Clinical characteristics and outcomes of COVID-19 in pediatric patients with rheumatic diseases.

BACKGROUND: This study investigates the clinical characteristics and outcomes of pediatric patients with rheumatic diseases infected with COVID-19 in China. METHODS: We conducted a retrospective analysis of pediatric patients with rheumatic diseases who contracted COVID-19. Data were collected via a comprehensive questionnaire with a 14-day follow-up. Multivariable logistic regression was used to assess severe outcomes, and network analyses evaluated symptom correlations. RESULTS: A total of 1070 cases were collected. Fever (88.05%) and cough (62.75%) were the most common symptoms. Cough, nasal congestion, and runny nose exhibited a stronger correlation with each other. A higher incidence of fever reduced the incidence of two single symptoms (nasal congestion [r = -0.833], runny nose [r = -0.762]). Vaccinated children showed a shorter time to negative COVID-19 conversion (7.21 days vs. 7.63 days, p < 0.05) and lower hospitalization rates (p = 0.025). Prolonged symptom duration was associated with older age (OR: 1.07 [1.04-1.11]; p < 0.001) and systemic lupus erythematosus (OR: 1.47 [1.01-2.12]; p = 0.046). CONCLUSIONS: Pediatric patients with rheumatic diseases exhibited a wide range of clinical symptoms after COVID-19 infection. The infection generally did not lead to severe outcomes in this study. COVID-19 vaccination was associated with reduced hospitalization risk and expediting the time to negativity for virus. IMPACTS: This manuscript demonstrates a comprehensive analysis of the clinical characteristics and outcomes of COVID-19 infection in pediatric patients with rheumatic diseases in China. It provides critical insights into the specific challenges faced by this vulnerable population and offers practical recommendations for improving patient management during periods of increased infectious risk.

Clinical prognostic impact of C-NLR in heart failure patients with different ejection fractions: a retrospective study.

OBJECTION: Inflammatory conditions and immune disorders may worsen the prognosis of chronic heart failure (CHF) patients. The aim of this study was to evaluate the prognostic value of a new indicator, C-NLR, composed of C-reactive protein (CRP) and neutrophil-to-lymphocyte ratio (NLR), for the risk of all-cause mortality in HF patients with different ejection fractions. METHODS: A total of 1221 CHF patients admitted to the First Affiliated Hospital of Kunming Medical University from January 2017 to October 2021 were enrolled in this study. All patients were divided into 2 groups according to the median C-NLR. Kaplan-Meier survival curves were used to compare the all-cause mortality among CHF patients with different ejection fractions. Cox proportional hazards analysis was used to evaluate the relationships between variables and mortality. The predictive value of the C-NLR was assessed by using receiver operating characteristic (ROC) analyses. RESULTS: We collected data from 1192 patients with CHF. Kaplan-Meier survival analysis revealed that patients with low LCR levels had better overall survival (OS). After multivariate adjustment Cox proportional hazards analysis, the level of C-NLR was still independently related to mortality. CONCLUSIONS: C-NLR was a competent independent predictor in HF with different ejection fractions, and routine measurement of C-NLR would help clinical doctors identify patients with a poor prognosis.

Triplet Energy Gap-Regulated Room Temperature Phosphorescence in Host-guest Doped Systems.

The organic room temperature phosphorescence (RTP) materials via host-guest doped method receive considerable attention in the fields of optoelectronics, bioimaging, and information encryption. Despite many host-guest doped materials with excellent RTP properties have been developed, their luminous mechanism is still limited. Here, a series of host-guest doped materials, using Benzophenone as the host and quinone compounds as the guests, were constructed to investigate the effect of the triplet energy gap (ΔET) between the host and guest on triplet states population. The guest's triplet state is proposed to be a "triplet energy reservoir", gathering the triplet excitons to emit RTP when ΔET is large and returning triplet excitons to the host when ΔET is small. By combining the results of steady-state and delayed emission spectra, time-resolved transient absorption, and theoretical calculations, A bidirectional energy transfer process is proved, which are triplet-triplet energy transfer and reverse triplet-triplet energy transfer processes. The thermal equilibrium of these two energy transfer processes can be regulated by the ΔET and temperature. The potential applications of these RTP properties are also realized in data encryption and anti-counterfeiting. This work provides valuable insight into the design of host-guest doped materials based on energy transfer mechanisms.

A Cohort Study on Deficiency of ADA2 from China.

PURPOSE: Deficiency of adenosine deaminase 2 (DADA2), an autosomal recessive autoinflammatory disorder caused by biallelic loss-of-function variants in adenosine deaminase 2 (ADA2), has not been systemically investigated in Chinese population yet. We aim to further characterize DADA2 cases in China. METHODS: A retrospective analysis of patients with DADA2 identified through whole exome sequencing (WES) at seventeen rheumatology centers across China was conducted. Clinical characteristics, laboratory findings, genotype, and treatment response were analyzed. RESULTS: Thirty patients with DADA2 were enrolled between January 2015 and December 2021. Adenosine deaminase 2 enzymatic activity was low in all tested cases to confirm pathogenicity. Median age of disease presentation was 4.3 years and the median age at diagnosis was 7.8 years. All but one patient presented during childhood and two subjects died from complications of their disease. The patients most commonly presented with systemic inflammation (92.9%), vasculitis (86.7%), and hypogammaglobinemia (73.3%) while one patient presented with bone marrow failure (BMF) with variable cytopenia. Twenty-three (76.7%) patients were treated with TNF inhibitors (TNFi), while two (6.7%) underwent hematopoietic stem cell transplantation (HSCT). They all achieved clinical remission. A total of thirty-nine ADA2 causative variants were identified, six of which were novel. CONCLUSION: To establish early diagnosis and improve clinical outcomes, genetic screening and/or testing of ADA2 enzymatic activity should be performed in patients with suspected clinical features. TNFi is considered as first line treatment for those with vascular phenotypes. HSCT may be beneficial for those with hematological disease or in those who are refractory to TNFi.

Evaluation of belimumab in treatment of Chinese childhood-onset systemic lupus erythematosus: a prospective analysis from multicenter study.

OBJECTIVE: The aim of this study is to identify whether low lupus disease activity status (LLDAS) and clinical remission (CR) of belimumab plus standard of care (SoC) therapy are achievable goals in childhood-onset SLE (cSLE). METHODS: This multicentre, one arm pre-post intervention study was conducted at 15 centers in China. The primary end point was to describe the proportion of patients who achieved LLDAS and CR after 3, 6, and 12 months after treatment with belimumab plus SoC therapy. A multiple regression model was used to impute missing data. A Poisson regression model was used to calculate the effect of belimumab treatment on the reduced risk of serious diseases and the incidence of new damage. RESULT: 193 (92.2% female) with active cSLE from 15 centers were included. At 3, 6 and 12 months, the proportion of LLDAS (CR) was 12.4% (1.0%), 25.6% (4.5%) and 70.3% (29.7%), respectively. The mean SELENA-SLEDAI score decreased from 11.0 at baseline to 3.7, 2.9 and 1.7 at 3, 6, and 12 months. At baseline, all patients received steroids at a mean (SD) prednisone equivalent dose of 31.0 (18.2) mg/day, which decreased to 19.4 (10.8) mg/day at month 3, 12.6 (7.2) mg/day at month 6 and 6.7 (5.3) mg/day at month 12. The symptoms and immunological indicators were also significantly improved. CONCLUSION: This is the first and largest sample size prospective clinical intervention study of cSLE patients treated with belimumab in China. LLDAS and CR were attainable treat-to-target of belimumab plus SoC therapy in cSLE.

Uncovering the substituted-position effect on excited-state evolution of benzophenone-phenothiazine dyads.

Photofunctional materials based on donor-acceptor molecules have drawn intense attention due to their unique optical properties. Importantly, Systematic investigation of substitution effects on excited-state charge transfer dynamics of donor-acceptor molecules is a powerful approach for identifying application-relevant design principles. Here, by coupling phenothiazine (PTZ) at the ortho-, meta-, and para-positions of the benzene ring of benzophenone (BP), three regioisomeric BP-PTZ dyads were designed to understand the relationship between substituted positions and excited-state evolution channels. Ultrafast transient absorption is used to detect and trace the transient species and related evolution channels of BP-PTZ dyads at excited state. In a non-polar solvent, BP-o-PTZ undergoes the through-space charge transfer process to produce a singlet charge-transfer (1CT) state, which subsequently proceeds the intersystem crossing process and transforms into a triplet charge-transfer (3CT) state; BP-m-PTZ experiences intramolecular charge transfer (ICT) process to generate the 1CT state, which subsequently transforms into the 3CT state by the intersystem crossing (ISC) and finally converts into the local-excited triplet (3LE) state; as for BP-p-PTZ, only 3LE states can be detected after the ISC process from the 1CT state. On the other hand, the twisted ICT states are generated via twisted motion between the donor and acceptor for all BP-PTZ dyads or planarization of the PTZ unit in high polar solvents. The excited-state theoretical calculations unveil that the features of ICT and intramolecular interaction between the three dyads play a decisive role in determining the through-bond charge transfer and through-space charge transfer processes. Also, these results demonstrate that the excited-state evolution channels of PTZ derivatives could be modified by tuning the substituted positions of the donor-acceptor dyads. This study provides a deep perspective for the substitute-position effect on donor-acceptor-type PTZ derivatives.

Low-Threshold Blue Quasi-2D Perovskite Laser through Domain Distribution Control.

Quasi-2D perovskites, composed of self-organized quantum well structures, are emerging as gain materials for laser applications. Here we investigate the influence of domain distribution on the laser emission of CsPbCl1.5Br1.5-based quasi-2D perovskites. The use of 2,2-diphenylethylammonium bromide (DPEABr) as a ligand enables the formation of quasi-2D film with a large-n-dominated narrow domain distribution. Due to the reduced content of small-n domains, the incomplete energy transfer from small-n to large-n domains can be greatly addressed. Moreover, the photoinduced carriers can be concentrated on most of the large-n domains to reduce the local carrier density, thereby suppressing the Auger recombination. By controlling the domain distribution, we achieve blue amplified spontaneous emission and single-mode vertical-cavity surface-emitting lasing with low thresholds of 6.5 and 9.2 µJ cm-2, respectively. This work provides a guideline to design the domain distribution to realize low-threshold multicolor perovskite lasers.

Boosting the Optoelectronic Performance by Regulating Exciton Behaviors in a Porous Semiconductive Metal-Organic Framework.

Exciton behaviors including exciton formation and dissociation dynamics play an essential role in the optoelectronic performance of semiconductive materials but remain unexplored in semiconductive metal-organic frameworks (MOFs). Herein, we reveal that the exciton behaviors in semiconductive MOFs can be regulated by framework-guest interactions, a feature often not achievable in traditional inorganic or organic semiconductors. Incorporation of the electron-deficient molecule within the pores of a terbium-based semiconductive MOF (Tb2L2·4H2O·6DMF, L = TATAB3-, 4,4',4″-s-triazine-1,3,5-triyltri-p-aminobenzoate, DMF = N,N-dimethylformamide) results in efficient energy transfer from the MOF skeleton to molecular acceptors, with a yield of up to 77.4%. This interaction facilitates distinctive exciton type conversion, giving rise to modified conductivity and photoelectric performance. We further fabricated a MOF-based X-ray detection device to demonstrate how the new architecture bolsters the optoelectronic efficiency, which outperforms the properties of parent semiconductive MOFs, with more than 60 times and 40 times enhancement of the photocurrent on-off ratio and detection sensitivity, respectively. With judiciously optimized exciton behaviors, the detection device exhibits a high sensitivity of 51.9 µC Gyair-1 cm-2 and records a charge carrier mobility-lifetime product of 1.12 × 10-3 cm2 V-1 among MOF-based X-ray detectors, which are competitive with values for commercially available detectors. These findings demonstrate a rational synthetic approach to designing exciton arrangements to improve the optoelectronic efficiency of semiconductive MOFs.

Ultrafast study of substituted-position-dependent excited-state evolution in benzophenone-carbazole dyads.

Donor and acceptor (D-A) compounds based on benzophenone (BP) and carbazole (Cz) were recently reported to exhibit an extraordinary long afterglow phosphorescence in the solid state. However, the BP derivatives' mechanism of long afterglow phosphorescence is obscure. BP-o-Cz, BP-m-Cz, and BP-p-Cz were designed by coupling Cz at the ortho-, meta- and para-positions of the BP's benzene ring to uncover the excited-state evolution of BP-Cz molecules. Femtosecond and nanosecond transient absorption and excited-state theoretical calculations were carried out to detect and trace the photophysical process of BP-Cz dyads. After the excitation, all dyads experience intramolecular charge transfer (ICT) and intersystem crossing (ISC) processes. The resulting charge-transfer (1CT and 3CT) state of BP-o-Cz will decay to the ground state directly and quickly via the fast charge recombination (CR) process, which may be caused by through-space D-A interaction due to the enforced proximity between BP and Cz. In contrast, for BP-m-Cz and BP-p-Cz dyads, the complete separation of HOMOs and LUMOs leads to extended ICT and slow CR processes, producing an obvious Cz cation radical intermediate and an ultralong-lived triplet state species after the 3CT. Herein, we demonstrated that the excited-state evolution channels could be modified by tuning the substituted positions of D-A dyads. This may pave the way for designing efficient D-A type luminescent materials.

Deficiency in the frequency and function of Tr1 cells in IgAV and the possible role of IL-27.

OBJECTIVE: Type 1 regulatory T (Tr1) cells are involved in the pathogenesis of numerous immune-mediated diseases. However, little is known about whether and how Tr1 cells affect the development of IgA vasculitis (IgAV). We aimed to investigate this question in IgAV patients. METHODS: . Tr1 cells in peripheral blood and kidney tissue of IgAV patients were analysed by multi-parametric flow cytometry and immunofluorescence techniques. An in vitro assay of suppression of T cell proliferation and cytokine release was performed to evaluate the function of Tr1 cells. Real-time PCR and cell stimulation in vitro were used to explore the roles of IL-27 and early growth response gene 2 (EGR2). RESULTS: The frequency of Tr1 cells was decreased in peripheral blood but increased in kidney tissue from IgAV patients. A defective suppressive function of Tr1 cells in IgAV was observed. The frequency of Tr1 cells and the cytokines secreted by them were up-regulated in the presence of recombinant IL-27 in vitro. Moreover, IL-27 also increased the expression of EGR2. Furthermore, lower frequency of Tr1 cells during remission had a higher recurrence rate. CONCLUSION: Tr1 cells are involved in the pathogenesis of IgAV. The low IL-27 in IgAV is responsible for impaired frequency and function of Tr1 cells, and EGR2 may be the specific transcription factor involved in the progression. Tr1 may be a risk factor for IgAV recurrence.

Disentangling Multiple Effects on Excited-State Intramolecular Charge Transfer among Asymmetrical Tripartite PPI-TPA/PCz Triads.

By utilizing the bipolarity of 1,2-diphenylphenanthroimidazole (PPI), two types of asymmetrical tripartite triads (PPI-TPA and PPI-PCz) were designed with triphenylamine (TPA) and 9-phenylcarbazole (PCz). These triads are deep-blue luminescent materials with a high fluorescence quantum yield of nearly 100 %. To trace the photophysical behaviors of these triads, their excited-state evolution channels and interchromophoric interactions were investigated by ultrafast time-resolved transient absorption and excited-state theoretical calculations. The results suggest that the electronic nature, asymmetrical tripartite structure, and electron-hole distance of these triads, as well as solvent polarity, determine the lifetime of intramolecular charge transfer (ICT). Interestingly, PPI-PCz triads show anti-Kasha ICT, and the charge-transfer direction among the triads is adjustable. For the PPI-TPA triad, the electron is transferred from TPA to PPI, whereas for the PPI-PCz triad the electron is pushed from PPI to PCz. Exploration of the excited-state ICT in these triads may pave the way to design better luminescent materials in the future.

Association between alcohol intake and the risk of systemic lupus erythematosus: A systematic review and meta-analysis.

OBJECTIVES: Previous studies have reported inconsistent results on the relationship between alcohol intake and the risk of systemic lupus erythematosus (SLE). Therefore, we conducted a systematic review and meta-analysis to illustrate the potential role of alcohol intake on the progression of SLE. METHODS: An electronic search of the PubMed, EmBase, and the Cochrane library databases was conducted from their inception up to March 2020. Observational studies that investigated the role of alcohol intake on the risk of SLE were eligible for inclusion in this study. The pooled odds ratio (OR) with 95% confidence interval (CI) was calculated as an effect estimate using the random-effects model. RESULTS: Seven case-control studies (n = 3, 251) and three cohort studies (n = 322, 479) were selected for the final meta-analysis. Mild (OR: 0.85; 95% CI: 0.53-1.38; p = 0.515) or heavy (OR: 0.63; 95% CI: 0.37-1.09; p = 0.102) alcohol intake were not associated with the risk of SLE, while moderate alcohol intake could protect against the risk of SLE (OR: 0.71; 95% CI: 0.55-0.93; p = 0.012). Sensitivity analysis suggested that heavy alcohol intake was associated with a reduced risk of SLE (OR: 0.47; 95% CI: 0.32-0.67; p < 0.001). CONCLUSIONS: This study found that moderate alcohol intake could protect against the risk of SLE, while mild or heavy alcohol intake did not significantly affect the risk of SLE.

Inducible nitric oxide synthase and systemic lupus erythematosus: a systematic review and meta-analysis.

BACKGROUND: There is a growing body of evidences indicating iNOS has involved in the pathogenesis of SLE. However, the role of iNOS in SLE is inconsistency. This systematic review was designed to evaluate the association between iNOS and SLE. RESULTS: Six studies were included, reporting on a total of 277 patients with SLE. The meta-analysis showed that SLE patients had higher expression of iNOS at mRNA level than control subjects (SMD = 2.671, 95%CI = 0.446-4.897, z = 2.35, p = 0.019), and a similar trend was noted at the protein level (SMD = 3.602, 95%CI = 1.144-6.059, z = 2.87, p = 0.004) and positive rate of iNOS (OR = 9.515, 95%CI = 1.915-47.281, z = 2.76, p = 0.006) were significantly higher in SLE group compared with control group. No significant difference was observed on serum nitrite level between SLE patients and control subjects (SMD = 2.203, 95%CI = -0.386-4.793, z = 1.64, p = 0.095). The results did not modify from different sensitivity analysis, representing the robustness of this study. No significant publication bias was detected from Egger's test. CONCLUSIONS: There was a positive correlation between increasing iNOS and SLE. However, the source of iNOS is unknown. Besides NO pathway, other pathways also should be considered. More prospective random studies are needed in order to certify our results.

Severe sepsis caused by serious gastrointestinal infection in sJIA patients treated with IL-6 receptor antagonist: a case report.

BACKGROUND: Interleukin (IL)-6 plays an essential role in the pathogenesis of systemic juvenile idiopathic arthritis (sJIA). Tocilizumab (TCZ), a kind of biological agent against both membrane and soluble IL-6 receptor, is the only biological agent approved for the treatment of sJIA in China. Infections are the most common adverse events during TCZ therapy, and most of infections are mild or moderate. Severe sepsis originated from gastrointestinal infection is rarely reported. CASE PRESENTATION: In this article, we reported two 13-year-old sJIA patients who suffered from life-threatening infections after TCZ administration. Within one day, both of them presented rapidly progressive conditions that included fever, abdominal pain, dizziness, diarrhea and vomiting, and laboratory tests showed multi-organ dysfunctions. They were diagnosed with severe sepsis and septic shock that were supposed to be caused by the pathogens from the gastrointestinal tract, and they were eventually rescued by timely treatment. In addition, we also reviewed the literature about serious gastrointestinal infections and sepsis in sJIA patients receiving TCZ therapy. CONCLUSIONS: In summary, for sJIA patients with TCZ therapy, invading pathogens from the gastrointestinal tract can cause an intensely systemic infection that may even be fatal. Therefore, it is essential to pay attention to the gastrointestinal management of sJIA patients as well as remind them of their intestinal hygiene.

CRISPR/cas9 mediated knockout of an intergenic variant rs6927172 identified IL-20RA as a new risk gene for multiple autoimmune diseases.

Genetic variants near the tumor necrosis factor-α-induced protein 3 gene (TNFAIP3) at the chromosomal region 6q23 demonstrated significant associations with multiple autoimmune diseases. The signals of associations have been explained to the TNFAIP3 gene, the most likely causal gene. In this study, we employed CRISPR/cas9 genome-editing tool to generate cell lines with deletions including a candidate causal variant, rs6927172, at 140 kb upstream of the TNFAIP3 gene. Interestingly, we observed alterations of multiple genes including IL-20RA encoding a subunit of the receptor for interleukin 20. Using Electrophoretic mobility shift assay (EMSA), Western blotting, and chromatin conformation capture we characterized the molecular mechanism that the DNA element carrying the variant rs6927172 influences expression of IL-20RA and TNFAIP3 genes. Additionally, we developed a new use of the transcription activator-like effector (TALE) to study the role of the variant in regulating expressions of its target genes. In summary, we generated deletion knockouts that included the candidate causal variant rs6927172 in HEK293T cells provided new evidence and mechanism for IL-20RA gene as a risk factor for multiple autoimmune diseases.

Distinct variations of antibody secreting cells and memory B cells during the course of Kawasaki disease.

BACKGROUND: Both antibody secreting cells (ASCs) and memory B cells are essential for the maintenance of humoral immunity. To date, limit studies have focused on the two populations in Kawasaki disease (KD). To address the status of humoral immunity during KD, our current concentration is on the variations of ASCs and memory B cells, as well as their subsets in both acute and remission stages of KD. METHODS: ASCs were defined as the population with high expressions of CD27 and CD38 among CD3-CD20- lymphocytes. Based on the expression of surface marker CD138 and intracellular marker IgG, ASCs were further divided into two subsets. Memory B cells were characterized by the expressions of IgD, CD27 and IgM, upon which memory B cells were further categorized into CD27 + IgD- (switched memory, Sm), CD27-IgD- (Double negative, DN) and CD27 + IgD + IgM+ (marginal zone, MZ) B cells. Collectively, six populations were analyzed using flow cytometry. The blood samples were collected from KD patients in different stages and healthy controls. RESULTS: In the acute stage, the percentages of ASCs, CD138+ ASCs, and IgG+ ASCs were significantly increased. In contrast, the percentages of memory B cells including Sm and MZ B cells were significantly decreased. Correlation analysis found ASCs positively correlated with the level of serum IgM, whereas MZ B cells not only positively correlated with the level of serum IgG, IgA, and IgM, but also positively correlated with the level of serum complement C3 and C4 and negatively correlated with the value of C-reactive protein (CRP). In the remission stage, the percentages of IgG+ ASCs and MZ B cells were significantly reduced, whereas other subsets presented heterogeneous variations. CONCLUSIONS: Our study provided direct evidence that ASCs contributed to the pathogenesis of KD, and it was the first time to describe the variation of memory B cells in this disease. Among the subsets, only IgG+ ASCs presented a significant increase in the acute stage and decreased after IVIG administration, indicating the involvement of IgG+ ASCs in the inflammation of KD and also suggesting that IVIG played an inhibitory role in the expression of cytoplasmic IgG.

Distribution of distinct subsets of circulating T follicular helper cells in Kawasaki disease.

BACKGROUND: Kawasaki disease (KD) is an acute febrile vasculitis that primarily affects children. Previous studies have shown that both innate and adapt immune systems are involved in the immunopathogenesis of KD. The following study analyzes the distribution of the subsets of Circulating T follicular helper cells (cTfh cells) in KD patients with and without coronary artery lesions (CALs). METHODS: Twenty KD patients and fifteen healthy sex- and age- matched children were enrolled. Patients were divided into two groups depending on CALs. Blood samples were collected respectively before and after intravenous immunoglobulin (IVIG) administration. Circulating Tfh cells were categorized into three subsets by flow cytometry including cTfh1 (CXCR3 + CCR6-), cTfh2 (CXCR3-CCX6-) and cTfh17 (CXCR3-CCR6+) cells in circulating CD3 + CD4 + CXCR5 + CD45RA- T cells. Cytometric bead arrays were used to analyze the level of IFN-γ, IL-4 and IL-17A. RESULTS: We found that frequency of cTfh2 cells was significantly elevated in KD patients before IVIG administration with low expression of cTfh1 cells, where the ratio of cTfh2 + cTfh17/cTfh1 significantly increased. Levels of IFN-γ, IL-4 and IL-17A in KD were significantly higher compared to controls. Further analysis showed that cTfh1 cells were negatively correlated with serum CRP, whereas cTfh2 cells were positively correlated with serum CRP and ESR. Comparison of different groups showed that frequency of cTfh1 cells in CALs+ group were significantly lower compared to CALs- group. In contrast, cTfh2 cells in CALs+ group significantly increased. After IVIG administration, frequency of cTfh2 cells and the ratio significantly decreased while the frequency of cTfh1 cells significantly increased. Meanwhile, all levels of cytokines decreased. CONCLUSIONS: Our data demonstrated that cTfh1 and cTfh2 cells participate in the pathogenesis of KD, and that the two subsets might be associated with CALs.

Variation in IL-21-secreting circulating follicular helper T cells in Kawasaki disease.

OBJECTIVE: Circulating follicular helper T (cTfh) cells are a specialized subset of CD4+ T cells that express the CXC-chemokine receptor 5 (CXCR5). These cells exhibit immune activities by inducing B cell differentiation and proliferation via the secretion of interleukin (IL)-21. Multiple studies have demonstrated that cTfh cells are associated with the progression and severity of numerous diseases. To investigate the role of cTfh cells in the development of Kawasaki disease (KD), we analyzed the distinct subpopulations of cTfh cells and serum IL-21 levels in different phases of KD. METHODS: According to the differential expression of inducible co-stimulator (ICOS) and programmed cell death protein 1 (PD-1), cTfh cells were divided into distinct subsets. We used flow cytometry and flow cytometric bead arrays (CBA) to analyze subsets of CD4+CXCR5+ T cells and serum IL-21 levels. The samples were collected from control subjects and Kawasaki disease patients in the acute and remission phases. RESULTS: In the acute phase (AP), the percentages of ICOShighPD-1high, ICOS+PD-1+, ICOS-PD-1+, CD45RA-IL-21+ cTfh cells and serum IL-21 levels significantly increased. Furthermore, the percentages of ICOShighPD-1high and ICOS+PD-1+ cTfh cells positively correlated with erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) values, whereas the percentage of ICOS-PD-1+ cTfh cells indicated negative correlations. The percentages of ICOS+PD-1+, ICOShighPD-1high and CD45RA-IL-21+ cTfh cells correlated positively with serum IL-21 levels. In the remission phase (RP), the percentages of ICOS-PD-1+, CD45RA-IL-21+ cTfh cells and serum IL-21 levels were significantly decreased. In contrast, the percentages of ICOS+PD-1+, ICOShighPD-1high, and ICOS+PD-1- cTfh cells were further increased. Among these subsets, only CD45RA-IL-21+ cTfh cells correlated positively with serum IL-21 levels. CONCLUSIONS: The present study is the first investigation that examined the distribution of circulating cTfh cell subsets in Kawasaki disease. Both cTfh cells and serum IL-21 are essential to the pathogenesis of KD. Our study provides further understanding of the immune response involved in KD and offers novel insights in the pathogenetic mechanism of this disease.

Distinct phenotypic subpopulations of circulating CD4+CXCR5+ follicular helper T cells in children with active IgA vasculitis.

BACKGROUND: Circulating follicular helper T (Tfh) cells are a heterogeneous population of CD4+ helper T cells that promotes pathogenic immune responses in autoimmune diseases. In this study, we examined the status of different subpopulations of Tfh cells in peripheral circulation and their associations with various clinical characteristics of IgA vasculitis (IgAV). METHODS: According to the phenotypic expressions of different molecules, focus was given on six subpopulations of Tfh cells: CD4+CXCR5+, CD4+CXCR5+ICOS+, CD4+CXCR5+ICOS+PD-1+, CD4+CXCR5+ICOShighPD-1high, CD4+CXCR5+ICOS-PD-1+, and CXCR5+CD45RA-IL-21+. The frequencies of these six subpopulations and the circulating level of Tfh-related cytokine interleukin 21 (IL-21) were measured from 27 patients with IgAV and 15 healthy controls (HC) by flow cytometry and flow cytometric bead array, respectively. RESULTS: Significantly higher frequencies of CD4+CXCR5+, CD4+CXCR5+ICOS+, CD4+CXCR5+ICOS+PD-1+, CD4+CXCR5+ICOShighPD-1high and CXCR5+CD45RA-IL-21+ Tfh cells, as well as higher levels of plasma IL-21, were detected in IgAV patients compared to HC. The level of each Tfh subpopulation varied by the presenting symptoms of IgAV, but did not differ between patients treated or not treated with glucocorticoids. When the disease entered the remission stage following treatment, circulating levels of CD4+CXCR5+, CD4+CXCR5+ICOS+, CD4+CXCR5+ICOS+PD-1+, CD4+CXCR5+ICOShighPD-1high and CXCR5+CD45RA-IL-21+ Tfh cells, as well as plasma IL-21 levels were reduced. Among the six subpopulations of Tfh cells, both CD4+CXCR5+ICOS+ and CXCR5+CD45RA-IL-21+ significantly and positively correlated with serum IgA and plasma IL-21 levels, but only CXCR5+CD45RA-IL-21+ significantly and negatively correlated with the serum C4 level. CONCLUSIONS: Tfh cells may differentially contribute to the development of IgAV or predict disease progression. These findings provide novel insights in the pathogenesis of IgAV and may benefit treatment development targeting organ-specific presenting symptoms of IgAV.

Intermittent pulses of methylprednisolone with low-dose prednisone attenuate lupus symptoms in B6.MRL-Faslpr/J mice with fewer glucocorticoid side effects.

Glucocorticoids (GCs) are potent anti-inflammatory and immunosuppressant medications and remain the cornerstone of systemic lupus erythematosus (SLE) therapy. However, ongoing exposure to GCs has the potential to elicit multiple adverse effects. Considering the irreplaceability of GCs in SLE therapy, it is important to explore the optimal regimen of GCs. Here, we compared the long-term efficacy and safety of pulsed and oral GC therapy in a lupus-prone mouse model. Mice were grouped using a randomized block design. We monitored survival rates, proteinuria, serum autoantibodies, and complement 3 (C3) levels up to 28 weeks of age, and assessed renal damage, bone quality, lipid deposition in the liver and marrow, glucose metabolic parameters, and levels of hormones of the hypothalamic-pituitary-adrenal (HPA) axis. Finally, we explored the mechanisms underlying the superior efficacy of the pulse regimen over oral prednisone regimen. We found that both GC regimens alleviated the poor survival rate, proteinuria, and glomerulonephritis, while also reducing serum autoantibodies and increasing the level of C3. The pulsed GC regimen showed less resistance to insulin, less suppression of the HPA axis, less bone loss, and less bone marrow fat deposition than the oral GC regimen. Additionally, GC-induced leucine zipper (GILZ) was significantly overexpressed in the GC pulse group. These results suggest that the GC pulse regimen ameliorated symptoms in lupus-prone mice, with fewer side effects, which may be related to GILZ overexpression. Our findings offer a potentially promising GC treatment option for SLE.