| 1. |
- Bhattacharya, Pradyot, et al.
(författare)
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Complement opsonization of HIV affects primary infection of human colorectal mucosa and subsequent activation of T cells
- 2020
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Ingår i: eLIFE. - Cambridge, United Kingdom : ELIFE SCIENCES PUBLICATIONS LTD. - 2050-084X. ; 9
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Tidskriftsartikel (refereegranskat)abstract
- HIV transmission via genital and colorectal mucosa are the most common routes of dissemination. Here, we explored the effects of free and complement-opsonized HIV on colorectal tissue. Initially, there was higher antiviral responses in the free HIV compared to complementopsonized virus. The mucosal transcriptional response at 24 hr revealed the involvement of activated T cells, which was mirrored in cellular responses observed at 96 hr in isolated mucosal T cells. Further, HIV exposure led to skewing of T cell phenotypes predominantly to inflammatory CD4+ T cells, that is Th17 and Th1Th17 subsets. Of note, HIV exposure created an environment that altered the CD8+ T cell phenotype, for example expression of regulatory factors, especially when the virions were opsonized with complement factors. Our findings suggest that HIV-opsonization alters the activation and signaling pathways in the colorectal mucosa, which promotes viral establishment by creating an environment that stimulates mucosal T cell activation and inflammatory Th cells.
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| 2. |
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| 3. |
- Crisci, Elisa, et al.
(författare)
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HSV-2 Cellular Programming Enables Productive HIV Infection in Dendritic Cells
- 2019
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Ingår i: Frontiers in Immunology. - : Frontiers Media SA. - 1664-3224. ; 10
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Tidskriftsartikel (refereegranskat)abstract
- Genital herpes is a common sexually transmitted infection caused by herpes simplex virus type 2 (HSV-2). Genital herpes significantly enhances the acquisition and transmission of HIV-1 by creating a microenvironment that supports HIV infection in the host. Dendritic cells (DCs) represent one of the first innate cell types that encounter HIV-1 and HSV-2 in the genital mucosa. HSV-2 infection has been shown to modulate DCs, rendering them more receptive to HIV infection. Here, we investigated the potential mechanisms underlying HSV-2-mediated augmentation of HIV-1 infection. We demonstrated that the presence of HSV-2 enhanced productive HIV-1 infection of DCs and boosted inflammatory and antiviral responses. The HSV-2 augmented HIV-1 infection required intact HSV-2 DNA, but not active HSV-2 DNA replication. Furthermore, the augmented HIV infection of DCs involved the cGAS-STING pathway. Interestingly, we could not see any involvement of TLR2 or TLR3 nor suppression of infection by IFN-beta production. The conditioning by HSV-2 in dual exposed DCs decreased protein expression of IFI16, cGAS, STING, and TBK1, which is associated with signaling through the STING pathway. Dual exposure to HSV-2 and HIV-1 gave decreased levels of several HIV-1 restriction factors, especially SAMHD1, TREX1, and APOBEC3G. Activation of the STING pathway in DCs by exposure to both HSV-2 and HIV-1 most likely led to the proteolytic degradation of the HIV-1 restriction factors SAMHD1, TREX1, and APOBEC3G, which should release their normal restriction of HIV infection in DCs. This released their normal restriction of HIV infection in DCs. We showed that HSV-2 reprogramming of cellular signaling pathways and protein expression levels in the DCs provided a setting where HIV-1 can establish a higher productive infection in the DCs. In conclusion, HSV-2 reprogramming opens up DCs for HIV-1 infection and creates a microenvironment favoring HIV-1 transmission.
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| 4. |
- Ellegård, Rada, 1985-, et al.
(författare)
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Complement-Opsonized HIV-1 Alters Cross Talk Between Dendritic Cells and Natural Killer (NK) Cells to Inhibit NK Killing and to Upregulate PD-1, CXCR3, and CCR4 on T Cells
- 2018
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Ingår i: Frontiers in Immunology. - : FRONTIERS MEDIA SA. - 1664-3224. ; 9
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Tidskriftsartikel (refereegranskat)abstract
- Dendritic cells (DCs), natural killer (NK) cells, and T cells play critical roles during primary HIV-1 exposure at the mucosa, where the viral particles become coated with complement fragments and mucosa-associated antibodies. The microenvironment together with subsequent interactions between these cells and HIV at the mucosal site of infection will determine the quality of immune response that ensues adaptive activation. Here, we investigated how complement and immunoglobulin opsonization influences the responses triggered in DCs and NK cells, how this affects their cross talk, and what T cell phenotypes are induced to expand following the interaction. Our results showed that DCs exposed to complement-opsonized HIV (C-HIV) were less mature and had a poor ability to trigger IFN-driven NK cell activation. In addition, when the DCs were exposed to C-HIV, the cytotolytic potentials of both NK cells and CD8 T cells were markedly suppressed. The expression of PD-1 as well as co-expression of negative immune checkpoints TIM-3 and LAG-3 on PD-1 positive cells were increased on both CD4 as well as CD8 T cells upon interaction with and priming by NK-DC cross talk cultures exposed to C-HIV. In addition, stimulation by NK-DC cross talk cultures exposed to C-HIV led to the upregulation of CD38, CXCR3, and CCR4 on T cells. Together, the immune modulation induced during the presence of complement on viral surfaces is likely to favor HIV establishment, dissemination, and viral pathogenesis.
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| 5. |
- Enocsson, Helena, et al.
(författare)
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Comparison of Surrogate Markers of the Type I Interferon Response and Their Ability to Mirror Disease Activity in Systemic Lupus Erythematosus
- 2021
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Ingår i: Frontiers in Immunology. - : Frontiers Media S.A.. - 1664-3224. ; 12
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Tidskriftsartikel (refereegranskat)abstract
- Objectives: Type I interferons (IFNs) are central and reflective of disease activity in systemic lupus erythematosus (SLE). However, IFN-alpha levels are notoriously difficult to measure and the type I IFN gene signature (IGS) is not yet available in clinical routine. This study evaluates galectin-9 and an array of chemokines/cytokines in their potential as surrogate markers of type I IFN and/or SLE disease activity.Methods: Healthy controls and well-characterized Swedish SLE patients from two cross-sectional cohorts (n=181; n=59) were included, and a subgroup (n=21) was longitudinally followed. Chemokine/cytokine responses in immune complex triggered IFN-alpha activity was studied in healthy donor peripheral blood mononuclear cells (PBMC). Levels of chemokines/cytokines and galectin-9 were measured by immunoassays. Gene expression was quantified by qPCR.Results: The IGS was significantly (p<0.01) correlated with galectin-9 (rho=0.54) and CXCL10 (rho=0.37) levels whereas serum IFN-alpha correlated with galectin-9 (rho=0.36), CXCL10 (rho=0.39), CCL19 (rho=0.26) and CCL2 (rho=0.19). The strongest correlation was observed between galectin-9 and TNF (rho=0.56). IFN-alpha and disease activity (SLEDAI-2K) were correlated (rho=0.20) at cross-sectional analysis, but no significant associations were found between SLEDAI-2K and galectin-9 or chemokines. Several inflammatory mediators increased at disease exacerbation although CCL19, CXCL11, CXCL10, IL-10 and IL-1 receptor antagonist were most pronounced. Immune complex-stimulation of PBMC increased the production of CCL2, CXCL8 and TNF.Conclusion: Galectin-9 and CXCL10 were associated with type I IFN in SLE but correlated stronger with TNF. None of the investigated biomarkers showed a convincing association with disease activity, although CXCL10 and CCL19 performed best in this regard.
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| 6. |
- Govender, Melissa, et al.
(författare)
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T cell perturbations persist for at least 6 months following hospitalization for COVID-19
- 2022
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Ingår i: Frontiers in Immunology. - : Frontiers Media SA. - 1664-3224. ; 13
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Tidskriftsartikel (refereegranskat)abstract
- COVID-19 is being extensively studied, and much remains unknown regarding the long-term consequences of the disease on immune cells. The different arms of the immune system are interlinked, with humoral responses and the production of high-affinity antibodies being largely dependent on T cell immunity. Here, we longitudinally explored the effect COVID-19 has on T cell populations and the virus-specific T cells, as well as neutralizing antibody responses, for 6-7 months following hospitalization. The CD8(+) TEMRA and exhausted CD57(+) CD8(+) T cells were markedly affected with elevated levels that lasted long into convalescence. Further, markers associated with T cell activation were upregulated at inclusion, and in the case of CD69(+) CD4(+) T cells this lasted all through the study duration. The levels of T cells expressing negative immune checkpoint molecules were increased in COVID-19 patients and sustained for a prolonged duration following recovery. Within 2-3 weeks after symptom onset, all COVID-19 patients developed anti-nucleocapsid IgG and spike-neutralizing IgG as well as SARS-CoV-2-specific T cell responses. In addition, we found alterations in follicular T helper (TFH) cell populations, such as enhanced TFH-TH2 following recovery from COVID-19. Our study revealed significant and long-term alterations in T cell populations and key events associated with COVID-19 pathogenesis.
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| 7. |
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| 8. |
- Hopkins, Francis, et al.
(författare)
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Pentameric C-reactive protein is a better prognostic biomarker and remains elevated for longer than monomeric CRP in hospitalized patients with COVID-19
- 2023
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Ingår i: Frontiers in Immunology. - : FRONTIERS MEDIA SA. - 1664-3224. ; 14
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Tidskriftsartikel (refereegranskat)abstract
- The differing roles of the pentameric (p) and monomeric (m) C-reactive protein (CRP) isoforms in viral diseases are not fully understood, which was apparent during the COVID-19 pandemic regarding the clinical course of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Herein, we investigated the predictive value of the pCRP and mCRP isoforms for COVID-19 severity in hospitalized patients and evaluated how the levels of the protein isoforms changed over time during and after acute illness. This study utilized samples from a well-characterized cohort of Swedish patients with SARS-CoV-2 infection, the majority of whom had known risk factors for severe COVID-19 and required hospitalization. The levels of pCRP were significantly raised in patients with severe COVID-19 and in contrast to mCRP the levels were significantly associated with disease severity. Additionally, the pCRP levels remained elevated for at least six weeks post inclusion, which was longer compared to the two weeks for mCRP. Our data indicates a low level of inflammation lasting for at least six weeks following COVID-19, which might indicate that the disease has an adverse effect on the immune system even after the viral infection is resolved. It is also clear that the current standard method of testing pCRP levels upon hospitalization is a useful marker for predicting disease severity and mCRP testing would not add any clinical relevance for patients with COVID-19.
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| 9. |
- Hopkins, Francis R., et al.
(författare)
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Major alterations to monocyte and dendritic cell subsets lasting more than 6 months after hospitalization for COVID-19
- 2023
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Ingår i: Frontiers in Immunology. - : Frontiers Media S.A.. - 1664-3224. ; 13
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Tidskriftsartikel (refereegranskat)abstract
- Introduction: After more than two years the Coronavirus disease-19 (COVID-19) pandemic continues to burden healthcare systems and economies worldwide, and it is evident that the effects on the immune system can persist for months post-infection. The activity of myeloid cells such as monocytes and dendritic cells (DC) is essential for correct mobilization of the innate and adaptive responses to a pathogen. Impaired levels and responses of monocytes and DC to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is likely to be a driving force behind the immune dysregulation that characterizes severe COVID-19.Methods: Here, we followed a cohort of COVID-19 patients hospitalized during the early waves of the pandemic for 6-7 months. The levels and phenotypes of circulating monocyte and DC subsets were assessed to determine both the early and long-term effects of the SARS-CoV-2 infection.Results: We found increased monocyte levels that persisted for 6-7 months, mostly attributed to elevated levels of classical monocytes. Myeloid derived suppressor cells were also elevated over this period. While most DC subsets recovered from an initial decrease, we found elevated levels of cDC2/cDC3 at the 6-7 month timepoint. Analysis of functional markers on monocytes and DC revealed sustained reduction in program death ligand 1 (PD-L1) expression but increased CD86 expression across almost all cell types examined. Finally, C-reactive protein (CRP) correlated positively to the levels of intermediate monocytes and negatively to the recovery of DC subsets.Conclusion: By exploring the myeloid compartments, we show here that alterations in the immune landscape remain more than 6 months after severe COVID-19, which could be indicative of ongoing healing and/or persistence of viral antigens.
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| 10. |
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| 11. |
- Sköldberg, Håkan, et al.
(författare)
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BIO-CCS I FJÄRRVÄRMESEKTORN – SYNTES
- 2022
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Den svenska fjärrvärmesektorn har stor potential att bidra med negativa koldioxidutsläpp genom bio-CCS, minst 10 Mton per år. Den största osäkerheten beträffande möjligheterna för bio-CCS gäller marknads förutsättningarna. Uppvärmningsbranschen har en vision om att år 2045 utgöra en kolsänka. Ett sätt att åstadkomma detta är genom att avskilja och lagra koldioxidutsläpp med biogent ursprung. Ett antal fjärrvärmeföretag har redan olika långt gångna planer på att satsa på bio-CCS. De har sett ett värde i att samarbeta kring hur detta kan åstadkommas. Ett led i detta är projektet Bio-CCS i fjärrvärmesektorn som består av ett gediget underlag baserat på forskning kring olika aspekter av frågan samt en strategi baserad på det underlaget. I denna rapport redovisas en syntes av detta forskningsarbete. Projektet visar att fjärrvärmesektorn har stor teoretisk potential att bidra med negativa koldioxidutsläpp, minst 10 Mton per år. I huvudsak är avskiljning, transport och lagring av koldioxid beprövad teknik även om tillämpningen i detta fall är ny. Även om bio-CCS är förknippad med energianvändning så bidrar tekniken sett ur ett systemperspektiv med stor nytta för att minska koldioxid[1]utsläppen. Bio-CCS är en relativt dyr teknik och det är angeläget att utnyttja samverkan och kluster för att exempelvis skapa ökad kostnadseffektivitet i transport och mellanlagring. Tillgång till lagringsplatser är en förutsättning för framgång och flera alternativ bedöms bli tillgängliga. Det kan dock uppstå konkurrens om tillgången till lagringsplatserna. De regelmässiga förutsättningarna för bio-CCS i Sverige har förbättrats avsevärt de senaste dryga decenniet. Flera regelmässiga hinder kvarstår dock. En del utgör mindre barriärer, andra är av mer betydande karaktär. Den största osäkerheten beträffande möjligheterna för bio-CCS gäller ekonomin. Flera potentiella finansieringsmetoder har studerats, både stöd, regleringar och frivilligmarknader. Det finns fortfarande oklarheter kring syftet med planerade stöd och det framtida ägandet av de negativa utsläppen. Det genomförda projektet har skapat ett forum för kunskapsuppbyggnad, erfarenhetsutbyte och nätverkande, vilket de deltagande företagen bedömt vara mycket värdefullt.
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| 12. |
- Svanberg, Cecilia, et al.
(författare)
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Complement-Opsonized HIV Modulates Pathways Involved in Infection of Cervical Mucosal Tissues : A Transcriptomic and Proteomic Study
- 2021
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Ingår i: Frontiers in Immunology. - : FRONTIERS MEDIA SA. - 1664-3224. ; 12
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Tidskriftsartikel (refereegranskat)abstract
- Genital mucosal transmission is the most common route of HIV spread. The initial responses triggered at the site of viral entry are reportedly affected by host factors, especially complement components present at the site, and this will have profound consequences on the outcome and pathogenesis of HIV infection. We studied the initial events associated with host-pathogen interactions by exposing cervical biopsies to free or complement-opsonized HIV. Opsonization resulted in higher rates of HIV acquisition/infection in mucosal tissues and emigrating dendritic cells. Transcriptomic and proteomic data showed a significantly more pathways and higher expression of genes and proteins associated with viral replication and pathways involved in different aspects of viral infection including interferon signaling, cytokine profile and dendritic cell maturation for the opsonized HIV. Moreover, the proteomics data indicate a general suppression by the HIV exposure. This clearly suggests that HIV opsonization alters the initial signaling pathways in the cervical mucosa in a manner that promotes viral establishment and infection. Our findings provide a foundation for further studies of the role these early HIV induced events play in HIV pathogenesis.
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| 13. |
- Svanberg, Cecilia, et al.
(författare)
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Conformational state of C-reactive protein is critical for reducing immune complex-triggered type I interferon response: Implications for pathogenic mechanisms in autoimmune diseases imprinted by type I interferon gene dysregulation
- 2023
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Ingår i: Journal of Autoimmunity. - : ACADEMIC PRESS LTD- ELSEVIER SCIENCE LTD. - 0896-8411 .- 1095-9157. ; 135
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Tidskriftsartikel (refereegranskat)abstract
- Presence of autoantibodies targeting nuclear constituents, i.e., double-stranded DNA and small nuclear ribonu-cleoproteins (snRNPs), remain a cornerstone in systemic lupus erythematosus (SLE). Fc gamma receptor IIa (Fc gamma RIIa) dependent uptake of nucleic acid containing immune complexes (ICs) by plasmacytoid dendritic cells (PDCs) can activate toll-like receptors (TLRs) such as TLR7 and TLR9 resulting in type I interferon (IFN) production. Pre-viously, the classical liver-derived acute-phase reactant C-reactive protein (CRP) has been suggested to reduce IC -induced type I IFN production, whereas monomeric (mCRP) vs. pentameric (pCRP) mediated effects have not yet been unraveled. Herein, peripheral blood mononuclear cells (PBMCs) or enriched blood DCs from healthy vol-unteers were stimulated with SLE sera, snRNP-IgG (ICs), or TLR ligands with or without pCRP, mCRP, or anti- Fc gamma RIIa antibody. Type I IFNs and cytokine responses were investigated using quantitative PCR, ELISA, and flow cytometry. pCRP inhibited IFN gene expression in PBMCs and enriched DCs after incubation with ICs, compared to ICs alone, whereas mCRP had significantly less inhibitory effect. The effect was independent on the order in which IC or CRP was added to the cells. In addition, pCRP inhibited IFN induced by other TLR stimulators, implicating broader inhibitory effects induced by pCRP. We demonstrate pronounced immunoregulatory functions of CRP whereas the inhibitory properties were evidently dependent on CRPs intact conformational state. The inhibition of type I IFNs was not due to competition of Fc gamma Rs, or binding of CRP to the ICs. Our findings have implications for autoimmune IC-mediated conditions imprinted by type I IFN gene dysregulation.
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| 14. |
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| 15. |
- Svanberg, Cecilia, 1991-
(författare)
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HIV-1 Exploitation of Dendritic Cell Functionality and Initial Responses in Mucosal Tissues : Elucidation of Influence of HIV-1 Complement Opsonization, and HIV-1-HSV-2 Co-infection
- 2023
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Human immunodeficiency virus (HIV)-1 is transmitted between individuals via sexual intercourse or via blood products. To date there are 38 million people living with chronic HIV infection and around 1.5 million yearly acquire a new infection. HIV is known to have detrimental effects on the immune system and its cell function and leads to the development of acquired immune deficiency syndrome (AIDS). AIDS is characterized by opportunistic infections often fatal to the individual. Mucosal tissues, which are the main site of HIV-1 infection, consist of a complex network of different cell types building up a barrier against the outside world. In the mucosa there are multiple immune cells and one of them is the dendritic cells (DCs), a professional antigen presenting cell needed for priming of adaptive T cell responses. DCs are rarely productively infected with HIV-1 but the virus can modulate the DC phenotype and function by mere exposure to the virus. There are many factors that influence viral transmission including prevalent inflammatory conditions or infections in the genital tract. For instance, a newly acquired herpes simplex virus-2 (HSV-2) infection increases the risk of transmission at HIV-1 exposure by four times. A vital part of the innate immune defense is the complement system, which consists of proteins found in all body fluids. Normally during complement activation, it leads to lysis of pathogens, but HIV-1 can evade this process. This is achieved by the incorporated complement regulatory proteins in the viral plasma membrane leading to accumulation of opsonizing complement fragments on the HIV-1 particles. Our aim with these studies was to deepen the understanding of the HIV-1 exploitation of DC function and elucidate the initial effects exposure and establishment of HIV-1 infection has on the mucosal tissues and immune cells. In addition, we aimed to elucidate the effects HSV-2 exerts on the HIV-1-infection of DCs and how viral complement opsonization affects the viral infection and activation of immune responses. In Paper I we found that coinfection of monocyte derived DCs (MDDCs) with HIV-1 and HSV-2 decreases the amount of the HIV-1 restriction factors SAMHD1 and TREX1 in MDDCs, leading to increased productive HIV-1 infection. In Paper II and III we found that HIV-1 utilizes the complement system to induce higher productive infection of the colorectal and cervical mucosal DCs. The different forms of HIV, free or complement opsonized, had distinct effects on the immune responses and T cell phenotypes in the tissues, all in favor of HIV-1 establishment and productive infection. In Paper IV, HIV-1 exposed DCs triggered after crosstalk with suppressive T cells a prolonged type I interferon response and an upregulation of coinhibitory molecules on the DCs. The findings in this thesis add to the knowledge of HIV-1 early transmission events, how co-infection modulates DC function, and how the presence of HIV-1 affects the priming of adaptive immune responses.
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| 16. |
- Svanberg, Cecilia, et al.
(författare)
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HIV-1 induction of tolerogenic dendritic cells is mediated by cellular interaction with suppressive T cells
- 2022
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Ingår i: Frontiers in Immunology. - : Frontiers Media SA. - 1664-3224. ; 13
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Tidskriftsartikel (refereegranskat)abstract
- HIV-1 infection gives rise to a multi-layered immune impairment in most infected individuals. The chronic presence of HIV-1 during the priming and activation of T cells by dendritic cells (DCs) promotes the expansion of suppressive T cells in a contact-dependent manner. The mechanism behind the T cell side of this HIV-induced impairment is well studied, whereas little is known about the reverse effects exerted on the DCs. Herein we assessed the phenotype and transcriptome profile of mature DCs that have been in contact with suppressive T cells. The HIV exposed DCs from cocultures between DCs and T cells resulted in a more tolerogenic phenotype with increased expression of e.g., PDL1, Gal-9, HVEM, and B7H3, mediated by interaction with T cells. Transcriptomic analysis of the DCs separated from the DC-T cell coculture revealed a type I IFN response profile as well as an activation of pathways involved in T cell exhaustion. Taken together, our data indicate that the prolonged and strong type I IFN signaling in DCs, induced by the presence of HIV during DC-T cell cross talk, could play an important role in the induction of tolerogenic DCs and suppressed immune responses seen in HIV-1 infected individuals.
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| 17. |
- Svanberg, Sune, et al.
(författare)
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Applications of terawatt lasers
- 1994
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Ingår i: LASER SPECTROSCOPY - XITH INTERNATIONAL CONFERENCE. - : AIP. - 1551-7616 .- 0094-243X. - 1563962624 ; :290, s. 264-269
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Konferensbidrag (refereegranskat)
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| 18. |
- Svelander, Cecilia, 1980, et al.
(författare)
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Processing of tomato: Impact on in vitro bioaccessibility of lycopene and textural properties
- 2010
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Ingår i: Journal of the Science of Food and Agriculture. - : Wiley. - 1097-0010 .- 0022-5142. ; 90:10, s. 1665-1672
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Human studies have demonstrated that processing of tomato can greatly increase lycopene bioavailability. However, the difference between processing methods is not widely investigated. In the current study different thermal treatments of tomato were evaluated with regard to their impact on in vitro bioaccessibility and retention of lycopene and β-carotene as well as textural properties. Thermal treatments used were low (60°C) and high (90°C) temperature blanching followed by boiling. RESULTS: Lycopene was relatively stable during thermal treatment, whereas β-carotene was significantly (P
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| 19. |
- Zaini, Ilman Nuran, et al.
(författare)
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A pilot-scale test of plasma torch application for decarbonising the steel reheating furnaces
- 2023
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Ingår i: THERMAL SCIENCE AND ENGINEERING PROGRESS. - : Elsevier BV. - 2451-9049. ; 40
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Tidskriftsartikel (refereegranskat)abstract
- The decarbonisation of the Swedish iron and steel industry is crucial in achieving Sweden's target to achieve zero net emissions of greenhouse gases (GHG) by 2045. Direct electrification of industrial furnaces could be an important milestone in decarbonising the iron and steel plants. In this study, pilot-scale trials were performed to investigate the possibility of plasma torch application for steel reheating furnaces. A 250 kW DC plasma torch was used to heat the furnace from room to the operating temperature of 1200 degrees C. Different plasma carrier gases were then used to study their impact on the plasma torch efficiency, furnace temperature profile, NOX emission, and steel oxidation. The results show that the furnace could be heated at a relatively uniform temperature and reasonable time. The combination of air and LPG in the plasma generator provides the most uniform temperature distribution and highest plasma torch efficiency, but it generates the highest NOX emission. N2 as plasma gas resulted in notably poorer temperature distribution and lower plasma torch efficiency; however, it can suppress the oxide formations. Meanwhile, CO2 as plasma gas could be a promising option among the studied gas mixtures as it can provide a good heating performance with a low NOX formation. In summary, the current study has proved that it is practical and functionally possible to heat steel using plasma technology.
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