scholarly journals Neutralizing antibody-dependent and -independent immune responses against SARS-CoV-2 in cynomolgus macaques

2020 ◽  
Author(s):  
Hirohito Ishigaki ◽  
Misako Nakayama ◽  
Yoshinori Kitagawa ◽  
Cong Thanh Nguyen ◽  
Kaori Hayashi ◽  
...  
Keyword(s):  
T Lymphocytes ◽  
Clinical Signs ◽  
Neutralizing Antibody ◽  
Viral Pneumonia ◽  
The Other ◽  
N Protein ◽  
Cynomolgus Macaques ◽  
Life Threatening ◽  
Ifn Γ

AbstractSevere acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infectious disease (COVID-19) has been threatening the world because of severe symptoms and relatively high mortality. To develop vaccines and antiviral drugs for COVID-19, an animal model of SARS-CoV-2 infection is required to evaluate the efficacy of prophylactics and therapeutics in vivo. Therefore, we examined the pathogenicity of SARS-CoV-2 in cynomolgus macaques until 28 days after virus inoculation in the present study. Cynomolgus macaques showed body temperature rises after infection and X-ray radiographic viral pneumonia was observed in one of three macaques. However, none of the macaques showed life-threatening clinical signs of disease corresponding that approximately 80% of human patients did not show a critical disease in COVID-19. A neutralizing antibody against SARS-CoV-2 and T-lymphocytes that produced interferon (IFN)-γ and interleukin (IL)-2 specifically for SARS-CoV-2 N protein were detected on day 14 in the macaque that showed viral pneumonia. On the other hand, in the other macaques, in which a neutralizing antibody was not detected, T-lymphocytes that produced IFN-γ specifically for SARS-CoV-2 N protein increased on day 7 to day 14 prior to an increase in the number of T-lymphocytes that produced IL-2. These results suggest that not only a neutralizing antibody but also cellular immunity augmented by IFN-γ has a role in the elimination of SARS-CoV-2. Thus, because of the mild clinical signs of disease and low/no antibody responses against SARS-CoV-2 in two thirds of the macaques, cynomolgus macaques are appropriate to extrapolate human responses in vaccine and drug development.Author SummarySevere acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infectious disease (COVID-19) has been threatening the world. To develop vaccines and antiviral drugs for COVID-19, an animal model of SARS-CoV-2 infection is required to evaluate their efficacy in vivo. Therefore, we examined the pathogenicity of SARS-CoV-2 in a non-human primate model until 28 days after virus inoculation. Cynomolgus macaques showed a fever after infection and X-ray radiographic viral pneumonia was observed in one of three macaques. However, none of the macaques showed life-threatening symptoms. A neutralizing antibody against SARS-CoV-2 and T-lymphocytes that produced interferon (IFN)-γ and interleukin (IL)-2 specifically for SARS-CoV-2 protein were detected on day 14 in the macaque that showed viral pneumonia. In the other macaques, in which a neutralizing antibody was not detected, T-lymphocytes that produced IFN-γ specifically for SARS-CoV-2 N protein increased on day 7 to day 14. These results suggest that not only a neutralizing antibody but also cellular immunity augmented by IFN-γ has a role in the elimination of SARS-CoV-2. Thus, because of the mild symptoms and low/no antibody responses against SARS-CoV-2 in two thirds of the macaques, cynomolgus macaques are appropriate to extrapolate human responses in vaccine and drug development.

scholarly journals Thyrotoxic Periodic Paralysis—A Misleading Challenge in the Emergency Department

Diagnostics ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 316 ◽  
Author(s):  
Stefana Bilha ◽  
Ovidiu Mitu ◽  
Laura Teodoriu ◽  
Cristian Haba ◽  
Cristina Preda
Keyword(s):  
Clinical Signs ◽  
Initial Therapy ◽  
Periodic Paralysis ◽  
The Other ◽  
Motor Deficit ◽  
Antithyroid Drugs ◽  
Thyrotoxic Periodic Paralysis ◽  
First Case ◽  
Life Threatening ◽  
Antithyroid Agents

Despite its’ life-threatening potential due to cardiac severe dysrhythmia in the context of severe hypokalemia, thyrotoxic periodic paralysis (TPP) often goes unrecognized. Although classically confined to young Asian men, it can occur irrespective of age, sex, and race. We report a short series of three cases of TPP as first presentation of Graves’ disease in a young Caucasian male and in two Caucasian elderly and middle-aged women, respectively. The first patient developed malignant ventricular arrhythmias due to severe hypokalemia and was defibrillated, with recovery after prompt potassium correction and administration of antithyroid agents and propranolol. The other two cases developed persistent hypokalemia despite adequate potassium chloride (KCl) repletion, with slow recovery of motor deficit and serum potassium normalization up to day 5. In the first case, long-term euthyroid state was achieved via total thyroidectomy due to the presence of a suspicious nodule that proved to be malignant. In the other two cases, medical treatment was the choice of therapy for thyrotoxicosis. None experienced recurrent TPP. Thyroid hormone evaluation is mandatory in the presence of hypokalemic paralysis, even in the absence of clinical signs of thyrotoxicosis. If TPP is confirmed, initial therapy should comprise antithyroid drugs and propranolol, besides hypokalemia correction.

scholarly journals IFN-γ down-regulates the PD-1 expression and assist nivolumab in PD-1-blockade effect on CD8+ T-lymphocytes in pancreatic cancer

BMC Cancer ◽  
2019 ◽  
Vol 19 (1) ◽  
Author(s):  
Guoping Ding ◽  
Tao Shen ◽  
Chen Yan ◽  
Mingjie Zhang ◽  
Zhengrong Wu ◽  
...  
Keyword(s):  
Pancreatic Cancer ◽  
T Lymphocytes ◽  
Ductal Adenocarcinoma ◽  
Cytotoxic Activities ◽  
Dependent Manner ◽  
Concentration Dependent Manner ◽  
Cd8 T Lymphocytes ◽  
Ifn Γ

Abstract Background Pancreatic cancer is characterized by a highly immunosuppressive tumor microenvironment and evasion of immune surveillance. Although programmed cell death 1 receptor (PD-1) blockade has achieved certain success in immunogenic cancers, the responses to the PD-1 antibody are not effective or sustained in patients with pancreatic cancer. Methods Firstly, PD-1 expressions on peripheral CD8+ T-lymphocytes of patients with pancreatic cancer and healthy donors were measured. In in vitro study, peripheral T-lymphocytes were isolated and treated with nivolumab and/or interferon-γ, and next, PD-1-blockade effects, proliferations, cytokine secretions and cytotoxic activities were tested after different treatments. In in vivo study, mice bearing subcutaneous pancreatic cancer cell lines were treated with induced T-lymphocytes and tumor sizes were measured. Results PD-1 protein expression is increased on peripheral CD8+ T cells in patients with pancreatic ductal adenocarcinoma compared with that in health donor. PD-1 expression on CD8+ T-lymphocytes was decreased by nivolumab in a concentration-dependent manner in vitro. IFN-γ could directly down-regulate expression of PD-1 in vitro. Furthermore, the combination therapy of nivolumab and IFN-γ resulted in greatest effect of PD-1-blockde (1.73 ± 0.78), compared with IFN-γ along (18.63 ± 0.82) and nivolumab along (13.65 ± 1.22). Moreover, the effects of nivolumab plus IFN-γ largest promoted the T-lymphocytes function of proliferations, cytokine secretions and cytotoxic activities. Most importantly, T-lymphocytes induced by nivolumab plus IFN-γ presented the best repression of tumor growth. Conclusions IFN-γ plus a PD-1-blockading agent could enhance the immunologic function and might play a crucial role in effective adoptive transfer treatments of pancreatic cancer.

Opposing Effects of PD-1/PD-L1/L2 Engagement and IFN-γ/TNF-α in the Treatment of AML w/ Anti-CD33 Chimeric Antigen Receptor-Modified T Cells

Blood ◽  
2016 ◽  
Vol 128 (22) ◽  
pp. 5891-5891
Author(s):  
Jacob Halum Basham ◽  
Terrence L. Geiger
Keyword(s):  
T Cells ◽  
T Cell ◽  
T Lymphocytes ◽  
Chimeric Antigen Receptor ◽  
Short Term ◽  
Car T Cells ◽  
Tnf Α ◽  
Car T ◽  
Ifn Γ

Abstract Chimeric antigen receptor-modified T lymphocytes (CART cells) have shown benefit as an adjuvant immunotherapy in the treatment of B cell malignancies. This success of re-targeted T cells has not been extended to other hematologic malignancies. We have developed an immunotherapeutic approach to treat acute myeloid leukemia (AML) using CAR T cells re-directed against the myeloid-specific antigen CD33 (CART-33). CART-33 cells are potent and specific in eliminating AML cells in vitro and in vivo. Despite this, CART-33 cells have shown poor in vivo expansion and persistence in NOD-SCID IL2rγ (-/-) (NSG) AML xenograft models. To address the reason for this, we assessed the impact of AML-expressed programmed death ligands 1 & 2 (PD-L1/2) on CART-33 cell activity. PD-L1 inhibits T cell functions upon binding PD-1, which is upregulated with T cell activation. Less is known about PD-L2's effect. Interferon-gamma (IFN-γ), a primary effector cytokine secreted by CD4+ and CD8+ effector T cells, is a known potent inducer of PD-L1 on AML blasts. Using AML cell lines U937, Oci-AML3, CMK, and MV4-11 we show that IFN-γ, TNF-α, and activated CART-33 supernatant can induce up-regulation of PD-L1 and PD-L2 on AML. IFN-γ and TNF-α synergize strongly in up-regulating PD-1 ligands on AML. The kinetics and induction of PD-L2 are distinct from that of PD-L1. Although PD-L1 is well documented to suppress T cell function via ligation of T cell expressed PD-1, induction of PD-L1/L2 had no effect on the cytolytic activity of CART-33 cells against AML in short term (<48 h) cultures. Paradoxically, 24 hr pre-treatment of AML with either IFN-γ or CART-33 supernatant increased AML susceptibility to killing by CART-33 cells despite elevated expression of PD-L1/L2 by AML. Our results highlight the regulatory complexity of AML cytolysis by re-targeted T lymphocytes, and argue that tumor-expressed PD-L1 and PD-L2 impacts the sustainability, but not short-term killing activity, of adoptively transferred CAR T cells in the treatment of AML. Disclosures No relevant conflicts of interest to declare.

scholarly journals Investigation of the Role of CD8+ T Cells in Bovine Tuberculosis In Vivo

2003 ◽  
Vol 71 (8) ◽  
pp. 4297-4303 ◽  
Author(s):  
B. Villarreal-Ramos ◽  
M. McAulay ◽  
V. Chance ◽  
M. Martin ◽  
J. Morgan ◽  
...  
Keyword(s):  
Lymph Node ◽  
Bovine Tuberculosis ◽  
The Other ◽  
Cd8 Cells ◽  
Cd8 Cell ◽  
Ifn Γ ◽  
Mycobacterial Antigens

ABSTRACT Mycobacterium bovis is the causative agent of bovine tuberculosis (TB), and it has the potential to induce disease in humans. CD8+ T cells (CD8 cells) have been shown to respond to mycobacterial antigens in humans, cattle, and mice. In mice, CD8 cells have been shown to play a role in protection against mycobacterial infection. To determine the role of CD8 cells in bovine TB in vivo, two groups of calves were infected with the virulent M. bovis strain AF2122/97. After infection, one group was injected with a CD8 cell-depleting monoclonal antibody (MAb), and the other group was injected with an isotype control MAb. Immune responses to mycobacterial antigens were measured weekly in vitro. After 8 weeks, the animals were killed, and postmortem examinations were carried out. In vitro proliferation responses were similar in both calf groups, but in vitro gamma interferon (IFN-γ) production in 24-h whole-blood cultures was significantly higher in control cattle than in CD8 cell-depleted calves. Postmortem examination showed that calves in both groups had developed comparable TB lesions in the lower respiratory tract and associated lymph nodes. Head lymph node lesion scores, on the other hand, were higher in control calves than in CD8 cell-depleted calves. Furthermore, there was significant correlation between the level of IFN-γ and the head lymph node lesion score. These experiments indicate that CD8 cells play a role in the immune response to M. bovis in cattle by contributing to the IFN-γ response. However, CD8 cells may also play a deleterious role by contributing to the immunopathology of bovine TB.

scholarly journals Induction and Regulation of Th1-Inducing Cytokines by Bacterial DNA, Lipopolysaccharide, and Heat-Inactivated Bacteria

1999 ◽  
Vol 67 (12) ◽  
pp. 6257-6263 ◽  
Author(s):  
L.-Y. Huang ◽  
A. M. Krieg ◽  
N. Eller ◽  
D. E. Scott
Keyword(s):  
Neutralizing Antibody ◽  
Interleukin 12 ◽  
Spleen Cells ◽  
In Vivo Experiments ◽  
Time Period ◽  
Murine Spleen ◽  
Ifn Γ ◽  
Favorable Conditions ◽  
Th1 Immune Responses

ABSTRACT Th1 immune responses, characterized by production of gamma interferon (IFN-γ), are associated with protective immunity to viruses and intracellular bacteria. Heat-killed Brucella abortus promotes secretion of Th1-inducing cytokines such as interleukin-12 (IL-12) and IFN-γ and has been used as a carrier to induce Th1 responses to vaccines. To explore which bacterial constituents could mediate this response and how it is regulated, murine spleen cells were cultured with B. abortus derived DNA, lipopolysaccharide (LPS), or whole killed organisms. Each constituent induced similar, substantial amounts of IL-10. However, only B. abortus and B. abortus DNA induced high levels of IFN-γ and IL-12. B. abortus and B. abortus DNA-stimulated IL-12 production was maximal by 6 to 18 h, while IL-10 production steadily accumulated over this time period. These kinetics suggested that IL-10 may eventually downmodulate the Th1-like cytokine response to B. abortus and B. abortus DNA, which was confirmed by using neutralizing antibody. In the absence of IL-10, B. abortus LPS induced strong IFN-γ responses, but IL-12 p70 levels were still undetectable from BALB/c spleen cells. LPS induced IL-12 if the spleen cells were primed with IFN-γ and IL-10 was neutralized, indicating that LPS can stimulate IL-12 production under the most favorable conditions. Responses to Escherichia coli LPS and DNA mirrored the responses to B. abortus components, suggesting that immune effects observed with these constituents may be generalizable to many microbial species. In vivo experiments demonstrated the same hierarchy of responses for IL-12 production. These findings support the likelihood that microbial components, if used as carriers or adjuvants, can differ substantially in their ability to effect a Th1 response.

scholarly journals Induction of Gamma Interferon and Nitric Oxide by Truncated Pneumolysin That Lacks Pore-Forming Activity

2002 ◽  
Vol 70 (1) ◽  
pp. 107-113 ◽  
Author(s):  
Hisashi Baba ◽  
Ikuo Kawamura ◽  
Chikara Kohda ◽  
Takamasa Nomura ◽  
Yutaka Ito ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Neutralizing Antibody ◽  
Cytolytic Activity ◽  
Gamma Interferon ◽  
Full Length ◽  
No Production ◽  
Spleen Cells ◽  
Ifn Γ ◽  
Oxide Synthase

ABSTRACT Pneumolysin (PLY), an important virulence factor of Streptococcus pneumoniae, is known to exert various effects on the host immune cells, including cytokine induction, in addition to its known cytolytic activity as a member of the thiol-activated cytolysins. It is of interest to determine whether cytolytic activity is involved in triggering the cytokine production. In this study, we constructed full-length recombinant PLY and noncytolytic truncated PLYs with C-terminal deletions to examine the response of spleen cells to these PLY preparations. When cytolytic activity was blocked by treatment with cholesterol, full-length PLY was capable of inducing gamma interferon (IFN-γ) production. Truncated PLYs that originally exhibited no cytolytic activity were also active in IFN-γ induction. Therefore, the IFN-γ-inducing ability of PLY appeared to be independent of the cytolytic activity. Furthermore, IFN-γ-inducing preparations were also capable of inducing nitric oxide synthase expression and nitric oxide (NO) production, and the addition of neutralizing antibody to IFN-γ abolished the NO production. These results clearly demonstrated that PLY is capable of inducing IFN-γ production in spleen cells by a mechanism different from pore formation and that the induced IFN-γ stimulates NO production. These findings were discussed with reference to the contribution of PLY to the virulence of S. pneumoniae in vivo.

scholarly journals Involvement of CD4+ Th1 Cells in Systemic Immunity Protective against Primary and Secondary Challenges withTrypanosoma cruzi

2000 ◽  
Vol 68 (1) ◽  
pp. 197-204 ◽  
Author(s):  
Daniel F. Hoft ◽  
Anita R. Schnapp ◽  
Christopher S. Eickhoff ◽  
Stanford T. Roodman
Keyword(s):  
T Lymphocytes ◽  
Th1 Cells ◽  
Intracellular Parasite ◽  
Systemic Immunity ◽  
Effector Functions ◽  
Th2 Responses ◽  
Parasite Replication ◽  
Ifn Γ ◽  
Th1 And Th2

ABSTRACT In general, gamma interferon (IFN-γ)-producing CD4+Th1 cells are important for the immunological control of intracellular pathogens. We previously demonstrated an association between parasite-specific induction of IFN-γ responses and resistance to the intracellular protozoan Trypanosoma cruzi. To investigate a potential causal relationship between Th1 responses andT. cruzi resistance, we studied the ability of Th1 cells to protect susceptible BALB/c mice against virulent parasite challenges. We developed immunization protocols capable of inducing polarized Th1 and Th2 responses in vivo. Induction of parasite-specific Th1 responses, but not Th2 responses, protected BALB/c mice against virulent T. cruzi challenges. We generated T. cruzi-specific CD4+ Th1 and Th2 cell lines from BALB/c mice that were activated by infected macrophages to produce their corresponding cytokine response profiles. Th1 cells, but not Th2 cells, induced nitric oxide production and inhibited intracellular parasite replication in T. cruzi-infected macrophages. Despite the ability to inhibit parasite replication in vitro, Th1 cells alone could not adoptively transfer protection againstT. cruzi to SCID mice. In addition, despite the fact that the adoptive transfer of CD4+ T lymphocytes was shown to be necessary for the development of immunity protective against primary T. cruzi infection in our SCID mouse model, protective secondary effector functions could be transferred to SCID mice from memory-immune BALB/c mice in the absence of CD4+ T lymphocytes. These results indicate that, although CD4+ Th1 cells can directly inhibit intracellular parasite replication, a more important role for these cells in T. cruzi systemic immunity may be to provide helper activity for the development of other effector functions protective in vivo.

scholarly journals Cytokines Differently Define the Immunomodulation of Mesenchymal Stem Cells from the Periodontal Ligament

Cells ◽  
2020 ◽  
Vol 9 (5) ◽  
pp. 1222 ◽  
Author(s):  
Christian Behm ◽  
Alice Blufstein ◽  
Johannes Gahn ◽  
Michael Nemec ◽  
Andreas Moritz ◽  
...  
Keyword(s):  
Stem Cells ◽  
T Lymphocytes ◽  
Periodontal Ligament ◽  
Periodontal Ligament Stem Cells ◽  
T Lymphocyte Proliferation ◽  
Tnf Α ◽  
Proliferation And Apoptosis ◽  
Cytokine Milieu ◽  
Ifn Γ

Human periodontal ligament stem cells (hPDLSCs) play an important role in periodontal tissue homeostasis and regeneration. The function of these cells in vivo depends largely on their immunomodulatory ability, which is reciprocally regulated by immune cells via cytokines, particularly interferon (IFN)-γ, tumor necrosis factor (TNF)-α, and interleukin (IL)-1β. Different cytokines activate distinct signaling pathways and might differently affect immunomodulatory activities of hPDLSCs. This study directly compared the effect of IFN-γ, TNF-α, or IL-1β treated primary hPDLSCs on allogenic CD4+ T lymphocyte proliferation and apoptosis in an indirect co-culture model. The effects of IFN-γ, TNF-α, and IL-1β on the expression of specific immunomodulatory factors such as intoleamine-2,3-dioxygenase-1 (IDO-1), prostaglandin E2 (PGE2), and programmed cell death 1 ligand 1 (PD-L1) and ligand 2 (PD-L2) in hPDLSCs were compared. The contribution of different immunomodulatory mediators to the immunomodulatory effects of hPDLSCs in the indirect co-culture experiments was assessed using specific inhibitors. Proliferation of CD4+ T lymphocytes was inhibited by hPDLSCs, and this effect was strongly enhanced by IFN-γ and IL-1β but not by TNF-α. Apoptosis of CD4+ T lymphocytes was decreased by hPDLSCs per se. This effect was counteracted by IFN-γ or IL-1β. Additionally, IFN-γ, TNF-α, and IL-1β differently regulated all investigated immunomediators in hPDLSCs. Pharmacological inhibition of immunomediators showed that their contribution in regulating CD4+ T lymphocytes depends on the cytokine milieu. Our data indicate that inflammatory cytokines activate specific immunomodulatory mechanisms in hPDLSCs and the expression of particular immunomodulatory factors, which underlies a complex reciprocal interaction between hPDLSCs and CD4+ T lymphocytes.

scholarly journals Different Profiles of Antibodies and Cytokines Were Found Between Severe and Moderate COVID-19 Patients

2021 ◽  
Vol 12 ◽  
Author(s):  
Yaolin Guo ◽  
Tianyi Li ◽  
Xinyi Xia ◽  
Bin Su ◽  
Hanping Li ◽  
...  
Keyword(s):  
Neutralizing Antibody ◽  
Healthy Individuals ◽  
S Protein ◽  
Elisa System ◽  
N Protein ◽  
Tnf Α ◽  
Significant Difference ◽  
Positive Rate ◽  
Antibody Titers ◽  
Ifn Γ

ObjectivesOur objective was to determine the antibody and cytokine profiles in different COVID-19 patients.MethodsCOVID-19 patients with different clinical classifications were enrolled in this study. The level of IgG antibodies, IgA, IgM, IgE, and IgG subclasses targeting N and S proteins were tested using ELISA. Neutralizing antibody titers were determined by using a toxin neutralization assay (TNA) with live SARS-CoV-2. The concentrations of 8 cytokines, including IL-2, IL-4, IL-6, IL-10, CCL2, CXCL10, IFN-γ, and TNF-α, were measured using the Protein Sample Ella-Simple ELISA system. The differences in antibodies and cytokines between severe and moderate patients were compared by t-tests or Mann-Whitney tests.ResultsA total of 79 COVID-19 patients, including 49 moderate patients and 30 severe patients, were enrolled. Compared with those in moderate patients, neutralizing antibody and IgG-S antibody titers in severe patients were significantly higher. The concentration of IgG-N antibody was significantly higher than that of IgG-S antibody in COVID-19 patients. There was a significant difference in the distribution of IgG subclass antibodies between moderate patients and severe patients. The positive ratio of anti-S protein IgG3 is significantly more than anti-N protein IgG3, while the anti-S protein IgG4 positive rate is significantly less than the anti-N protein IgG4 positive rate. IL-2 was lower in COVID-19 patients than in healthy individuals, while IL-4, IL-6, CCL2, IFN-γ, and TNF-α were higher in COVID-19 patients than in healthy individuals. IL-6 was significantly higher in severe patients than in moderate patients. The antibody level of anti-S protein was positively correlated with the titer of neutralizing antibody, but there was no relationship between cytokines and neutralizing antibody.ConclusionsOur findings show the severe COVID-19 patients’ antibody levels were stronger than those of moderate patients, and a cytokine storm is associated with COVID-19 severity. There was a difference in immunoglobulin type between anti-S protein antibodies and anti-N protein antibodies in COVID-19 patients. And clarified the value of the profile in critical prevention.

scholarly journals Cryptococcus gattii VGI Subtypes: Geographical Distribution, Molecular Traits, and Virulence Difference

2021 ◽  
Author(s):  
Xinying Xue ◽  
Wei Tang ◽  
Xuelei Zang ◽  
Weixin Ke ◽  
Yuxia Liu ◽  
...  
Keyword(s):  
Geographical Distribution ◽  
Species Complex ◽  
Reference Genome ◽  
De Novo ◽  
Cryptococcus Gattii ◽  
The Other ◽  
Molecular Type ◽  
Life Threatening

Abstract Background: As a life-threatening fungus, Cryptococcus gattii (C gattii) species complex is emerging worldwide. However, the geographical distribution, molecular traits, and virulence difference are poorly characterized in China.Results: From 2011 to 2017, we collected 32 strains of C gattii from 18 hospitals across China, of which 27 [84·4%] strains molecular traits were profiled by whole-genome sequencing (WGS) and multi-locus sequence typing (MLST) and compared with strains previously described in China from 2006 to 2020. Totally 119 clinical cases caused by C gattii strains (87 in previous reports and 32 in our study) distributed widely in 20 provincial-level administrative regions of China, of which 114 strains molecular types were obtained. The majority molecular type was VGI (81/114, 71·1%) and the other was VGII (33/114, 28·9%). Four major subtypes of VGI (VGIa, VGIb, VGIc, and VGId) were revealed from global C gattii VGI (n=308), respectively accounting for 52·9% (163/308), 36·0% (111/308), 3·9% (12/308), and 4·2% (13/308). The other nine strains could not be assigned to these four subtypes clearly. Our clinical data suggested that VGIb cases had a worse clinical outcome than VGIa, which was consistent with in vitro and in vivo experiments. In addition, a candidate virulence SNP on SOD2 in VGIa was initially identified by comparing high-quality de novo reference genome.Conclusions: The geographical distribution of C gattii species complex was first described in China. C gattii VGI could be clearly segregated into four major subtypes based on genomics profiles and VGIb was more virulent than VGIa in China. Our study suggests the molecular type of C gattii is necessary for personalized treatment in clinic.

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