeutic use , Spleen/metabolism , Vaccines/administration & dosage
15.
Viral Immunol ; 34(6): 416-420, 2021.
Article in English | MEDLINE | ID: covidwho-1475758

ABSTRACT

Coronavirus disease 2019 (COVID-19) is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which has infected millions of individuals in the world. However, the long-term effect of SARS-CoV-2 on the organs of recovered patients remains unclear. This study is to evaluate the impact of SARS-CoV-2 on the spleen and T lymphocytes. Seventy-six patients recovered from COVID-19, including 66 cases of moderate pneumonia and 10 cases of severe pneumonia were enrolled in the observation group. The control group consisted of 55 age-matched healthy subjects. The thickness and length of spleen were measured by using B-ultrasound and the levels of T lymphocytes were detected by flow cytometry. Results showed that the mean length of spleen in the observation group was 89.57 ± 11.49 mm, which was significantly reduced compared with that in the control group (103.82 ± 11.29 mm, p < 0.001). The mean thicknesses of spleen between observation group and control group were 29.97 ± 4.04 mm and 32.45 ± 4.49 mm, respectively, and the difference was significant (p < 0.001). However, no significant difference was observed in the size of spleen between common pneumonia and severe pneumonia (p > 0.05). In addition, the decreased count of T lymphocyte was observed in part of recovered patients. The counts of T suppressor lymphocytes in patients with severe pneumonia were significantly decreased compared with those with moderate pneumonia (p = 0.005). Therefore, these data indicate that SARS-CoV-2 infection affects the size of spleen and T lymphocytes.


Subject(s)
COVID-19/immunology , SARS-CoV-2 , Spleen/pathology , T-Lymphocytes/immunology , Adult , Aged , Female , Humans , Lymphocyte Count , Male , Middle Aged , Young Adult
16.
World J Gastroenterol ; 27(35): 5919-5931, 2021 Sep 21.
Article in English | MEDLINE | ID: covidwho-1438770

ABSTRACT

Coronavirus disease 2019 (COVID-19), caused by the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is an acute infectious disease that spreads mainly through the respiratory route. Besides interstitial pneumonia, a number of other clinical manifestations were noticed in COVID-19 patients. In particular, liver and spleen dysfunctions have been described both as complications of COVID-19 and as potential predisposing factors for severe COVID-19. Liver damage is rather common in COVID-19 patients, and it is most likely multifactorial, caused by the direct insult of SARS-CoV-2 to the liver by the cytokine storm triggered by the virus, by the use of hepatotoxic drugs, and as a consequence of hypoxia. Although generally mild, liver impairment has been found to be associated with a higher rate of intensive care unit admission. A higher mortality rate was reported among chronic liver disease patients. Instead, spleen impairment in patients with COVID-19 has been poorly described. The main anatomical changes are the architectural derangement of the B cell compartment, white pulp atrophy, and reduction or absence of lymphoid follicles, while, from a functional point of view, the IgM memory B cell pool is markedly depleted. The outcome of COVID-19 in asplenic or hyposplenic patients is yet to be defined. In this review, we will summarise the current knowledge regarding the impact of SARS-CoV-2 on the liver and spleen function, as well as the outcome of patients with a pre-existent liver disease or defective spleen function.


Subject(s)
COVID-19 , Liver Diseases , Humans , SARS-CoV-2 , Spleen
17.
Pathol Res Pract ; 227: 153610, 2021 Nov.
Article in English | MEDLINE | ID: covidwho-1401790

ABSTRACT

The coronavirus disease 2019(COVID-19) is recognized as systemic inflammatory response syndrome. It was demonstrated that a rapid increase of cytokines in the serum of COVID-19 patients is associated with the severity of disease. However, the mechanisms of the cytokine release are not clear. By using immunofluorescence staining we found that the number of CD11b positive immune cells including macrophages in the spleens of died COVID-19 patients, was significantly higher than that of the control patients. The incidence of apoptosis as measured by two apoptotic markers, TUNEL and cleaved caspase-3, in COVID-19 patients' spleen cells is higher than that in control patients. By double immunostaining CD11b or CD68 and SARS-CoV-2 spike protein, it was found that up to 67% of these immune cells were positive for spike protein, suggesting that viral infection might be associated with apoptosis in these cells. Besides, we also stained the autophagy-related molecules (p-Akt、p62 and BCL-2) in spleen tissues, the results showed that the number of positive cells was significantly higher in COVID-19 group. And compared with non-COVID-19 patients, autophagy may be inhibited in COVID-19 patients. Our research suggest that SARS-CoV-2 may result in a higher rate of apoptosis and a lower rate of autophagy of immune cells in the spleen of COVID-19 patients. These discoveries may increase our understanding of the pathogenesis of COVID-19.


Subject(s)
Apoptosis , Autophagy , COVID-19/pathology , SARS-CoV-2/pathogenicity , Spleen/pathology , Antigens, CD/analysis , Antigens, Differentiation, Myelomonocytic/analysis , Autopsy , Biomarkers/analysis , CD11b Antigen/analysis , COVID-19/immunology , COVID-19/mortality , COVID-19/virology , Case-Control Studies , Caspase 3/analysis , Host-Pathogen Interactions , Humans , Immunohistochemistry , In Situ Nick-End Labeling , Phosphorylation , Proto-Oncogene Proteins c-akt/analysis , Proto-Oncogene Proteins c-bcl-2/analysis , SARS-CoV-2/immunology , Sequestosome-1 Protein/analysis , Spike Glycoprotein, Coronavirus/analysis , Spleen/immunology , Spleen/virology
18.
Cell Res ; 31(8): 847-860, 2021 08.
Article in English | MEDLINE | ID: covidwho-1387284

ABSTRACT

Cytokine storm and multi-organ failure are the main causes of SARS-CoV-2-related death. However, the origin of excessive damages caused by SARS-CoV-2 remains largely unknown. Here we show that the SARS-CoV-2 envelope (2-E) protein alone is able to cause acute respiratory distress syndrome (ARDS)-like damages in vitro and in vivo. 2-E proteins were found to form a type of pH-sensitive cation channels in bilayer lipid membranes. As observed in SARS-CoV-2-infected cells, heterologous expression of 2-E channels induced rapid cell death in various susceptible cell types and robust secretion of cytokines and chemokines in macrophages. Intravenous administration of purified 2-E protein into mice caused ARDS-like pathological damages in lung and spleen. A dominant negative mutation lowering 2-E channel activity attenuated cell death and SARS-CoV-2 production. Newly identified channel inhibitors exhibited potent anti-SARS-CoV-2 activity and excellent cell protective activity in vitro and these activities were positively correlated with inhibition of 2-E channel. Importantly, prophylactic and therapeutic administration of the channel inhibitor effectively reduced both the viral load and secretion of inflammation cytokines in lungs of SARS-CoV-2-infected transgenic mice expressing human angiotensin-converting enzyme 2 (hACE-2). Our study supports that 2-E is a promising drug target against SARS-CoV-2.


Subject(s)
Antiviral Agents/metabolism , COVID-19/pathology , Coronavirus Envelope Proteins/metabolism , Respiratory Distress Syndrome/etiology , SARS-CoV-2/metabolism , Angiotensin-Converting Enzyme 2/genetics , Animals , Antiviral Agents/chemistry , Antiviral Agents/therapeutic use , Apoptosis , COVID-19/complications , COVID-19/virology , Coronavirus Envelope Proteins/antagonists & inhibitors , Coronavirus Envelope Proteins/genetics , Cytokines/metabolism , Disease Models, Animal , Half-Life , Humans , Lung/metabolism , Lung/pathology , Mice , Mice, Inbred C57BL , Mice, Transgenic , Mutagenesis, Site-Directed , SARS-CoV-2/isolation & purification , SARS-CoV-2/pathogenicity , Spleen/metabolism , Spleen/pathology , Viral Load , Virulence , COVID-19 Drug Treatment
19.
Ir J Med Sci ; 191(1): 81-91, 2022 Feb.
Article in English | MEDLINE | ID: covidwho-1384596

ABSTRACT

BACKGROUND: Although the lung is seen as the main target organ affected by SARS-CoV-2, other organs are also damaged. AIM: We aimed to determine the extrapulmonary findings of autopsies performed on cases with positive results with postmortem polymerase chain reaction test. METHODS: Pathological changes in extrapulmonary organs were examined with light microscopy. RESULTS: Heart, liver, spleen, kidney, pancreas, and central nervous system samples of these cases were evaluated. About 80% of the cases were men, and 20% were women. In the examination of heart, 28 of the cases had scar, 14 had acute myocardial infarction, 6 had acute and previous myocardial infarction findings, 2 had myocarditis, and 4 had interstitial mononuclear inflammatory cell infiltration. In the examination of the liver, portal inflammation was observed in 84 of the cases, steatosis in 54, centrilobular necrosis in 9, and capillary endotheliitis in the portal area in 7 of them. In the evaluation of the kidney, 37 cases had chronic pyelonephritis, 36 had tubular damage, 15 had tubulointerstitial necrosis, 16 had subcapsular microhemorrhage, 10 had capillary endothelitis, and 9 had a microvascular fibrin trombosis in their glomerular capillaries. In the central nervous system, 8 cases had infarction and liquefaction, 56 had perivascular petechial hemorrhage, 54 had acute hypoxic ischemic change, 3 had parenchymal microhemorrhage, and 52 had capillary endotheliitis. CONCLUSION: Autopsies play an important role in systematically examining the damage caused by the virus in all organs in order to elucidate the pathogenesis of SARS-CoV-2 infection and contribute to the clinical management of infected patients.


Subject(s)
COVID-19 , SARS-CoV-2 , Autopsy , Female , Humans , Lung , Male , Spleen
20.
Viruses ; 13(8)2021 08 04.
Article in English | MEDLINE | ID: covidwho-1359300

ABSTRACT

Transcriptomics, proteomics and pathogen-host interactomics data are being explored for the in silico-informed selection of drugs, prior to their functional evaluation. The effectiveness of this kind of strategy has been put to the test in the current COVID-19 pandemic, and it has been paying off, leading to a few drugs being rapidly repurposed as treatment against SARS-CoV-2 infection. Several neglected tropical diseases, for which treatment remains unavailable, would benefit from informed in silico investigations of drugs, as performed in this work for Dengue fever disease. We analyzed transcriptomic data in the key tissues of liver, spleen and blood profiles and verified that despite transcriptomic differences due to tissue specialization, the common mechanisms of action, "Adrenergic receptor antagonist", "ATPase inhibitor", "NF-kB pathway inhibitor" and "Serotonin receptor antagonist", were identified as druggable (e.g., oxprenolol, digoxin, auranofin and palonosetron, respectively) to oppose the effects of severe Dengue infection in these tissues. These are good candidates for future functional evaluation and clinical trials.


Subject(s)
Antiviral Agents/therapeutic use , Dengue/drug therapy , Transcriptome , Adenosine Triphosphatases/antagonists & inhibitors , Adrenergic Antagonists/pharmacology , Adrenergic Antagonists/therapeutic use , Antiviral Agents/pharmacology , Brain/metabolism , Computer Simulation , Dengue/blood , Dengue/genetics , Dengue/metabolism , Drug Discovery , Drug Evaluation, Preclinical , Drug Repositioning , Humans , Liver/metabolism , Metabolic Networks and Pathways/drug effects , NF-kappa B/metabolism , Serotonin Antagonists/pharmacology , Serotonin Antagonists/therapeutic use , Severe Dengue/blood , Severe Dengue/drug therapy , Severe Dengue/genetics , Severe Dengue/metabolism , Spleen/metabolism
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