Pathogenesis of macrophage activation syndrome and potential for cytokine- directed therapies

The Scutellaria-Coptis herb couple and its active small-molecule ingredient wogonoside alleviate cytokine storm by regulating the CD39/NLRP3/GSDMD signaling pathway

ETHNOPHARMACOLOGICAL RELEVANCE

A drug pair is a fundamental aspect of traditional Chinese medicine prescriptions. Scutellaria baicalensis Georgi and Coptis chinensis Franch, commonly used as an herb couple (SBCC), are representative heat-clearing and dampness-drying drugs. They possess functions such as clearing heat, drying dampness, purging fire, and detoxifying. These herbs are used in both traditional and modern medicine for treating inflammation.

AIM OF THE STUDY

This study investigated the effects of SBCC on cytokine storm syndrome (CSS) and explored its potential regulatory mechanism.

MATERIALS AND METHODS

We assessed the impact of SBCC in a sepsis-induced acute lung injury mouse model by administering an intraperitoneal injection of LPS (15 mg/kg). The cytokine levels in the serum and lungs, the wet-to-dry ratio of the lungs, and lung histopathological changes were evaluated. The macrophages in the lung tissue were examined through transmission electron microscopy. Western blot was used to measure the levels of the CD39/NLRP3/GSDMD pathway-related proteins. Immunofluorescence imaging was used to assess the activation of pro-caspase-1 and ASC and their interaction. AMP-Glo™ assay was used to screen for active ingredients in SBCC targeting CD39. One of the ingredients was selected, and its effect on cell viability was assessed. We induced inflammation in macrophages using LPS + ATP and detected the levels of proinflammatory factors. The images of cell membrane large pores were captured using scanning electron microscopy, the interaction between NLRP3 and ASC was detected using immunofluorescence imaging, and the levels of CD39/NLRP3/GSDMD pathway-related proteins were assessed using Western blot.

RESULTS

SBCC administration effectively mitigated LPS-induced cytokine storm, pulmonary edema and lung injury. Furthermore, it repressed the programmed death of lung tissue macrophages by inhibiting the NLRP3/GSDMD pyroptosis pathway and regulating the CD39 purinergic pathway. Based on the results of the AMP-Glo™ assay, we selected wogonoside for further valuation. Wogonoside alleviated LPS + ATP-induced inflammatory damage by regulating the inhibiting the NLRP3/GSDMD pyroptosis pathway and regulating the CD39 purinergic pathway. However, its effect on NLRP3 is not mediated though CD39.

CONCLUSION

SBCC and its active small-molecule ingredient, wogonoside, improved CSS by regulating the NLRP3/GSDMD pyroptosis pathway and its upstream CD39 purinergic pathway. It is essential to note that the regulatory effect of wogonoside on NLRP3 is not mediated by CD39.

α2-Antiplasmin is associated with macrophage activation and fibrin deposition in a macrophage activation syndrome mouse model

Macrophage activation syndrome (MAS) is a life-threatening condition, characterized by cytopenia, multi-organ dysfunction, and coagulopathy associated with excessive activation of macrophages. In this study, we investigated the roles of alpha2-antiplasmin (α2AP) in the progression of MAS using fulminant MAS mouse model induced by toll-like receptor-9 agonist (CpG) and D-(+)-galactosamine hydrochloride (DG). α2AP deficiency attenuated macrophage accumulation, liver injury, and fibrin deposition in the MAS model mice. Interferon-γ (IFN-γ) is associated with macrophage activation, including migration, and plays a pivotal role in MAS progression. α2AP enhanced the IFN-γ-induced migration, and tissue factor production. Additionally, we showed that fibrin-induced macrophage activation and tumor necrosis factor-α production. Moreover, the blockade of α2AP by neutralizing antibodies attenuated macrophage accumulation, liver injury, and fibrin deposition in the MAS model mice. These data suggest that α2AP may regulate IFN-γ-induced responses and be associated with macrophage activation and fibrin deposition in the MAS progression.

New discoveries in the genetics and genomics of systemic juvenile idiopathic arthritis

INTRODUCTION

Systemic juvenile idiopathic arthritis (sJIA) is a severe inflammatory condition with onset in childhood. It is sporadic, but elements of its stereotypical innate immune responses are likely genetically encoded by both common variants with small effect sizes and rare variants with larger effects.

AREAS COVERED

Genomic investigations have defined the unique genetic architecture of sJIA. Identification of the class II HLA locus as the strongest sJIA risk factor for the first time brought attention to T lymphocytes and adaptive immune mechanisms in sJIA. The importance of the human leukocyte antigen (HLA) locus was reinforced by recognition that HLA-DRB1*15 alleles are strongly associated with development of drug reactions and sJIA-associated lung disease (sJIA-LD). At the IL1RN locus, genetic variation relates to both risk of sJIA and may also predict non-response to anakinra. Finally, rare genetic variants may have critical roles in disease complications, such as homozygous LACC1 mutations in families with an sJIA-like illness, and hemophagocytic lymphohistiocytosis (HLH) gene variants in some children with macrophage activation syndrome (MAS).

EXPERT OPINION

Genetic and genomic analysis of sJIA holds great promise for both basic discovery of the course and complications of sJIA, and may help guide personalized medicine and therapeutic decision-making.

PD-L1/PD-1 pathway: a potential neuroimmune target for pain relief

Pain is a common symptom of many diseases with a high incidence rate. Clinically, drug treatment, as the main method to relieve pain at present, is often accompanied by different degrees of adverse reactions. Therefore, it is urgent to gain a profound understanding of the pain mechanisms in order to develop advantageous analgesic targets. The PD-L1/PD-1 pathway, an important inhibitory molecule in the immune system, has taken part in regulating neuroinflammation and immune response. Accumulating evidence indicates that the PD-L1/PD-1 pathway is aberrantly activated in various pain models. And blocking PD-L1/PD-1 pathway will aggravate pain behaviors. This review aims to summarize the emerging evidence on the role of the PD-L1/PD-1 pathway in alleviating pain and provide an overview of the mechanisms involved in pain resolution, including the regulation of macrophages, microglia, T cells, as well as nociceptor neurons. However, its underlying mechanism still needs to be further elucidated in the future. In conclusion, despite more deep researches are needed, these pioneering studies indicate that PD-L1/PD-1 may be a potential neuroimmune target for pain relief.

Systemic juvenile idiopathic arthritis-associated lung disease: A retrospective cohort study

BACKGROUND

Lung damage in systemic juvenile arthritis (sJIA) is one of the contemporary topics in pediatric rheumatology. Several previous studies showed the severe course and fatal outcomes in some patients. The information about interstitial lung disease (ILD) in the sJIA is scarce and limited to a total of 100 cases.

AIM

To describe the features of sJIA patients with ILD in detail.

METHODS

In the present retrospective cohort study, information about 5 patients less than 18-years-old with sJIA and ILD were included. The diagnosis of sJIA was made according to the current 2004 and new provisional International League of Associations for Rheumatology criteria 2019. ILD was diagnosed with chest computed tomography with the exclusion of other possible reasons for concurrent lung involvement. Macrophage activation syndrome (MAS) was diagnosed with HLH-2004 and 2016 EULAR/ACR/PRINTO Classification Criteria and hScores were calculated during the lung involvement.

RESULTS

The onset age of sJIA ranged from 1 year to 10 years. The time interval before ILD ranged from 1 mo to 3 years. The disease course was characterized by the prevalence of the systemic features above articular involvement, intensive rash (100%), persistent and very active MAS (hScore range: 194-220) with transaminitis (100%), and respiratory symptoms (100%). Only 3 patients (60%) developed a clubbing phenomenon. All patients (100%) had pleural effusion and 4 patients (80%) had pericardial effusion at the disease onset. Two patients (40%) developed pulmonary arterial hypertension. Infusion-related reactions to tocilizumab were observed in 3 (60%) of the patients. One patient with trisomy 21 had a fatal disease course. Half of the remaining patients had sJIA remission and 2 patients had improvement. Lung disease improved in 3 patients (75%), but 1 of them had initial deterioration of lung involvement. One patient who has not achieved the sJIA remission had the progressed course of ILD. No cases of hyper-eosinophilia were noted. Four patients (80%) received canakinumab and one (20%) tocilizumab at the last follow-up visit.

CONCLUSION

ILD is a severe life-threatening complication of sJIA that may affect children of different ages with different time intervals since the disease onset. Extensive rash, serositis (especially pleuritis), full-blown MAS with transaminitis, lymphopenia, trisomy 21, eosinophilia, and biologic infusion reaction are the main predictors of ILD. The following studies are needed to find the predictors, pathogenesis, and treatment options, for preventing and treating the ILD in sJIA patients.

[Combined immunosuppression with cyclosporin A, mycophenolate mofetil (MMF) and dexamethasone for activity control of recurrent secondary hemophagocytic lymphohistiocytosis (sHLH) with underlying systemic lupus erythematosus (SLE)]

A 42-year-old female patient was admitted to hospital due to acute neurological symptoms (dysarthria, disorientation). After exclusion of cerebral ischemia and hemorrhage an autoimmune encephalitis was diagnosed. Shortly before as an outpatient the suspicion of the presence of systemic lupus erythematosus (SLE) was voiced. The patient showed a constellation of high levels of inflammatory laboratory parameters and within a few days developed a severe pancytopenia. In the presence of all diagnostic criteria a secondary hemophagocytic lymphohistiocytosis (sHLH) was diagnosed and confirmed by a kidney biopsy during the course of the underlying SLE. The immunosuppressive treatment with etoposide and high-dose dexamethasone according to the HLH-94 protocol only showed temporary success. After 3 weeks of treatment with a protocol-conform dose reduction, under running treatment a new exacerbation of symptoms was confirmed. A renewed dose escalation of the drugs used did not lead to control of the symptoms. The inflammatory activity could only be sustainably controlled by the use of cyclosporin A in combination with mycophenolate mofetil (MMF) and dexamethasone. After stabilization of the condition of the patient, an outpatient follow-up care was possible.

Leucine alleviates cytokine storm syndrome by regulating macrophage polarization via the mTORC1/LXRα signaling pathway

Cytokine storms are associated with severe pathological damage and death in some diseases. Excessive activation of M1 macrophages and the subsequent secretion of pro-inflammatory cytokines are a major cause of cytokine storms. Therefore, promoting the polarization of M2 macrophages to restore immune balance is a promising therapeutic strategy for treating cytokine storm syndrome (CSS). This study was aimed at investigating the potential protective effects of leucine on lipopolysaccharide (LPS)-induced CSS in mice and exploring the underlying mechanisms. CSS was induced by LPS administration in mice, which were concurrently administered leucine orally. In vitro, bone marrow derived macrophages (BMDMs) were polarized to M1 and M2 phenotypes with LPS and interleukin-4 (IL-4), respectively, and treated with leucine. Leucine decreased mortality in mice treated with lethal doses of LPS. Specifically, leucine decreased M1 polarization and promoted M2 polarization, thus diminishing pro-inflammatory cytokine levels and ameliorating CSS in mice. Further studies revealed that leucine-induced macrophage polarization through the mechanistic target of rapamycin complex 1 (mTORC1)/liver X receptor α (LXRα) pathway, which synergistically enhanced the expression of the IL-4-induced M2 marker Arg1 and subsequent M2 polarization. In summary, this study revealed that leucine ameliorates CSS in LPS mice by promoting M2 polarization through the mTORC1/LXRα/Arg1 signaling pathway. Our findings indicate that a fundamental link between metabolism and immunity contributes to the resolution of inflammation and the repair of damaged tissues.

Prognostic factors in patients with secondary hemophagocytic lymphohistioc ytosis in a Chinese cohort

Hemophagocytic lymphohistiocytosis (HLH) is a rare hyperinflammatory syndrome with high mortality mediated by an unbridled and persistent activation of cytotoxic T lymphocytes and natural killer cells. However, the influence factors of early death in adult sHLH patients are still not fully elucidated, which need further investigating. We have conducted an observational study of adult HLH patients between January 2016 and December 2022. All patients are enrolled according to HLH-2004 criteria. Clinical manifestations, laboratory data, treatments, and outcomes have been recorded. Influence factors associated with prognosis are calculated by using logistic regression models. Overall, 220 patients enrolled in this study. The etiologies of HLH were divided into five groups including autoimmune-associated hemophagocytic syndrome (AAHS) (n = 90, 40.9%), malignancies (n = 73, 33.2%), EBV-HLH (n = 18, 8.2%), infection excluded EBV (n = 24, 10.9%), and other triggers (n = 15, 6.8%). Among them, EBV-HLH had the highest mortality (77.8%), and AAHS had the lowest mortality (14.4%). Multivariate analysis indicated that age (≥ 38 years old), cytopenia ≥ 2 lines, platelets (≤ 50 × 109/L), aspartate aminotransferase (≥ 135U/L), prothrombin time (≥ 14.9 s) and activated partial thromboplastin time (≥ 38.5s), EBV, and fungal infection are independent risk factors for poor prognosis of HLH. Adult HLH patients with elder age, cytopenia ≥ 2 lines, levels of decreased platelets, increased AST, prolonged PT and APTT, EBV, and fungal infection tend to have a poor prognosis.

Disease Course, Treatments, and Outcomes of Children With Systemic Juvenile Idiopathic Arthritis-Associated Lung Disease

OBJECTIVE

Systemic juvenile idiopathic arthritis-associated lung disease (SJIA-LD) is a life-threatening disease complication. Key questions remain regarding clinical course and optimal treatment approaches. The objectives of the study were to detail management strategies after SJIA-LD detection, characterize overall disease courses, and measure long-term outcomes.

METHODS

This was a prospective cohort study. Clinical data were abstracted from the electronic medical record, including current clinical status and changes since diagnosis. Serum biomarkers were determined and correlated with presence of LD.

RESULTS

We enrolled 41 patients with SJIA-LD, 85% with at least one episode of macrophage activation syndrome and 41% with adverse reactions to a biologic. Although 93% of patients were alive at last follow-up (median 2.9 years), 37% progressed to requiring chronic oxygen or other ventilator support, and 65% of patients had abnormal overnight oximetry studies, which changed over time. Eighty-four percent of patients carried the HLA-DRB1*15 haplotype, significantly more than patients without LD. Patients with SJIA-LD also showed markedly elevated serum interleukin-18 (IL-18), variable C-X-C motif chemokine ligand 9 (CXCL9), and significantly elevated matrix metalloproteinase 7. Treatment strategies showed variable use of anti-IL-1/6 biologics and addition of other immunomodulatory treatments and lung-directed therapies. We found a broad range of current clinical status independent of time from diagnosis or continued biologic treatment. Multidomain measures of change showed imaging features were the least likely to improve with time.

CONCLUSION

Patients with SJIA-LD had highly varied courses, with lower mortality than previously reported but frequent hypoxia and requirement for respiratory support. Treatment strategies were highly varied, highlighting an urgent need for focused clinical trials.

Improved survival in COVID-19 related sepsis and ARDS treated with a unique "triple therapy" including therapeutic plasma exchange: A single center retrospective analysis

BACKGROUND

Throughout the COVID-19 pandemic, the mortality of critically ill patients remained high. Our group developed a treatment regimen targeting sepsis and ARDS which we labeled "triple therapy" consisting of (1) corticosteroids, (2) therapeutic plasma exchange (TPE), and (3) timely intubation with lung protective ventilation. Our propensity analysis assesses the impact of triple therapy on survival in COVID-19 patients with sepsis and ARDS.

METHODS

Retrospective propensity analysis comparing triple therapy to no triple therapy in adult critically ill COVID-19 patients admitted to the Intensive Care Unit at Lexington Medical Center from 1 March 2020 through 31 October 2021.

RESULTS

Eight hundred and fifty-one patients were admitted with COVID-19 and 53 clinical and laboratory variables were analyzed. Multivariable analysis revealed that triple therapy was associated with increased survival (OR: 1.91; P = .008). Two propensity score-adjusted models demonstrated an increased likelihood of survival in patients receiving triple therapy. Patients with thrombocytopenia were among those most likely to experience increased survival if they received early triple therapy. Decreased survival was observed with endotracheal intubation ≥7 days from hospital admission (P < .001) and there was a trend toward decreased survival if TPE was initiated ≥6 days from hospital admission (P = .091).

CONCLUSION

Our analysis shows that early triple therapy, defined as high-dose methylprednisolone, TPE, and timely invasive mechanical ventilation within the first 96 hours of admission, may improve survival in critically ill septic patients with ARDS secondary to COVID-19 infection. Further studies are needed to define specific phenotypes and characteristics that will identify those patients most likely to benefit.

Adjunctive use of oral MAF is associated with no disease progression or mortality in hospitalized patients with COVID-19 pneumonia: The single-arm COral-MAF1 prospective trial

Based on a growing body of evidence that a dysregulated innate immune response mediated by monocytes/macrophages plays a key role in the pathogenesis of COVID-19, a clinical trial was conducted to investigate the therapeutic potential and safety of oral macrophage activating factor (MAF) plus standard of care (SoC) in the treatment of hospitalized patients with COVID-19 pneumonia. Ninety-seven hospitalized patients with confirmed COVID-19 pneumonia were treated with oral MAF and a vitamin D3 supplement, in combination with SoC, in a single-arm, open label, multicentre, phase II clinical trial. The primary outcome measure was a reduction in an intensive care unit transfer rate below 13% after MAF administration. At the end of the study, an additional propensity score matching (PSM) analysis was performed to compare the MAF group with a control group treated with SoC alone. Out of 97 patients treated with MAF, none needed care in the ICU and/or intubation with mechanical ventilation or died during hospitalization. Oxygen therapy was discontinued after a median of nine days of MAF treatment. The median length of viral shedding and hospital stay was 14 days and 18 days, respectively. After PSM, statistically significant differences were found in all of the in-hospital outcomes between the two groups. No mild to serious adverse events were recorded during the study. Notwithstanding the limitations of a single-arm study, which prevented definitive conclusions, a 21-day course of MAF treatment plus SoC was found to be safe and promising in the treatment of hospitalized adult patients with COVID-19 pneumonia. Further research will be needed to confirm these preliminary findings.

The nuclear cytokine IL-37a controls lethal cytokine storms primarily via IL-1R8-independent transcriptional upregulation of PPARγ

Cytokine storms are crucial in the development of various inflammatory diseases, including sepsis and autoimmune disorders. The immunosuppressive cytokine INTERLEUKIN (IL)-37 consists of five isoforms (IL-37a-e). We identified IL-37a as a nuclear cytokine for the first time. Compared to IL-37b, IL-37a demonstrated greater efficacy in protecting against Toll-like receptor-induced cytokine hypersecretion and lethal endotoxic shock. The full-length (FL) form of IL-37a and the N-terminal fragment, which is processed by elastase, could translocate into cell nuclei through a distinctive nuclear localization sequence (NLS)/importin nuclear transport pathway. These forms exerted their regulatory effects independent of the IL-1R8 receptor by transcriptionally upregulating the nuclear receptor peroxisome proliferator-activated receptor (PPARγ). This process involved the recruitment of the H3K4 methyltransferase complex WDR5/MLL4/C/EBPβ and H3K4me1/2 to the enhancer/promoter of Pparg. The receptor-independent regulatory pathway of the nuclear IL-37a-PPARγ axis and receptor-dependent signaling by secreted IL-37a maintain homeostasis and are potential therapeutic targets for various inflammatory diseases, including sepsis.

Opportunities and challenges in the diagnostic utility of dermal interstitial fluid

The volume of interstitial fluid (ISF) in the human body is three times that of blood. Yet, collecting diagnostically useful ISF is more challenging than collecting blood because the extraction of dermal ISF disrupts the delicate balance of pressure between ISF, blood and lymph, and because the triggered local inflammation further skews the concentrations of many analytes in the extracted fluid. In this Perspective, we overview the most meaningful differences in the make-up of ISF and blood, and discuss why ISF cannot be viewed generally as a diagnostically useful proxy for blood. We also argue that continuous sensing of small-molecule analytes in dermal ISF via rapid assays compatible with nanolitre sample volumes or via miniaturized sensors inserted into the dermis can offer clinically advantageous utility, particularly for the monitoring of therapeutic drugs and of the status of the immune system.

Population-level single-cell genomics reveals conserved gene programs in systemic juvenile idiopathic arthritis

Systemic autoimmune and autoinflammatory diseases are characterized by genetic and cellular heterogeneity. While current single-cell genomics methods provide insights into known disease subtypes, these analysis methods do not readily reveal novel cell-type perturbation programs shared among distinct patient subsets. Here, we performed single-cell RNA-Seq of PBMCs of patients with systemic juvenile idiopathic arthritis (SJIA) with diverse clinical manifestations, including macrophage activation syndrome (MAS) and lung disease (LD). We introduced two new computational frameworks called UDON and SATAY-UDON, which define patient subtypes based on their underlying disrupted cellular programs as well as associated biomarkers or clinical features. Among twelve independently identified subtypes, this analysis uncovered what we believe to be a novel complement and interferon activation program identified in SJIA-LD monocytes. Extending these analyses to adult and pediatric lupus patients found new but also shared disease programs with SJIA, including interferon and complement activation. Finally, supervised comparison of these programs in a compiled single-cell pan-immune atlas of over 1,000 healthy donors found a handful of normal healthy donors with evidence of early inflammatory activation in subsets of monocytes and platelets, nominating possible biomarkers for early disease detection. Thus, integrative pan-immune single-cell analysis resolved what we believe to be new conserved gene programs underlying inflammatory disease pathogenesis and associated complications.

A distinct cytokine network distinguishes chimeric antigen receptor T cell (CAR-T)-associated hemophagocytic lymphohistiocytosis-like toxicity (carHLH) from severe cytokine release syndrome following CAR-T therapy

BACKGROUND AIMS

With the increasing application of chimeric antigen receptor (CAR)-T cell therapy in various malignancies, an extra toxicity profile has been revealed, including a severe complication resembling hemophagocytic lymphohistiocytosis (HLH), which is usually disguised by severe cytokine release syndrome (CRS).

METHODS

In a clinical trial in whom 99 patients received B-cell maturation antigen CAR-T cells, we identified 20 (20.20%) cases of CAR-T cell-associated HLH (carHLH), most of whom possessed a background of severe CRS (grade ≥3). The overlapping features of carHLH and severe CRS attracted us to further explore the differences between them.

RESULTS

We showed that carHLH can be distinguished by extreme elevation of interferon-γ, granzyme B, interleukin-1RA and interleukin-10, which can be informative in developing prevention and management strategies of this toxicity. Moreover, we developed a predictive model of carHLH with a mean area under the curve of 0.81 ± 0.07, incorporating serum lactate dehydrogenase at day 6 post-CRS and serum fibrinogen at day 3 post-CRS.

CONCLUSIONS

The incidence of carHLH in CAR-T recipients might be relatively higher than we previously thought. relatively higher than we previously. A cytokine network distinguished from CRS is responsible for carHLH. And corresponding cytokine-directed therapies, especially targeting IL-10, are worth trying.

Successful use of subcutaneous anakinra in hemophagocytic lymphohistiocytosis precipitated by candidiasis in a patient with systemic lupus erythematosus: A case report and description of a novel therapeutic regimen

Hemophagocytic lymphohistiocytosis (HLH) is a rare and often fatal condition characterized by inappropriate immune system activation leading to a "cytokine storm", and ultimately resulting in end-organ damage. Causes include primary defects in genes involved in immune-mediated cytolytic pathways, or secondary triggers such as infection or malignancy. We describe a case of HLH precipitated by fungal infection which occurred as a consequence of immunosuppression for management of systemic lupus erythematosus (SLE) and necrotizing myopathy. The patient presented with immune-mediated disease of the muscles and lung which was treated with high-dose corticosteroids and aggressive immunosuppression. HLH emerged in the context of confirmed candidiasis and features of severe sepsis. The patient responded rapidly to antifungal therapy and high-dose anakinra, which was administered subcutaneously and progressively weaned over 4 weeks. She completed HLH treatment as an outpatient and remains well at 12 months with controlled SLE and no recurrence of HLH.

Adult-onset Still's disease complicated by macrophage activation syndrome during pregnancy: a case-based review

Adult-onset Still's disease is a rare, systemic inflammatory rheumatic disease characterized by recurrent fevers, arthritis, and an evanescent rash. One of the most serious hematologic derangements that can be seen with adult-onset Still's disease is macrophage activation syndrome. Macrophage activation syndrome is characterized by activation of lymphocytes, resulting in a cytokine storm and hemophagocytosis in the bone marrow, along with multi-organ failure. Adult-onset Still's disease with macrophage activation syndrome first presenting during pregnancy is exceptionally rare; here, we report two unique cases of such a presentation and review the pertinent literature. Both of our cases presented critically ill with end-organ failure, and responded to immunosuppression; fetal demise was present in one and an emergency caesarean section with a viable fetus was performed in the other patient. Maternal outcomes were favorable in both cases and both patients did well long-term with systemic therapy. Systemic immunosuppression, particularly anti-IL1 therapy, may be considered as treatment for this rare and life-threatening condition when presenting during pregnancy.

Panniculitic primary cutaneous gamma delta T-cell lymphoma with concomitant features of autoimmune disease emphasizing a pathophysiologic continuum of lupus profundus with the panniculitic T cell lymphomas

Certain T-cell lymphomas exhibit unique homing properties of the neoplastic lymphocytes for the subcutaneous fat. There are two primary forms of subcutaneous panniculitic lymphomas of T-cell origin. One falls under the designation of primary cutaneous gamma-delta T-cell lymphomas (PGD-TCL) whereby there is dominant involvement of the fat defininng a panniculitic form of PGD-TCL. The neoplastic cells are of the gamma-delta subset and are either double negative for CD4 and CD8 and/or can express CD8. They often have an aggressive clinical course. The other form of panniculitic T-cell lymphoma falls under the designation of subcutaneous panniculitis-like T-cell lymphoma (SPTCL). It represents a subcutaneous lymphoma derived from CD8+ T cells of the alpha-beta subset and typically has an indolent course. These two forms of panniculitic T-cell lymphoma exhibit overlapping histologic features with lupus profundus (LP), a putative form of panniculitic T-cell dyscrasia. We present three cases of PGD-TCL of the fat in the setting of lupus erythematosus (LE) (two cases) and dermatomyositis (DM) (one case), respectively. There were concurrent features of LE and DM in their lymphoma biopsies in two cases while a prior biopsy in one was interpreted as LP. In this latter case, the LP diagnosis presaged the diagnosis of panniculitic PGD-TCL by three years. One patient diagnosed with panniculitic PGD-TCL had hemophagocytic syndrome after developing a lupus-like complex including certain supportive serologies such as antibodies to double-stranded DNA following initiation of statin therapy. The second patient presented with PGD-TCL and concomitant features of anti-nuclear matrix 2 (NXP2) DM. The third patient presented in 2003 with LP and overlying skin features of acute LE, initially responding to Plaquenil, and then four years later was diagnosed with PGD-TCL heralded by Plaquenil treatment resistance. Two of the patients died of their lymphoma. All biopsies showed a characteristic histopathology of PGD-TCL. In two cases, the PGD-TCL was associated with overlying LE-cutaneous findings; another case had skin changes of lymphocyte-rich DM. In two cases, the MXA stain was strikingly positive, the surrogate type I interferon marker that is typically upregulated in biopsies of LE and DM. There are eight prior reported cases describing SPTCL with concomitant cutaneous changes of LE. In six cases there was an established history of LE, including LP responding initially to Plaquenil, similar to one of our cases. In the context of SPTCL or panniculitic PGD-TCL, panniculitic T-cell lymphomas can be associated with concomitant clinical and histologic features of LE or DM, including an upregulated type I interferon signature. Identifying histologic features associated with either of these prototypic autoimmune conditions should not be considered exclusionary to diagnosing any panniculitic T-cell lymphoma. A clinical, histomorphologic, and pathophysiologic continuum exists with LP, SPTCL and panniculitic PGD-TCL.

Insights into COVID-19: Perspectives on Drug Remedies and Host Cell Responses

In light of the COVID-19 global pandemic caused by SARS-CoV-2, ongoing research has centered on minimizing viral spread either by stopping viral entry or inhibiting viral replication. Repurposing antiviral drugs, typically nucleoside analogs, has proven successful at inhibiting virus replication. This review summarizes current information regarding coronavirus classification and characterization and presents the broad clinical consequences of SARS-CoV-2 activation of the angiotensin-converting enzyme 2 (ACE2) receptor expressed in different human cell types. It provides publicly available knowledge on the chemical nature of proposed therapeutics and their target biomolecules to assist in the identification of potentially new drugs for the treatment of SARS-CoV-2 infection.

Patients with Systemic Juvenile Idiopathic Arthritis (SJIA) Show Differences in Autoantibody Signatures Based on Disease Activity

Systemic juvenile idiopathic arthritis (SJIA) is a severe rheumatic disease in children. It is a subgroup of juvenile idiopathic arthritis (JIA; MIM #604302), which is the most common rheumatic disease in children. The diagnosis of SJIA often comes with a significant delay, and the classification between autoinflammatory and autoimmune disease is still discussed. In this study, we analyzed the immunological responses of patients with SJIA, using human proteome arrays presenting immobilized recombinantly expressed human proteins, to analyze the involvement of autoantibodies in SJIA. Results from group comparisons show several differentially reactive antigens involved in inflammatory processes. Intriguingly, many of the identified antigens had a high reactivity against proteins involved in the NF-κB pathway, and it is also notable that many of the detected DIRAGs are described as dysregulated in rheumatoid arthritis. Our data highlight novel proteins and pathways potentially dysregulated in SJIA and offer a unique approach to unraveling the underlying disease pathogenesis in this chronic arthropathy.

Immunobiology of pregnancy: from basic science to translational medicine

Embryo implantation failure and spontaneous abortions represent the main causes of infertility in developed countries. Unfortunately, incomplete knowledge of the multiple factors involved in implantation and fetal development keeps the success rate of medically assisted procreation techniques relatively low. According to recent literature, cellular and molecular mechanisms of 'immunogenic tolerance' towards the embryo are crucial to establish an 'anti-inflammatory' state permissive of a healthy pregnancy. In this review we dissect the role played by the immune system in the endometrial-embryo crosstalk, with a particular emphasis towards the fork-head-box-p3 (Foxp3+) CD4+CD25+ regulatory T (Treg) cells and discuss the most recent therapeutic advances in the context of early immune-mediated pregnancy loss.

Severe Bone Marrow Aplasia Following Macrophage Activation Syndrome in Systemic Lupus Erythematosus

Macrophage activation syndrome (MAS) is a potentially fatal complication of rheumatic diseases, characterized by activated macrophages with hemophagocytosis and multiple organ damage. We report a case of MAS associated with systemic lupus erythematosus that initially presented with severe liver dysfunction. Although it was improved with steroids and plasmapheresis, severe pancytopenia was subsequently experienced, and the bone marrow showed severe aplasia similar to aplastic anemia. Nevertheless, the administration of immunosuppressants resulted in the recovery of blood counts within two weeks. When severe MAS results in cytokine overproduction, bone marrow aplasia may occur, for which immunosuppressive therapy may be highly effective.

Epigallocatechin gallate (EGCG) inhibits lipopolysaccharide-induced inflammation in RAW 264.7 macrophage cells via modulating nuclear factor kappa-light-chain enhancer of activated B cells (NF-κB) signaling pathway

Epigallocatechin-3-gallate (EGCG) is a major bioactive compound in tea polyphenol extract. After ingestion, EGCG reaches the intestine and may commence anti-inflammation in the intestinal organ. Thus, in this paper, the anti-inflammatory effect of EGCG was studied using lipopolysaccharide (LPS)-induced inflammation in RAW 264.7 cells. LPS induction instigated morphological deformation extensively which was normalized by EGCG. In LPS-induced macrophage cells, EGCG was found to lower cellular nitric oxide (32% of LPS group) and intercellular ROS level (45.4% of LPS group). It also suppressed the expression of IL-1β (LPS 132.6 ± 14.6, EGCG 10.67 ± 3.65), IL-6 (LPS 2994.44 ± 178.5, EGCG 408.33 ± 52.34), TNF-α (LPS 27.11 ± 2.84, EGCG 1.22 ± 0.03), and iNOS (LPS 40.45 ± 11.17, EGCG 10.24 ± 0.89). The GO function analysis identified that these differential genes involved 24 biological processes, 18 molecular functions, and 19 cellular component-related processes. KEGG pathway enrichment analysis revealed that LPS significantly affects NF-κB, TNF, and TLR signaling pathways. Western blotting revealed that EGCG diminished P-IκB/IκB ratio by 75% and p-p65/p65 by 50% compared to the LPS group. Finally, Arg-1 and CD-206 mRNA expression were determined by RT-PCR, which was consistent with the RNA-Seq result. These findings indicate that EGCG exerts an anti-inflammatory effect by reducing NO and ROS production, suppressing TLR4 protein expression, and inhibiting IκB and p65 phosphorylation.

Severe and life-threatening onset of systemic lupus erythematosus

Macrophage activation syndrome (MAS) is a potentially life-threatening complication of rheumatic diseases. We report a unique case of a previously healthy 20-year-old female presenting with MAS as first presentation of systemic lupus erythematosus. Remission was achieved with hydroxychloroquine, intravenous methylprednisolone pulse followed by oral prednisolone and cyclosporine. However, the management of MAS is still challenging, and the mortality rate remains high.

Cytokines, chemokines, and cells growth factors in patients with mild to moderate SARS-CoV-2 infection: A case-control study

Several biomarkers have been evaluated as predictors of severity or in directing the treatment of COVID-19, however there are no conclusive results. In this study, we evaluated serum levels of cytokines, chemokines, and cell growth factors in association with the pathobiology of mild to moderate SARS-CoV-2 infection. Serum levels of SARS-CoV-2 infected patients (n = 113) and flu symptoms individuals negative for SARS-CoV-2 (n = 58), tested by the RT-qPCR test-nasal swab were compared to healthy controls (n = 53). Results showed that the proinflammatory cytokines IL-1β, MCP-3, TNF-α, and G-CSF were increased in symptomatic patients and the cytokines IL-6 and IL-10 were associated with patients positive for SARS-CoV-2 when compared to healthy controls. Symptoms associated with COVID-19 were fever, anosmia, ageusia, and myalgia. For patients without SARS-CoV-2 infection, their major symptom was sore throat. The pathobiology of mild to moderate SARS-CoV-2 infection was associated with increasing proinflammatory cytokines and a pleiotropic IL-6 and anti-inflammatory IL-10 cytokines compared to healthy controls. Thus, knowledge about the pathophysiology and the involvement of biomarkers in the mild to moderate profile of the disease should be evaluated. Monitoring these biomarkers in patients with mild to moderate disease can help establish adequate treatment and prevention strategies for long-term COVID-19.

IL-18 in Autoinflammatory Diseases: Focus on Adult Onset Still Disease and Macrophages Activation Syndrome

Interleukin-18 (IL-18) is a potent pro-inflammatory cytokine that is involved in various innate and adaptive immune processes related to infection, inflammation, and autoimmunity. Therefore, it is described as a key mediator of autoinflammatory diseases associated with the development of macrophage activation syndrome (MAS), including systemic juvenile idiopathic arthritis and adult-onset Still's disease. This review focuses on the role of IL-18 in inflammatory responses, placing emphasis on autoinflammatory diseases associated with chronic excess of serum IL-18, which correlate with clinical and biological signs of the disease. Therefore, it is useful for the diagnosis and monitoring of disease activity. Researchers are currently investigating IL-18's role as a therapeutic target for the treatment of inflammatory diseases. The inhibition of IL-18 signaling through recombinant human IL-18BP (IL-18 binding protein) seems to be an effective therapeutic strategy, though further studies are necessary to clarify its importance as a therapeutic target.

Clinical value of soluble fms-like tyrosine kinase 1 (sFlt-1) in adult secondary hemophagocytic lymphohistiocytosis

BACKGROUND

Secondary hemophagocytic lymphohistiocytosis (sHLH) is a syndrome characterized by an excessive systemic inflammatory response, manifested by multiple organ dysfunction, lacking reliable immune biomarkers for predicting their inflammatory status and prognosis. Soluble fms-like tyrosine kinase 1 (sFlt-1) is associated with various inflammation-related diseases, including sepsis and severe organ failure.

METHODS

This study retrospectively included 32 adult sHLH patients diagnosed from January 2020 to December 2021. The expression of Flt-1 in peripheral blood CD14 + monocytes was detected by flow cytometry, and the level of plasma sFlt-1 was detected by ELISA.

RESULTS

In our study, the results of flow cytometry reveal that the Flt-1 expression on CD14 + monocytes of peripheral blood from sHLH patients was higher than that in normal control. In plasma samples of sHLH patients, sFlt-1 levels were 677.8 (463.2-929.7) pg/mL, significantly higher than in normal controls 377.18 (350.4-424.6) pg/mL and sepsis group 378.3 (257.0-499.1) pg/mL. Besides, a positive correlation was found between sFlt-1 and IL-6 in sHLH patients. The analysis of univariate Cox regression indicated that sFlt-1 >681.5 pg/mL demonstrated unfavorable overall survival ( p = 0.022). Multivariate analysis demonstrated that sFlt-1 >681.5 pg/mL was an independent factor associated with OS ( p = 0.041) after adjustment for confounders. Restricted cubic spline confirmed a linear and positive association between sFlt-1 and mortality risk.

CONCLUSION

Retrospective analysis showed that sFlt-1 was a promising prognostic factor.

Impacts of SARS-CoV-2 on diabetes mellitus: A pre and post pandemic evaluation

The coronavirus disease 2019 (COVID-19) pandemic caused by the novel beta coronavirus severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) crippled the whole world and has resulted in large number of morbidity and mortality. The origin of the SARS-CoV-2 is still disputed. The risk of infection with SARS-CoV-2 is dependent on several risk factors as observed in many studies. The severity of the disease depends on many factors including the viral strain, host immunogenetics, environmental factors, host genetics, host nutritional status and presence of comorbidities like hypertension, diabetes, Chronic Obstructive Pulmonary Disease, cardiovascular disease, renal impairment. Diabetes is a metabolic disorder mainly characterized by hyperglycemia. Diabetic individuals are intrinsically prone to infections. SARS-CoV-2 infection in patients with diabetes result in β-cell damage and cytokine storm. Damage to the cells impairs the equilibrium of glucose, leading to hyperglycemia. The ensuing cytokine storm causes insulin resistance, especially in the muscles and liver, which also causes a hyperglycemic state. All of these increase the severity of COVID-19. Genetics also play pivotal role in disease pathogenesis. This review article focuses from the probable sources of coronaviruses and SARS-CoV-2 to its impacts on individuals with diabetes and host genetics in pre- and post-pandemic era.

Immune mechanisms underlying COVID-19 pathology and post-acute sequelae of SARS-CoV-2 infection (PASC)

With a global tally of more than 500 million cases of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections to date, there are growing concerns about the post-acute sequelae of SARS-CoV-2 infection (PASC), also known as long COVID. Recent studies suggest that exaggerated immune responses are key determinants of the severity and outcomes of the initial SARS-CoV-2 infection as well as subsequent PASC. The complexity of the innate and adaptive immune responses in the acute and post-acute period requires in-depth mechanistic analyses to identify specific molecular signals as well as specific immune cell populations which promote PASC pathogenesis. In this review, we examine the current literature on mechanisms of immune dysregulation in severe COVID-19 and the limited emerging data on the immunopathology of PASC. While the acute and post-acute phases may share some parallel mechanisms of immunopathology, it is likely that PASC immunopathology is quite distinct and heterogeneous, thus requiring large-scale longitudinal analyses in patients with and without PASC after an acute SARS-CoV-2 infection. By outlining the knowledge gaps in the immunopathology of PASC, we hope to provide avenues for novel research directions that will ultimately lead to precision therapies which restore healthy immune function in PASC patients.

Pathogenic Gene Spectrum and Clinical Implication in Chinese Patients with Lupus Nephritis

BACKGROUND

Lupus nephritis is a rare immunological disorder. Genetic factors are considered important in its causation. We aim to systematically investigate the rare pathogenic gene variants in patients with lupus nephritis.

METHODS

Whole-exome sequencing was used to screen pathogenic gene variants in 1886 probands with lupus nephritis. Variants were interpreted on the basis of known pathogenic variants or the American College of Medical Genetics and Genomics guidelines and studied by functional analysis, including RNA sequencing, quantitative PCR, cytometric bead array, and Western blotting.

RESULTS

Mendelian form of lupus nephritis was confirmed in 71 probands, involving 63 variants in 39 pathogenic genes. The detection yield was 4%. The pathogenic genes enriched in nuclear factor kappa-B (NF-κB), type I interferon, phosphatidylinositol-3-kinase/serine/threonine kinase Akt (PI3K/AKT), Ras GTPase/mitogen-activated protein kinase (RAS/MAPK), and Janus kinase/signal transducer and activator of transcription (JAK/STAT) pathways. Clinical manifestation patterns were diverse among different signaling pathways. More than 50% of the pathogenic gene variants were reported to be associated with lupus or lupus nephritis for the first time. The identified pathogenic gene variants of lupus nephritis overlapped with those of autoinflammatory and immunodeficiency diseases. Inflammatory signatures, such as cytokine levels of IL-6, IL-8, IL-1 β , IFN α , IFN γ , and IP10 in serum and transcriptional levels of interferon-stimulated genes in blood, were significantly higher in patients with pathogenic gene variants compared with controls. The overall survival rate of patients with pathogenic gene variants was lower than those without pathogenic gene variants.

CONCLUSIONS

A small fraction of patients with lupus nephritis had identifiable pathogenic gene variants, primarily in NF-κB, type I interferon, PI3K/AKT, JAK/STAT, RAS/MAPK, and complement pathways.

Mouse models of systemic juvenile idiopathic arthritis and macrophage activation syndrome

Macrophage activation syndrome (MAS) is a life-threatening complication of pediatric rheumatic diseases, occurring most commonly in children with systemic juvenile idiopathic arthritis (SJIA). Despite several classes of currently available treatment options for SJIA, including biologic agents targeting IL-1 or IL-6, there remain severe cases suffering from refractory disease and recurrent MAS. The phenotype of MAS is similar to hemophagocytic lymphohistiocytosis (HLH), but the underlying pathophysiology of MAS complicating SJIA or other disorders has not been fully clarified. These facts make it challenging to develop and utilize animal models to study MAS. To date, there is no "perfect" model replicating MAS, but several models do demonstrate aspects of SJIA and/or MAS. In this review, we examine the proposed animal models of SJIA and MAS, focusing on how they reflect these disorders, what we have learned from the models, and potential future research questions. As we better understand the key features of each, animal models can be powerful tools to further define the pathophysiology of SJIA and MAS, and develop new treatment targets and strategies.

The biology of VSIG4: Implications for the treatment of immune-mediated inflammatory diseases and cancer

V-set and immunoglobulin domain containing 4 (VSIG4), a type I transmembrane receptor exclusively expressed in a subset of tissue-resident macrophages, plays a pivotal role in clearing C3-opsonized pathogens and their byproducts from the circulation. VSIG4 maintains immune homeostasis by suppressing the activation of complement pathways or T cells and inducing regulatory T-cell differentiation, thereby inhibiting the development of immune-mediated inflammatory diseases but enhancing cancer progression. Consequently, VSIG4 exhibits a potential therapeutic effect for immune-mediated inflammatory diseases, but also is regarded as a novel target of immune checkpoint inhibition in cancer therapy. Recently, soluble VSIG4, the extracellular domain of VSIG4, shed from the surface of macrophages, has been found to be a biomarker to define macrophage activation-related diseases. This review mainly summarizes recent new findings of VSIG4 in macrophage phagocytosis and immune homeostasis, and discusses its potential diagnostic and therapeutic usage in infection, inflammation, and cancer.

Complications of complications: diagnosis and treatment of recurrent macrophage activation syndrome in a patient with well-controlled systemic juvenile idiopathic arthritis

Macrophage activation syndrome (MAS) is a subtype of haemophagocytic lymphohistiocytosis (HLH), and a well-described complication of systemic juvenile idiopathic arthritis (SJIA), triggered by disease onset or flare, infection, or some medications. Here, we report a 20-year-old man with previously well-controlled SJIA, who developed first time MAS after acute Epstein-Barr virus (EBV) infection, with MAS recurrence due to a drug reaction, '3-week sulfasalazine syndrome', secondary to prophylactic trimethoprim/sulfamethoxazole. Both episodes of MAS were minimally responsive to pulse corticosteroids. Initial EBV-driven MAS was treated with multiple doses of emapalumab prior to resolution, while MAS secondary to sulfasalazine-induced 3-week syndrome required the initiation of ruxolitinib. This case exhibits two rare but life-threatening causes of MAS/secondary HLH in a single patient and the difficulties in their diagnosis and management.

Hemophagocytic Lymphohistiocytosis Associated With Cytomegalovirus Infection: 5 Cases and a Systematic Review of the Literature

Hemophagocytic lymphohistiocytosis (HLH) is a rare, life-threatening disorder characterized by an uncontrolled, persistent, hyperimmune response. It can be triggered by an infectious, neoplastic, or autoimmune event. The involvement of cytomegalovirus (CMV) in the onset of HLH is subject to debate, and the epidemiology of CMV-associated HLH (HLH-CMV) remains poorly characterized. We identified 5 cases of HLH-CMV in our hospital, systematically searched the PubMed database for publications on HLH-CMV, and reviewed 57 publications with a total of 67 cases of HLH-CMV. Only 48 patients (71.6%) were immunodeficient, suggesting that HLH-CMV can occur in immunocompetent patients. The major cause of underlying immunodepression (51%) was inflammatory bowel disease (mainly treated with azathioprine). CMV infection was nearly always symptomatic, and lung involvement was frequent (31 cases). Fifty-five patients recovered. Nineteen patients were treated for CMV infection only and had a good outcome, suggesting that antiviral drugs might be the cornerstone of HLH-CMV treatment.

BPOZ-2 is a negative regulator of the NLPR3 inflammasome contributing to SARS-CoV-2-induced hyperinflammation

Introduction

Inflammation play important roles in the initiation and progression of acute lung injury (ALI), acute respiratory distress syndrome (ARDS), septic shock, clotting dysfunction, or even death associated with SARS-CoV-2 infection. However, the pathogenic mechanisms underlying SARS-CoV-2-induced hyperinflammation are still largely unknown.

Methods

The animal model of septic shock and ALI was established after LPS intraperitoneal injection or intratracheal instillation. Bone marrow-derived macrophages (BMDMs) from WT and BPOZ-2 KO mouse strains were harvested from the femurs and tibias of mice. Immunohistology staining, ELISA assay, coimmunoprecipitation, and immunoblot analysis were used to detect the histopathological changes of lung tissues and the expression of inflammatory factors and protein interaction.

Results and conclusions

We show a distinct mechanism by which the SARS-CoV-2 N (SARS-2-N) protein targets Bood POZ-containing gene type 2 (BPOZ-2), a scaffold protein for the E3 ubiquitin ligase Cullin 3 that we identified as a negative regulator of inflammatory responses, to promote NLRP3 inflammasome activation. We first demonstrated that BPOZ-2 knockout (BPOZ-2 KO) mice were more susceptible to lipopolysaccharide (LPS)-induced septic shock and ALI and showed increased serum IL-1β levels. In addition, BMDMs isolated from BPOZ-2 KO mice showed increased IL-1β production in response to NLRP3 stimuli. Mechanistically, BPOZ-2 interacted with NLRP3 and mediated its degradation by recruiting Cullin 3. In particular, the expression of BPOZ-2 was significantly reduced in lung tissues from mice infected with SARS-CoV-2 and in cells overexpressing SARS-2-N. Importantly, proinflammatory responses triggered by the SARS-2-N were significantly blocked by BPOZ-2 reintroduction. Thus, we concluded that BPOZ-2 is a negative regulator of the NLPR3 inflammasome that likely contributes to SARS-CoV-2-induced hyperinflammation.

Prognostic value of lipid profile in adult hemophagocytic lymphohistiocytosis

Background

Adult secondary hemophagocytic lymphohistiocytosis (sHLH) is a rare clinical syndrome with a high mortality rate. Currently, there are no feasible prognostic factors to clinically predict untreated sHLH patients' prognosis. Our objective was to characterize the lipid profile of adult sHLH patients and to determine the relationship with overall survival.

Methods

We retrospectively analyzed 247 patients with newly diagnosed sHLH from January 2017 to January 2022 according to the HLH-2004 criteria. Multivariate Cox regression analyses and restricted cubic splines were conducted to evaluate the prognostic value of the lipid profile.

Results

The median age of all patients was 52 years, and the commonest cause of sHLH in our cohort was malignancy. During a median follow-up of 88 (interquartile ranges, 22-490) days, 154 deaths occurred. The univariate analysis confirmed total cholesterol (TC) ≤ 3 mmol/L, triglycerides (TG) > 3.08 mmol/L, high-density lipoprotein cholesterol (HDL-c) ≤ 0.52 mmol/L, and low-density lipoprotein cholesterol (LDL-c) ≤ 2.17 mmol/L were associated with an inferior survival. In a multivariate model, HDL-c, hemoglobin, platelet, fibrinogen, and soluble interleukin-2 receptor were considered as independent factors. Additionally, the restricted cubic spline analyses indicated an inverse linear association between HDL-c and the risk of mortality in sHLH.

Conclusion

Lipid profiles, which were low-cost and readily available promising biomarkers, were strongly associated with the overall survival in adult sHLH patients.

Evaluation and validation of the prognostic value of anti-MDA5 IgG subclasses in dermatomyositis-associated interstitial lung disease

OBJECTIVE

To investigate the association between the anti-melanoma differentiation associated gene 5 (MDA5) IgG subclasses and prognosis of patients with dermatomyositis (DM)-associated interstitial lung disease (ILD).

METHODS

This retrospective study included 122 anti-MDA5 positive DM-ILD patients admitted from October 2017 to October 2020 as training cohort, and additional 68 patients from August 2014 to September 2017 as validation cohort. The levels of anti-MDA5 total IgG and IgG subclasses were measured using in-house enzyme-linked immunosorbent assays, and analysed in association with the patient prognosis.

RESULTS

In the training cohort, the concentrations of anti-MDA5 IgG1 and IgG3 in non-survivors were significantly higher than in survivors (P < 0.05), whereas there were no significant differences in the IgG2 and IgG4 levels. Kaplan-Meier survival analysis revealed that the levels of anti-MDA5 total IgG, IgG1 and IgG3 were associated with mortality (P < 0.05). Multivariate analysis revealed anti-MDA5 IgG1 >13 U/ml and anti-MDA5 IgG3 >11 U/ml were independent risk factors for death of DM-ILD patients (P < 0.05). Anti-MDA5 IgG1 was confirmed as an independent risk factor in the validation cohort, while anti-MDA5 IgG3 was not. Anti-MDA5 IgG1 showed greater discriminable power for patient prognosis (Youden index 0.494) than anti-MDA5 total IgG, IgG3, or the combination of IgG1 and IgG3 (Youden index 0.356, 0.32 and 0.447, respectively).

CONCLUSION

Anti-MDA5 IgG1 and IgG3 are significantly associated with poor prognosis in DM-ILD patients, and anti-MDA5 IgG1 is more efficient as a prognostic biomarker in DM-ILD patients.

Refractory adult-onset Still's disease complicated with monoclonal gammopathy of undetermined significance: A case report

RATIONALE

Adult-onset Still's disease (AOSD) is a rare inflammatory disease characterized by a classic triad of daily spike fever, arthritis, and a typical salmon-pink rash. The involvement of inflammatory cytokines by various factors such as infection, drug, or neoplasm causes refractory AOSD.

PATIENT CONCERNS

We report a 63-year-old man with a high fever, rash, hyperferritinemia, and M proteinemia. His serum levels of interleukin-6 and interleukin-18 were remarkably high at 192 and 114,250 pg/mL, respectively.

DIAGNOSIS

AOSD complicated with monoclonal gammopathy of undetermined significance was diagnosed.

INTERVENTIONS

After steroid pulse therapy followed by oral prednisolone, cyclosporin, methotrexate, and colchicine, serum ferritin levels temporarily declined, but secondary cytomegalovirus infections exacerbated AOSD's activity.

OUTCOMES

Finally, after tocilizumab induction, AOSD activity was gradually suppressed over a long period.

LESSONS

The disease activity of AOSD is exacerbated by multiple factors, including comorbidities or infections. Clinicians need to consider that monoclonal gammopathy of undetermined significance complications might become AOSD refractory by an elevation of the inflammatory cytokines. Moreover, further prospective studies are required to confirm this result.

Lung Involvement in Systemic Juvenile Idiopathic Arthritis: A Narrative Review

Systemic juvenile idiopathic arthritis associated with lung disorders (sJIA-LD) is a subtype of sJIA characterized by the presence of chronic life-threatening pulmonary disorders, such as pulmonary hypertension, interstitial lung disease, pulmonary alveolar proteinosis and/or endogenous lipoid pneumonia, which were exceptionally rare before 2013. Clinically, these children show a striking dissociation between the relatively mild clinical manifestations (tachypnoea, clubbing and chronic cough) and the severity of the pulmonary inflammatory process. Our review describes sJIA-LD as having a reported prevalence of approximately 6.8%, with a mortality rate of between 37% and 68%. It is often associated with an early onset (<2 years of age), macrophage activation syndrome and high interleukin (IL)-18 circulating levels. Other risk factors may be trisomy 21 and a predisposition to adverse reactions to biological drugs. The most popular hypothesis is that the increase in the number of sJIA-LD cases can be attributed to the increased use of IL-1 and IL-6 blockers. Two possible explanations have been proposed, named the “DRESS hypothesis” and the “cytokine plasticity hypothesis”. Lung ultrasounds and the intercellular-adhesion-molecule-5 assay seem to be promising tools for the early diagnosis of sJIA-LD, although high resolution computed tomography remains the gold standard. In this review, we also summarize the treatment options for sJIA-LD, focusing on JAK inhibitors.

The Role of Immune Mechanisms, Inflammatory Pathways, and Macrophage Activation Syndrome in the Pathogenesis of Hemophagocytic Lymphohistiocytosis

This review article describes the pathophysiology of hemophagocytic lymphohistiocytosis (HLH). The condition is characterized by excessive stimulation of inflammatory cytokines, lymphocytes, and macrophages, leading to hyperinflammatory disorder with immune dysfunction. The main clinical and diagnostic features include fever ≥38.5°C, splenomegaly, hyperferritinemia, cytopenia, hypofibrinogenemia, hemophagocytosis on the bone marrow, low or absent of natural killer (NK) cell activity, and elevated soluble CD25. Various immunological and inflammatory mechanisms are involved in the pathogenesis of HLH. Moreover, the condition can result in multisystem organ failure, contributing to the high mortality rate in hospital settings. A thorough literature search was conducted by collecting data from multiple articles published on PubMed, Medline, and Google Scholar. The article discusses the cellular and molecular pathways that lead to HLH. Due to the high rate of morbidity and mortality, early diagnosis needs to be established. More research pertaining to molecular biology, immunology, and the genetics of HLH is needed to explore the effective management and treatment of this rare disorder.

Refractory systemic onset juvenile idiopathic arthritis: current challenges and future perspectives

Systemic juvenile idiopathic arthritis (SJIA) is a rare disease with distinct features not seen in other categories of juvenile idiopathic arthritis. In recent years, advances in the understanding of disease immunopathogenesis have led to improved targeted therapies with significant improvement in patient outcomes. Despite these advances, there remain subsets of SJIA with refractory disease and severe disease-associated complications. This review highlights existing options for treatment of refractory SJIA and explores potential future therapeutics for refractory disease.Key Points:Despite targeted Interleukin IL-1 and IL-6 inhibitors a subset of SJIA remains refractory to therapy. About 1 in 7 SJIA patients will be refractory to targeted IL-1 or IL-6 therapy.There is no current agreed upon definition for refractory SJIA and we propose in this review that refractory SJIA is presence of active systemic or arthritic features despite treatment with anti-IL-1 or anti-IL-6 therapy or disease requiring glucocorticoids for control beyond 6 months.SJIA disease associated complications include presence of associated macrophage activation syndrome (MAS), interstitial lung disease (ILD) or amyloidosis and management of each differs.Refractory SJIA treatment options currently include additional conventional synthetic disease modifying anti-rheumatic drugs (csDMARDS), biologic (bDMARDS), combination biologic therapy, targeted synthetic (tsDMARDS) or other immunomodulatory therapies.

Genetic and pharmacological targeting of GSDMD ameliorates systemic inflammation in macrophage activation syndrome

Macrophage activation syndrome (MAS), a potentially life-threatening complication of autoimmune/autoinflammatory diseases, is characterized by the excessive expansion and activation of macrophages and cytotoxic T lymphocytes in multiple organs. Most commonly, MAS occurs in patients with systemic juvenile idiopathic arthritis and in its adult equivalent, adult-onset Still's disease (AOSD). Gasdermin D (GSDMD) is a critical pore-forming effector protein that mediates pro-inflammatory cytokine secretion via releasing its N terminal fragments to form transmembrane pores. GSDMD has been implicated in various inflammatory diseases, however, its role in MAS remains elusive. Here, we unveiled that the serum levels of GSDMD-N were elevated in patients with AOSD compared to heathy controls. In addition, the emergence of MAS features in AOSD patients resulted in further elevation. The serum levels of GSDMD were positively correlated with ferritin and interleukin-18 (IL-18). Repeated toll-like receptor 9 stimulation with unmethylated cytosine-phosphate-guanine (CpG) induced MAS symptoms in wild-type mice, including body weight loss, pancytopenia and hepatosplenomegaly. Genetic deletion and pharmacological inhibition of GSDMD ameliorated MAS symptoms in mice with the concomitant reduction of splenic and hepatic macrophage infiltration and IL-18 production. Consistent with these in vivo results, bone marrow-derived macrophages obtained from GSDMD^-/- mice or treated with GSDMD inhibitor disulfiram exhibited attenuated IL-18 expression after CpG stimulation. Collectively, our findings identified GSDMD as a novel marker for MAS complication and a promising target for MAS treatment.

Biomarkers in Systemic Juvenile Idiopathic Arthritis, Macrophage Activation Syndrome and Their Importance in COVID Era

Systemic juvenile idiopathic arthritis (sJIA) and its complication, macrophage activation syndrome (sJIA-MAS), are rare but sometimes very serious or even critical diseases of childhood that can occasionally be characterized by nonspecific clinical signs and symptoms at onset-such as non-remitting high fever, headache, rash, or arthralgia-and are biologically accompanied by an increase in acute-phase reactants. For a correct positive diagnosis, it is necessary to rule out bacterial or viral infections, neoplasia, and other immune-mediated inflammatory diseases. Delays in diagnosis will result in late initiation of targeted therapy. A set of biomarkers is useful to distinguish sJIA or sJIA-MAS from similar clinical entities, especially when arthritis is absent. Biomarkers should be accessible to many patients, with convenient production and acquisition prices for pediatric medical laboratories, as well as being easy to determine, having high sensitivity and specificity, and correlating with pathophysiological disease pathways. The aim of this review was to identify the newest and most powerful biomarkers and their synergistic interaction for easy and accurate recognition of sJIA and sJIA-MAS, so as to immediately guide clinicians in correct diagnosis and in predicting disease outcomes, the response to treatment, and the risk of relapses. Biomarkers constitute an exciting field of research, especially due to the heterogeneous nature of cytokine storm syndromes (CSSs) in the COVID era. They must be selected with utmost care-a fact supported by the increasingly improved genetic and pathophysiological comprehension of sJIA, but also of CSS-so that new classification systems may soon be developed to define homogeneous groups of patients, although each with a distinct disease.

Neuropilin-1 in the pathogenesis of preeclampsia, HIV-1, and SARS-CoV-2 infection: A review

This review explores the role of transmembrane neuropilin-1 (NRP-1) in pregnancy, preeclampsia (PE), human immunodeficiency virus type 1 (HIV-1) and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections. Since these conditions are assessed independently, this review attempts to predict their comorbid clinical manifestations. Dysregulation of NRP-1 contributes to the pathogenesis of PE by (a) impairing vascular endothelial growth factor (VEGF) signaling for adequate spiral artery remodeling and placentation, (b) inducing syncytiotrophoblast (ST) cell apoptosis and increasing ST-derived microparticle circulation and (c) by decreasing regulatory T cell activity predisposing maternal immune intolerance. Although NRP-1 is upregulated in SARS-CoV-2 placentae, its exploitation for SARS-CoV-2 internalization and increased infectivity may alter angiogenesis through the competitive inhibition of VEGF. The anti-inflammatory nature of NRP-1 may aid its upregulation in HIV-1 infection; however, the HIV-accessory protein, tat, reduces NRP-1 expression. Upregulated NRP-1 in macrophages and dendritic cells also demonstrated HIV-1 resistance/reduced infectivity. Notably, HIV-1-infected pregnant women receiving antiretroviral therapy (ART) to prevent vertical transmission may experience immune reconstitution, impaired decidualization, and elevated markers of endothelial injury. Since endothelial dysfunction and altered immune responses are central to PE, HIV-1 infection, ART usage and SARS-CoV-2 infection, it is plausible that an exacerbation of both features may prevail in the synergy of these events. Additionally, this review identifies microRNAs (miRNAs) mediating NRP-1 expression. MiR-320 and miR-141 are overexpressed in PE, while miR-206 and miR-124-3p showed increased expression in PE and HIV-1 infection. Additionally, miR-214 is overexpressed in PE, HIV-1 and SARS-CoV-2 infection, implicating treatment strategies to reduce these miRNAs to upregulate and normalize NRP-1 expression. However, inconsistencies in the data of the role and regulation of miRNAs in PE, HIV-1 and SARS-CoV-2 infections require clarification. This review provides a platform for early diagnosis and potential therapeutic intervention of PE, HIV-1, and SARS-CoV-2 infections independently and as comorbidities.

Role of Innate and Adaptive Cytokines in the Survival of COVID-19 Patients

SARS-CoV-2 is a new coronavirus characterized by a high infection and transmission capacity. A significant number of patients develop inadequate immune responses that produce massive releases of cytokines that compromise their survival. Soluble factors are clinically and pathologically relevant in COVID-19 survival but remain only partially characterized. The objective of this work was to simultaneously study 62 circulating soluble factors, including innate and adaptive cytokines and their soluble receptors, chemokines and growth and wound-healing/repair factors, in severe COVID-19 patients who survived compared to those with fatal outcomes. Serum samples were obtained from 286 COVID-19 patients and 40 healthy controls. The 62 circulating soluble factors were quantified using a Luminex Milliplex assay. Results. The patients who survived had decreased levels of the following 30 soluble factors of the 62 studied compared to those with fatal outcomes, therefore, these decreases were observed for cytokines and receptors predominantly produced by the innate immune system—IL-1α, IL-1α, IL-18, IL-15, IL-12p40, IL-6, IL-27, IL-1Ra, IL-1RI, IL-1RII, TNFα, TGFα, IL-10, sRAGE, sTNF-RI and sTNF-RII—for the chemokines IL-8, IP-10, MCP-1, MCP-3, MIG and fractalkine; for the growth factors M-CSF and the soluble receptor sIL2Ra; for the cytokines involved in the adaptive immune system IFNγ, IL-17 and sIL-4R; and for the wound-repair factor FGF2. On the other hand, the patients who survived had elevated levels of the soluble factors TNFβ, sCD40L, MDC, RANTES, G-CSF, GM-CSF, EGF, PDGFAA and PDGFABBB compared to those who died. Conclusions. Increases in the circulating levels of the sCD40L cytokine; MDC and RANTES chemokines; the G-CSF and GM-CSF growth factors, EGF, PDGFAA and PDGFABBB; and tissue-repair factors are strongly associated with survival. By contrast, large increases in IL-15, IL-6, IL-18, IL-27 and IL-10; the sIL-1RI, sIL1RII and sTNF-RII receptors; the MCP3, IL-8, MIG and IP-10 chemokines; the M-CSF and sIL-2Ra growth factors; and the wound-healing factor FGF2 favor fatal outcomes of the disease.

Human pluripotent stem cell-derived macrophages and macrophage-derived exosomes: therapeutic potential in pulmonary fibrosis

Pulmonary fibrosis (PF) is a fatal chronic disease characterized by accumulation of extracellular matrix and thickening of the alveolar wall, ultimately leading to respiratory failure. PF is thought to be initiated by the dysfunction and aberrant activation of a variety of cell types in the lung. In particular, several studies have demonstrated that macrophages play a pivotal role in the development and progression of PF through secretion of inflammatory cytokines, growth factors, and chemokines, suggesting that they could be an alternative therapeutic source as well as therapeutic target for PF. In this review, we describe the characteristics, functions, and origins of subsets of macrophages involved in PF and summarize current data on the generation and therapeutic application of macrophages derived from pluripotent stem cells for the treatment of fibrotic diseases. Additionally, we discuss the use of macrophage-derived exosomes to repair fibrotic lung tissue.

Anti-inflammatory and Immunostimulant Therapy with Lactobacillus fermentum and Lactobacillus plantarum in COVID-19: A Literature Review

Inflammatory diseases are diseases characterized by inflammatory symptoms. Acute inflammatory disease can cause dysregulation of the inflammatory immune response, thereby inhibiting the development of protective immunity against infection. Among the acute inflammatory disease is COVID-19. The initial viral infection causes the antigen-presenting cells to detect the virus through a phagocytosis mechanism in the form of macrophage and dendritic cells. Lactobacillus fermentum and L. plantarum are gram-positive bacteria potentially serving as immunomodulators caused by inflammation and immune system response. Short-chain fatty acids (SCFA) produced by Lactobacillus can induce immune response through tolerogenic dendritic cells. This probiotic bacterium can induce the production of different cytokines or chemokines. Following the results of in vitro and in vivo tests, L. fermentum and L. plantarum can induce IL-10 release to activate regulatory T-cell and inhibit tumor necrosis factor-α (TNF-α) binding activity of nuclear factor kappa B (NF-κB). Literature review showed that dysregulation of inflammatory immune response disorders due to inflammatory disease could be treated using probiotic bacteria L. fermentum and L. plantarum. Therefore, it is necessary to conduct further studies on the potential of indigenous Indonesian strains of these two bacteria as anti-inflammatory and immunostimulants.

Evaluation of Macrophage Activation Syndrome in Patients with Systemic Juvenile Idiopathic Arthritis: A Single Center Experience

Objectives. Macrophage activation syndrome (MAS) is a severe complication of systemic juvenile arthritis (sJIA), and early diagnosis is critical for survival. The objective of this study was to evaluate the 2016 MAS classification criteria in a Danish sJIA cohort and to compare different sets of criteria for the early identification of MAS including the HLH-2004 diagnostic guidelines, MS score, and the ferritin/ESR ratio. Methods. Data was extracted from medical charts of 32 patients with sJIA from a single Danish paediatric rheumatology center diagnosed between January 2014 and June 2021. Patients who met the 2016 MAS classification criteria were classified as having MAS. From a receiver operating characteristic (ROC) plot, the area under the curve (AUC) was calculated for the prediction of patients with MAS according to the 2016 MAS classification criteria using either MS score or the ferritin/ESR ratio. Results. Of the cohort, eight (25%) patients were classified as having MAS according to the 2016 MAS classification criteria compared to only three (9.4%) patients fulfilling the HLH-2004 diagnostic guidelines, all of which had recurrent MAS. The ferritin/ESR ratio showed the highest sensitivity (100%) but the lowest specificity (72.2%). In comparison, the MS score had a higher specificity (90.9%) for the identification of MAS according to the 2016 classification criteria. In our cohort, the most optimal cut-off point for the ferritin/ESR ratio was ≥19.4 (sensitivity: 100%, specificity: 72.2%) and ≥ -1.5 for the MS score (sensitivity: 71.4%, specificity: 91.7%), respectively. Conclusion. The 2016 MAS classification criteria were a valuable tool in the discrimination of sJIA with and without MAS. The HLH-2004 diagnostic guidelines showed the lowest sensitivity, ferritin/ESR ratio, and the lowest specificity compared to the MS score where an acceptable high sensitivity and specificity was found.

Interleukin-18 Binding Protein in Immune Regulation and Autoimmune Diseases

Natural soluble antagonist and decoy receptor on the surface of the cell membrane are evolving as crucial immune system regulators as these molecules are capable of recognizing, binding, and neutralizing (so-called inhibitors) their targeted ligands. Eventually, these soluble antagonists and decoy receptors terminate signaling by prohibiting ligands from connecting to their receptors on the surface of cell membrane. Interleukin-18 binding protein (IL-18BP) participates in regulating both Th1 and Th2 cytokines. IL-18BP is a soluble neutralizing protein belonging to the immunoglobulin (Ig) superfamily as it harbors a single Ig domain. The Ig domain is essential for its binding to the IL-18 ligand and holds partial homology to the IL-1 receptor 2 (IL-1R2) known as a decoy receptor of IL-1α and IL-1β. IL-18BP was defined as a unique soluble IL-18BP that is distinct from IL-18Rα and IL-18Rβ chain. IL-18BP is encoded by a separated gene, contains 8 exons, and is located at chr.11 q13.4 within the human genome. In this review, we address the difference in the biological activity of IL-18BP isoforms, in the immunity balancing Th1 and Th2 immune response, its critical role in autoimmune diseases, as well as current clinical trials of recombinant IL-18BP (rIL-18BP) or equivalent.