Role of serum complement C3 and C4 on kidney outcomes in IgA nephropathy.

IgA Nephropathy (IgAN) is the most prevalent glomerular disease worldwide. Complement system activation is crucial in its pathogenesis. Few studies correlated serum C3 and C4 with disease activity and prognosis. This retrospective study investigated the prognostic value of serum complement at the time of diagnosis in patients with IgAN. Specifically we evaluated whether adding serum C3 and C4 levels to established predictive models-one based on variables related to chronic kidney disease (CKD) progression and another incorporating variables from the International IgA Prediction Tool (IntIgAPT)-enhances the accuracy of outcome prediction. A composite renal outcome was defined as 50% decline in eGFR or onset of kidney failure. 101 patients were stratified according to baseline C3 levels in three groups (Low, Medium and High). During a median follow-up of 54 months, the Low group exhibited higher incidence of primary outcome (16.3 events vs 2.9 and 1.7 events × 100 pts/year, p = 0.0026). Model-1 (M1), consisting of CKD progression variables, and Model-3 (M3), comprising IntIgANPT variables, were implemented with baseline C3 and C4 to create Model-2 (M2) and Model-4 (M4), respectively. M2 demonstrated better predictive performance over M1, showing higher discrimination (lower AIC and BIC, higher C-index and NR2). Similarly, M4 outperformed M3, showing enhanced outcome prediction when C3 and C4 levels were added. Implementation of serum C3 and C4 can enhance prediction accuracy of already-validated prognostic models in IgAN. Lower C3 and higher C4 levels were associated with poorer prognosis, highlighting a more 'Complement-Pathic' subset of patients.

Albumin to globulin ratio (AGR) in systemic lupus erythematosus: correlation with disease activity.

OBJECTIVE: To investigate the role of albumin-to-globulin ratio (AGR) in systemic lupus erythematosus (SLE) and its relationship with disease activity. METHODS: This retrospective study consecutively selected patients with SLE and healthy controls. Patients were divided into three groups according to the SLE Disease Activity Index 2000 (SLEDAI-2K): group 1 (mild disease activity, SLEDAI-2K ≤ 6), group 2 (moderate disease activity, SLEDAI-2K 7-12) and group 3 (severe disease activity, SLEDAI-2K > 12). Predictors of SLE disease activity were analysed by ordinal logistical regression. RESULTS: A total of 101 Chinese patients with SLE and 75 healthy Chinese controls were included. Patients with SLE had lower AGR values than healthy individuals, and group 3 patients with SLE displayed lower AGR values than those in group 1, but similar values to group 2. AGR was inversely correlated with SLEDAI-2K (r = -0.543). Ordinal logistic regression analysis showed that lower AGR (ß = -1.319) and lower complement C4 (ß = -1.073) were independent risk factors for SLE disease activity. CONCLUSIONS: AGR was decreased in patients with SLE and may be utilized as a useful inflammatory biomarker for monitoring SLE disease activity.

Serum concentrations of complement C3 and C4 in dogs with idiopathic epilepsy.

BACKGROUND: High concentrations of complement factors are presented in serum of animal epilepsy models and human patients with epilepsy. OBJECTIVES: To determine whether complement dysregulation occurs in dogs with idiopathic epilepsy (IE). ANIMALS: The study included 49 dogs with IE subgrouped into treatment (n = 19), and nontreatment (n = 30), and 29 healthy dogs. METHODS: In this case-control study, the serum concentrations of the third (C3) and fourth (C4) components of the complement system were measured using a canine-specific ELISA kit. RESULTS: Serum C3 and C4 concentrations were significantly higher in dogs with IE (C3, median; 4.901 [IQR; 3.915-6.673] mg/mL, P < .001; C4, 0.327 [0.134-0.557] mg/mL, P = .03) than in healthy control dogs (C3, 3.550 [3.075-4.191] mg/mL; C4, 0.267 [0.131-0.427] mg/mL). No significant differences were observed in serum C3 and C4 concentrations between dogs in the treatment (C3, median; 4.894 [IQR; 4.192-5.715] mg/mL; C4, 0.427 [0.143-0.586] mg/mL) and nontreatment groups (C3, 5.051 [3.702-7.132] mg/mL; C4, 0.258 [0.130-0.489] mg/mL). Dogs with a seizure frequency >3 times/month had significantly higher serum C3 (6.461 [4.695-8.735] mg/mL; P < .01) and C4 (0.451 [0.163-0.675] mg/mL; P = .01) concentrations than those with a seizure frequency ≤3 times/month (C3, 3.859 [3.464-5.142] mg/mL; C4, 0.161 [0.100-0.325] mg/mL). CONCLUSIONS AND CLINICAL IMPORTANCE: Dysregulation of classical complement pathway was identified in IE dogs. Serum C3 and C4 concentrations could be diagnostic biomarkers for IE in dogs with higher seizure frequency.

The Complement Component 4 Binding Protein α Gene: A Versatile Immune Gene That Influences Lipid Metabolism in Bovine Mammary Epithelial Cell Lines.

Complement component 4 binding protein α (C4BPA) is an immune gene which is responsible for the complement regulation function of C4BP by binding and inactivating the Complement component C4b (C4b) component of the classical Complement 3 (C3) invertase pathway. Our previous findings revealed that C4BPA was differentially expressed by comparing the transcriptome in high-fat and low-fat bovine mammary epithelial cell lines (BMECs) from Chinese Holstein dairy cows. In this study, a C4BPA gene knockout BMECs line model was constructed via using a CRISPR/Cas9 system to investigate the function of C4BPA in lipid metabolism. The results showed that levels of triglyceride (TG) were increased, while levels of cholesterol (CHOL) and free fatty acid (FFA) were decreased (p < 0.05) after knocking out C4BPA in BMECs. Additionally, most kinds of fatty acids were found to be mainly enriched in the pathway of the biosynthesis of unsaturated fatty acids, linoleic acid metabolism, fatty acid biosynthesis, and regulation of lipolysis in adipocyte. Meanwhile, the RNA-seq showed that most of the differentially expressed genes (DEGs) are related to PI3K-Akt signaling pathway. The expressions of 3-Hydroxy-3-Methylglutaryl-CoA Synthase 1 (HMGCS1), Carnitine Palmitoyltransferase 1A (CPT1A), Fatty Acid Desaturase 1 (FADS1), and Stearoyl-Coenzyme A desaturase 1 (SCD1) significantly changed when the C4BPA gene was knocked out. Collectively, C4BPA gene, which is an immune gene, played an important role in lipid metabolism in BMECs. These findings provide a new avenue for animal breeders: this gene, with multiple functions, should be reasonably utilized.

Molecular Interactions Required for Activation of Complement Component C2 Include Exosites Located on the Serine Protease Domain of C1s and Mannose-Binding Lectin Associated Protease-2.

The activation of the CP/LP C3 proconvertase complex is a key event in complement activation and involves cleavage of C4 and C2 by the C1s protease (classical pathway) or the mannose-binding lectin-associated serine protease (MASP)-2 (lectin pathway). Efficient cleavage of C4 by C1s and MASP-2 involves exosites on the complement control protein and serine protease (SP) domains of the proteases. The complement control protein domain exosite is not involved in cleavage of C2 by the proteases, but the role of an anion-binding exosite (ABE) on the SP domains of the proteases has (to our knowledge) never been investigated. In this study, we have shown that the ABE on the SP of both C1s and MASP-2 is crucial for efficient cleavage of C2, with mutant forms of the proteases greatly impaired in their rate of cleavage of C2. We have additionally shown that the site of binding for the ABE of the proteases is very likely to be located on the von Willebrand factor domain of C2, with the precise area differing between the enzymes: whereas C1s requires two anionic clusters on the von Willebrand factor domain to enact efficient cleavage of C2, MASP-2 apparently only requires one. These data provide (to our knowledge) new information about the molecular determinants for efficient activation of C2 by C1s and MASP-2. The enhanced view of the molecular events underlying the early stages of complement activation provides further possible intervention points for control of this activation that is involved in a number of inflammatory diseases.

Complement components regulates ferroptosis in CVB3 viral myocarditis by interatction with TFRC.

BACKGROUND: Dysregulated cell death machinery and an excessive inflammatory response in Coxsackievirus B3(CVB3)-infected myocarditis are hallmarks of an abnormal host response. Complement C4 and C3 are considered the central components of the classical activation pathway and often participate in the response process in the early stages of virus infection. METHODS: In our study, we constructed a mouse model of CVB3-related viral myocarditis via intraperitoneal injection of Fer-1 and detected myocarditis and ferroptosis markers in the mouse myocardium. Then, we performed co-IP and protein mass spectrometry analyses to explore which components interact with the ferroptosis gene transferrin receptor (TFRC). Finally, functional experiments were conducted to verify the role of complement components in regulating ferroptosis in CVB3 infection. RESULTS: It showed that the ferroptosis inhibitor Fer-1 could alleviate the inflammation in viral myocarditis as well as ferroptosis. Mechanistically, during CVB3 infection, the key factor TFRC was activated and inhibited by Fer-1. Fer-1 effectively prevented the consumption of complement C3 and overload of the complement product C4b. Interestingly, we found that TFRC directly interacts with complement C4, leading to an increase in the product of C4b and a decrease in the downstream complement C3. Functional experiments have also confirmed that regulating the complement C4/C3 pathway can effectively rescue cell ferroptosis caused by CVB3 infection. CONCLUSIONS: In this study, we found that ferroptosis occurs through crosstalk with complement C4 in viral myocarditis through interaction with TFRC and that regulating the complement C4/C3 pathway may rescue ferroptosis in CVB3-infected cardiomyocytes.

Soluble terminal complement complex blood levels are elevated in schizophrenia.

The role of the complement system in schizophrenia (Sz) is inconclusive due to heterogeneity of the disease and study designs. Here, we assessed the levels of complement activation products and functionality of the classical pathway in acutely ill unmedicated Sz patients at baseline and after 6 weeks of treatment versus matched controls. The study included analyses of the terminal complement complex (sTCC) and C5a in plasma from 96 patients and 96 controls by enzyme-linked immunosorbent assay. Sub-group analysis of serum was conducted for measurement of C4 component and activity of the classical pathway (28 and 24 cases per cohort, respectively). We found no differences in levels of C5a, C4 and classical pathway function in patients versus controls. Plasma sTCC was significantly higher in patients [486 (392-659) ng/mL, n = 96] compared to controls [389 (304-612) ng/mL, n = 96] (p = 0.027, δ = 0.185), but not associated with clinical symptom ratings or treatment. The differences in sTCC between Sz and controls were confirmed using an Aligned Rank Transformation model considering the covariates age and sex (p = 0.040). Additional analysis showed that sTCC was significantly associated with C-reactive protein (CRP; p = 0.006). These findings suggest that sTCC plays a role in Sz as a trait marker of non-specific chronic immune activation, as previously described for CRP. Future longitudinal analyses with more sampling time points from early recognition centres for psychoses may be helpful to better understand the temporal dynamics of innate immune system changes during psychosis development.

Evaluation of serum complement C4 among COVID-19 patients in Khartoum state: a case control-based study.

Background: The complement system is made up of an abundance of unique plasma proteins that play an important role in innate immunity and inflammation, aiding in the fight against pathogenic microbes and viral diseases. The purpose of this study was to evaluate the serum complement C4 concentration in COVID-19 patients in Khartoum and compare them to healthy controls. Methods: A total of 100 samples were collected, 50 samples from COVID-19 patients who presented as cases and 50 samples from people who were evidently healthy. Overall, 33 (66%) the patient populations in the case group were not in the hospital's intensive care unit (ICU), compared to 17 (34%) who were. The concentrations of C4 in each serum sample were calculated in milligrams per deciliter. SPSS version (20) was used to analyze the data. Results: The means level of complement C4 (mg/dL) were 37.44 ±18.618, 23.90 ±10.229 in the case group and in the control group, respectively. There was a statistically significant difference in complement C4 level between case and control (p-values ≤0.01). In addition, the mean complement C4 level in the ICU and non-ICU case groups was 25.00±17.85 and 43.85±15.712 mg/dL, respectively. There was a statistically significant variance in complement C4 level between ICU and non-ICU (p-values ≤0.01). Furthermore, the cases were divided into four age groups: 20-40, 40-60, 60-80, and over 80 years old. The one-way ANOVA test showed no statistically significant differences between age categories in complement C4 level (P = 0.735) Conclusions: The case group had a higher mean level of complement C4 than the control group, which could be understood by the stimulation of the complement cascade during the COVID-19 illness. Furthermore, the complement C4 level in severe COVID-19 patients was lower than in non-severe COVID-19.

Variations of C3 and C4 Before and During Pregnancy in Systemic Lupus Erythematosus: Association With Disease Flares and Obstetric Outcomes.

OBJECTIVE: To analyze complement level variations in systemic lupus erythematosus (SLE) pregnancies, focusing on disease flares and obstetric complications. METHODS: SLE pregnancies prospectively followed by multidisciplinary teams from 1987 to 2018 in 2 Italian rheumatology centers were retrospectively analyzed. As reference, pregnancy-modified ranges of normal levels of C3 and C4 were derived from 175 pregnancies from the general obstetric population (GOP), as previously described by our group. RESULTS: Two hundred forty-six pregnancies in 172 patients with SLE were analyzed. Eighty-nine percent were live births. Thirty-five flares were recorded in 30 pregnancies (12.2%) and obstetric complications occurred in 47 pregnancies (19.1%) including 27 pregnancy losses, 11 severely preterm births (2 resulting in perinatal death), and 15 hypertensive disorders. C3 and C4 levels were higher in the GOP than in patients with SLE, at any time point. C3 and C4 levels progressively increased during pregnancy in both GOP and SLE pregnancies without flare and obstetric complications, whereas this physiological increase was not observed in pregnancies with flares or obstetric complications. A significantly higher frequency of low C4 was found in pregnancies with flares (at preconception and in each trimester) and preterm births (at preconception). In multivariate analysis, low C4 at preconception was associated with flares (odds ratio 13.81, 95% CI 3.10-61.43, P < 0.001). CONCLUSION: Low C4 at preconception was found to be an independent risk factor for SLE flare during pregnancy. Not only C3 and C4 levels but also their variations should be observed, as their failure to increase can be useful to predict risk of complications and suggest closer monitoring.

HMGB1 cleavage by complement C1s and its potent anti-inflammatory product.

Complement C1s association with the pathogenesis of several diseases cannot be simply explained only by considering its main role in activating the classical complement pathway. This suggests that non-canonical functions are to be deciphered for this protease. Here the focus is on C1s cleavage of HMGB1 as an auxiliary target. HMGB1 is a chromatin non-histone nuclear protein, which exerts in fact multiple functions depending on its location and its post-translational modifications. In the extracellular compartment, HMGB1 can amplify immune and inflammatory responses to danger associated molecular patterns, in health and disease. Among possible regulatory mechanisms, proteolytic processing could be highly relevant for HMGB1 functional modulation. The unique properties of HMGB1 cleavage by C1s are analyzed in details. For example, C1s cannot cleave the HMGB1 A-box fragment, which has been described in the literature as an inhibitor/antagonist of HMGB1. By mass spectrometry, C1s cleavage was experimentally identified to occur after lysine on position 65, 128 and 172 in HMGB1. Compared to previously identified C1s cleavage sites, the ones identified here are uncommon, and their analysis suggests that local conformational changes are required before cleavage at certain positions. This is in line with the observation that HMGB1 cleavage by C1s is far slower when compared to human neutrophil elastase. Recombinant expression of cleavage fragments and site-directed mutagenesis were used to confirm these results and to explore how the output of C1s cleavage on HMGB1 is finely modulated by the molecular environment. Furthermore, knowing the antagonist effect of the isolated recombinant A-box subdomain in several pathophysiological contexts, we wondered if C1s cleavage could generate natural antagonist fragments. As a functional readout, IL-6 secretion following moderate LPS activation of RAW264.7 macrophage was investigated, using LPS alone or in complex with HMGB1 or some recombinant fragments. This study revealed that a N-terminal fragment released by C1s cleavage bears stronger antagonist properties as compared to the A-box, which was not expected. We discuss how this fragment could provide a potent brake for the inflammatory process, opening the way to dampen inflammation.

Quantification of extracellular matrix remodeling for the non-invasive identification of graft fibrosis after liver transplantation.

Detecting patients with early post-transplant fibrosis after liver transplantation (LT) is very important. Non-invasive tests are needed to avoid liver biopsies. We aimed to detect fibrosis in liver transplant recipients (LTR) using extracellular matrix (ECM) remodeling biomarkers. ECM biomarkers for type III (PRO-C3), IV (PRO-C4), VI (PRO-C6) and XVIII (PRO-C18L) collagen formation and type IV collagen degradation (C4M) were measured by ELISA in prospectively collected, cryopreserved plasma samples (n = 100) of LTR with paired liver biopsies from a protocol biopsy program. Fibrosis ≥ F2 was present in 29% of patients (median 44 months post-LT). APRI and FIB-4 neither identified significant fibrosis nor were correlated with histopathological fibrosis scores, while ECM biomarkers (AUCs 0.67-0.74) did. The median levels of PRO-C3 (15.7 vs. 11.6 ng/ml; p = 0.002) and C4M (22.9 vs. 11.6 ng/ml; p = 0.006) levels were elevated in T-cell-mediated rejection compared to normal graft function. The median levels of PRO-C4 (178.9 vs. 151.8 ng/ml; p = 0.009) and C4M (18.9 vs. 16.8 ng/ml; p = 0.004) levels were increased if donor-specific antibodies were present. PRO-C6 had the highest sensitivity (100%), NPV (100%) and negative likelihood-ratio (0) for graft fibrosis. To conclude, ECM biomarkers are helpful in identifying patients at risk of relevant graft fibrosis.

Genome stability­related lncRNA ZFPM2­AS1 promotes tumor progression via miR­3065­5p/XRCC4 in hepatocellular carcinoma.

Long noncoding RNAs (lncRNAs) have a certain link to genomic stability (GS). However, the regulatory relationship of lncRNAs and GS has not been thoroughly investigated in hepatocellular carcinoma (HCC). In the present study, samples were retrieved from The Cancer Genome Atlas with somatic mutations and lncRNA expression data. Cox regression analysis was used to identify independent prognostic factors. The RNA levels were determined by reverse transcription­quantitative PCR and protein levels were detected by western blot analysis. Cell Counting Kit­8 and colony­formation assays were used to assess cell viability. Cell migration was measured by wound­healing and Transwell assays. Cell apoptosis and cell­cycle progression were evaluated by flow cytometry. GS was detected by alkaline comet and chromosomal aberration assays. A xenograft model and lung metastasis model were used to assess the role of zinc finger protein, FOG family member 2 antisense 1 (ZFPM2­AS1) in tumor growth in vivo. The molecular mechanisms underlying the biological functions of ZFPM2­AS1 were investigated through bioinformatics prediction, RNA pull­down and luciferase reporter assays. A total of 85 genomic instability­related lncRNAs were identified and a prognostic model was developed. The prognostic model exhibited good predictive power (area under the receiver operating characteristic curve, 0.786). ZFPM2­AS1 was significantly upregulated in tumor tissues (P<0.001) and it promoted DNA damage repair (P<0.01) and tumor progression in vitro and in vivo. Luciferase reporter assays demonstrated that miR­3065­5p was able to bind directly with ZFPM2­AS1 and X­ray repair cross complementing 4 (XRCC4). ZFPM2­AS1 upregulated XRCC4 expression by acting as a sponge (P<0.001). In the present study, a prognostic model for HCC was developed and validated, and one lncRNA of its components was experimentally investigated. ZFPM2­AS1 regulates XRCC4 by sponging miR­3065­5p to promote GS and HCC progression.

Altered Circulating Follicular T Helper Cell Subsets and Follicular T Regulatory Cells Are Indicators of a Derailed B Cell Response in Lupus, Which Could Be Modified by Targeting IL-21R.

Systemic lupus erythematosus (SLE) is characterized by the breakdown of self-tolerance, the production of high-affinity pathogenic autoantibodies and derailed B cell responses, which indicates the importance of central players, such as follicular T helper (TFH) subsets and follicular T regulatory (TFR) cells, in the pathomechanism of the disease. In this study, we aimed to analyze the distribution of the circulating counterparts of these cells and their association with disease characteristics and B cell disproportions in SLE. We found that the increased percentage of activated circulating TFH (cTFH) and cTFR cells was more pronounced in cutaneous lupus; however, among cTFH subsets, the frequency of cTFH17 cells was decreased in patients with lupus nephritis. Furthermore, the decreased proportion of cTFH17 cells was associated with low complement C4 levels and high disease activity scores. We also investigated whether the blocking of the IL-21 receptor (IL-21R) with an anti-IL-21R monoclonal antibody inhibits the B cell response, since IL-21 primarily produced by TFH cells potentially promotes humoral immunity. We observed that anti-IL-21R inhibited plasmablast generation and immunoglobulin production. Our study demonstrated that, besides cTFR/cTFH imbalance, cTFH17 cells play a crucial role in SLE pathogenesis, and modulating cTFH-B cell interaction through the IL-21/IL-21R pathway may be a promising therapeutic strategy to suppress the pathological B cell response.

Exposure to nitrate induces alterations in blood parameter responses, liver immunity, and lipid metabolism in juvenile turbot (Scophthalmus maximus).

Nitrate (NO3-) pollution of waterbodies has attracted significant global attention as it poses a serious threat to aquatic organisms and human beings. This study aimed to evaluate the role of NO3-, an end product of biological nitrification processes, in immune status and lipid metabolism to have a comprehensive understanding of its toxic effects on fishes. Therefore, in this work, juvenile turbot (Scophthalmus maximus) were subjected to four nominal concentrations of NO3- (i.e., 0, 50, 200, 400 mg/L of NO3--N) for a 60-day period. The results indicated that increased exposure to NO3- (200 and/or 400 mg/L) enhanced the concentrations of plasma heat shock protein concentrations (HSP70), complement component 3 (C3), complement component 4 (C4), immunoglobulin M (IgM) and lysozyme (LYS), which meant that NO3-caused fluctuations in the plasma immune system. Higher exposure to NO3- (200 and/or 400 mg/L) also caused significant enhancements in plasma glutamic pyruvic transaminase (GPT), as well as glutamic oxaloacetic transaminase (GOT) activity. Furthermore, NO3- exposure resulted in upregulation of liver TNF-α, IL-1ß, HSP70, HSP90, and LYS. Additionally, the results suggested that NO3-exposure caused a certain degree of histological damage and inflammation in the liver and activated the immune defense processes of juvenile turbot. Furthermore, the mRNA expression levels of certain genes associated with lipid metabolism (peroxisome proliferator-activated receptor-alpha [PPAR-α], carnitine palmitoyltransferase 1[CPT1], liver X receptor [LXR] together with sterol regulatory element binding protein-1 [SREBP-1]) increased significantly within fish liver exposed to 200/400 mg/L NO3--N treatments. Finally, the results obtained from the analysis of the integrated biological responses version 2 (IBRv2) also confirmed the toxic effects of NO3- on juvenile turbot. According to these findings, it can be found that NO3- emission in the aquatic environment needs to be strictly controlled, as it may cause immune and lipid metabolism disorders in fish.

Effects of dietary threonine on growth and immune response of oriental river prawn (Macrobrachium nipponense).

A 70-day feeding trial was conducted to ascertain the effects of threonine on immune response of juvenile oriental river prawn (Macrobrachium nipponense). Six isonitrogen and isolipidic feeds were formulated according to levels of dietary threonine (0.35%, 0.79%, 1.18%, 1.67%, 2.08% and 2.48% respectively). The juvenile prawns were divided into six groups with four replicates, and stocked into 24 tanks with 50 prawns per tank (initial weight 0.20 ± 0.02 g). The results showed a significant increasing trend of final body weight, specific growth rate, protein efficiency ratio, and weight gain rate when threonine levels increased to 1.67% (P < 0.05). However, feed intake, feed conversion ratio, and whole-body lipid composition significantly decreased as threonine levels in the feed increased up to 1.67% (P < 0.05). Moreover, haemolymph N-urea content was significantly lowest at 1.67% threonine level (P < 0.05), whereas glucose was highest at 0.79% followed by 1.67% of threonine levels in the feeds. Aspartate aminotransferase (AST) enzyme activities were significantly decreased by an imbalance (except 1.67%) of threonine in the feed (P < 0.05). Activities of Alanine aminotransferase (ALT) and albumen (ALB) were not significantly affected by threonine in the feed (P > 0.05). Excessive dietary threonine level (2.48%) significantly activated haemolymph catalase (CAT) activity (P < 0.05), whereas malondialdehyde (MDA) content was significantly affected by deficient (0.35% and 0.79%) dietary threonine levels (P < 0.05). Inducible nitric oxide synthase (iNOS) activity and haemolymph complement component 4 (C4) content were significantly decreased by deficient levels of threonine in the feed (P < 0.05). Excess threonine concentration significantly down-regulated Toll, Dorsal, Relish, and heat shock protein 60 (Hsp60) gene expressions in the hepatopancreas of M. nipponense (P < 0.05), while all genes were significantly up-regulated by the optimal (1.67%) threonine level (P < 0.05). The threonine level at which maximum specific growth rate of M. nipponense occurred was estimated by second degree polynomial regression analysis as 1.65% of threonine level, equivalent to 4.44% dry weight bases of protein in the feed.

Association of complement component 4 with neuroimmune abnormalities in the subventricular zone in schizophrenia and autism spectrum disorders.

An early inflammatory insult is the most recognized risk factor associated with neurodevelopmental psychiatric disorders, even more so than genetic variants. Notably, complement component 4 (C4), a molecule involved in inflammatory responses, has been strongly associated with schizophrenia (SZ) and its role in other neurodevelopmental disorders, such as autism (ASD), is an area of active investigation. However, while C4 in SZ has been implicated in the context of synaptic pruning, little is known about its neuroinflammatory role. The subventricular zone (SVZ) is a region heavily involved in neurodevelopment and neuroimmune interactions through the lifespan; thus, it is a region wherein C4 may play a vital role in disease pathology. Using in situ hybridization with radioactive riboprobes and RNAscope, we identified robust astrocytic expression of C4 in the SVZ and in the septum pellucidum. C4 was also expressed in ependyma, neurons, and Ki67+ progenitor cells. Examination of mRNA levels showed elevated C4 in both ASD and SZ, with higher expression in SZ compared to controls. Targeted transcriptomic analysis of inflammatory pathways revealed a strong association of complement system genes with SZ, and to a lesser extent, ASD, as well as generalized immune dysregulation without a strong association with known infectious pathways. Analysis of differentially expressed genes (DEGs) showed that ASD DEGs were enriched in adaptive immune system functions such as Th cell differentiation, while SZ DEGs were enriched in innate immune system functions, including NF-κB and toll like receptor signaling. Moreover, the number of Ki67+ cells was significantly higher in ASD compared to SZ and controls. Taken together, these results support a role for C4 into inflammatory-neuroimmune dysregulation observed in SZ and ASD pathology.

Serological Biomarkers of Extracellular Matrix Turnover and Neutrophil Activity Are Associated with Long-Term Use of Vedolizumab in Patients with Crohn's Disease.

Crohn's disease (CD) is a relapsing-remitting inflammatory disease of the gastrointestinal (GI) tract characterized by increased extracellular matrix (ECM) remodeling. The introduction of the α4ß7-integrin inhibitor vedolizumab (VEDO) has improved disease management, although there is a high rate of primary non-response in patients with CD. We studied whether ECM biomarkers of neutrophil activity and mucosal damage could predict long-term response to VEDO in patients with CD. Serum levels of human neutrophil elastase (HNE)-derived fragments of calprotectin (CPa9-HNE), and matrix metalloproteinase (MMP)-derived fragments of type I (C1M), III (C3M), IV (C4M), and VI (C6Ma3) collagen, type III collagen formation (PRO-C3), basement membrane turnover (PRO-C4) and T-cell activity (C4G), were measured using protein fingerprint assays in patients with CD (n = 32) before VEDO therapy. Long-term response was defined as VEDO treatment of at least 12 months. CPa9-HNE was significantly increased at baseline in non-responders compared with responders (p < 0.05). C1M, C3M, C4M, C6Ma3, and PRO-C4 were also significantly increased at baseline in non-responders compared with responders (all p < 0.05). All biomarkers were associated with response to VEDO (all p < 0.05). To conclude, baseline levels of serum biomarkers for neutrophil activity and mucosal damage are linked to the pathology of CD, and are associated with long-term use of VEDO in patients with CD. Therefore, these biomarkers warrant further validation and could aid in therapeutic decision-making concerning vedolizumab therapy.

Plasma Complement 3 and Complement 4 Are Promising Biomarkers for Distinguishing NMOSD From MOGAD and Are Associated With the Blood-Brain-Barrier Disruption in NMOSD.

Background and Objective: Neuromyelitis optica spectrum disorders (NMOSD) and myelin oligodendrocyte glycoprotein antibody (MOG-IgG) associated disease (MOGAD) are autoimmune inflammatory demyelinating diseases of the central nervous system (CNS). As the clinical features of NMOSD are similar to MOGAD, diagnostic confusion exists between the two diseases. To better discriminate NMOSD from MOGAD, we investigated whether the plasma levels of complement 3 (C3) and complement 4 (C4) are different in NMOSD and MOGAD during the acute attacks of the diseases. We sought to determine whether C3 or C4 has an influence on the features of NMOSD. Methods: In this observational study, data from 73 aquaporin-4 antibodies (AQP4-IgG) positive NMOSD patients and 22 MOG-IgG positive MOGAD patients were collected retrospectively. Demographics, clinical characteristics, plasma parameters, and cerebrospinal fluid (CSF) findings will be analyzed for comparability between the two groups. Immunoglobulin-G (IgG) and albumin were measured in both plasma and CSF. Plasma levels of C3 and C4 were measured and compared between the NMOSD, MOGAD, and 42 healthy controls (HC). The correlations between plasma C3, C4, and NMOSD clinical parameters were analyzed. Results: The ages of onset were later in the AQP4-IgG positive NMOSD group and females predominated, which differed from the MOGAD group, whose ages were younger and with a slight male preponderance. The AQP4-IgG positive NMOSD patients presented with the clinical symptoms of optic neuritis (ON) and transverse myelitis (TM), whereas encephalitis symptoms were more prevalent in MOGAD patients. CSF analysis shows that slight but not significantly higher white cell count (WCC) and protein were observed in the MOGAD group than in the AQP4-IgG positive NMOSD group. The plasma levels of IgG in MOGAD patients are significantly lower (p = 0.027) than in NMOSD patients. On the contrary, the plasma levels of albumin in MOGAD were higher than in NMOSD, which reached statistical significance (p = 0.039). Both the plasma C3 and C4 levels in the NMOSD group were significantly lower than in MOGAD and HC. The receiver operating characteristic (ROC) curve of the prediction model comprises C3 and C4 to distinguish NMOSD from MOGAD [area under the curve (AUC): 0.731, 0.645], which are considered to have discriminatory values. The results of Spearman's analysis revealed that there was a significant positive correlation between the plasma C3 and the CSF WCC (r = 0.383, p = 0.040). There was an inverse correlation between plasma C4 and plasma IgG (r = -0.244, p = 0.038). Plasma C3 or C4 was significantly positively correlated with CSF albumin and Q-Alb, which is considered a measure of blood-brain barrier (BBB) disruption. Conclusion: During the acute phase of NMOSD and MOGAD, plasma C3 and C4 may become potential biomarkers for distinguishing the two diseases and reflecting the NMOSD BBB damage.

Mulberry leaf meal: A potential feed supplement for juvenile Megalobrama amblycephala "Huahai No. 1".

This study was performed to evaluate the potential application of mulberry leaf meal (ML) and fermented mulberry leaf meal (FML) as feed supplements in aquatic animals for developing varieties of practical and economical feed ingredients. Juveniles Megalobrama amblycephala were fed a basal diet (35.7% crude protein, 10.4% crude lipid; control group) supplemented with 2.22% and 4.44% mulberry leaf meals (ML2, ML4) and fermented mulberry leaf meals (FML2, FML4) for 8 weeks. Generally, the two-way ANOVA showed the supplementation level exhibited a prominent effect on the growth performance and physiological status of fish. Furthermore, the two-way ANOVA showed the supplementary fermented mulberry leaf meal increased plasma complement 4 (C4) content (P < 0.05). The weight gain rate (WGR, 145.87%) and the specific growth rate (SGR, 1.63%) were significantly increased in FML2 group compared with the control group (P < 0.05). The muscle crude lipid content and hepatosomatic index (HSI) were higher in FML2 group than that in ML2 group (P < 0.05). The hepatic GSH content in ML4 group and CAT, T-SOD activities in FML4 group were significantly increased compared with the control group (P < 0.05). The hepatic MDA content in FML4 group was significantly decreased compared with the FML2 group (P < 0.05). Total cholesterol (TC) contents showed a significant decrease in ML4 and FML4 groups compared with the control group (P < 0.05). Regarding the gene expression, sirtiun 1 (Sirt1) gene expression was elevated in FML2 group compared with the ML2 group (P < 0.05). Compare to the control group, FML2 diet significantly increased the expression of i-kappa-B alpha (IKBα) gene in liver, and decreased the expression of forkhead box O1 α (FoxO1α), toll-like receptors 4 (TLR4) and nuclear factor-kappa B (NF-κB) genes (P < 0.05). In conclusion, 2.22% FML promoted the growth performance of M. amblycephala and enhanced the anti-inflammatory responses by inhibiting TLR4/NF-κB signaling pathway. On the other hand, 4.44% FML reduced plasma lipid content (hypolipedemic effect) and improved the hepatic antioxidant capacity of M. amblycephala.

The clinical significance of low complement levels in patients with catastrophic antiphospholipid syndrome: A descriptive analysis of 73 patients from the "Catastrophic antiphospholipid syndrome registry".

OBJECTIVES: To explore the prevalence and clinical significance of low complement levels in patients with catastrophic antiphospholipid syndrome (CAPS). METHODS: We reviewed data from the "CAPS Registry" on C3 and/or C4 complement plasma protein levels during acute CAPS episodes. Patients were classified into those with low and normal complement levels. Data on clinical presentation, with special focus on thrombotic microangiopathy (TMA) features, diagnosis of systemic lupus erythematosus (SLE), and antiphospholipid antibody (aPL) profile were reviewed. The chi-square exact test was performed to evaluate differences between categorical data. RESULTS: The "CAPS Registry" includes 566 patients with a total of 578 episodes of CAPS. Data on complement plasma protein levels was available in 73 episodes from the same number of patients. Low levels of C3 and/or C4 complement plasma proteins were detected in 42 (58%) CAPS episodes. Low complement levels were more common in SLE patients (55% SLE vs. 19% No SLE; p<0.001). The frequencies of clinical TMA (72% vs. 80%; p=0.4) or TMA syndrome (86% vs. 84%, p=0.9), frequency of triple aPL triple positivity (67% vs 33%; p=0.3), or the mortality (35% vs. 31%; p=0.7) were similar between low and normal complement groups. CONCLUSION: In our study, low levels of C3 and C4 plasma proteins are detected in 58% episodes of CAPS, which were not associated with clinical presentation including TMA features, aPL triple positivity, or mortality.