Levels Of Complement Components Research Articles

Assessment of immune status markers during occupational lead exposure

The immune system is sensitive to the effects of environmental factors, and according to numerous studies, lead has an immunotoxic effect. At the same time, there is evidence of the multidirectional nature of the impact of lead on the immune system, determined by the degree of exposure to this heavy metal, which makes it current to study changes in immunological markers in workers of a modern lead recycling plant, taking into account levels and complexity of exposure. In the era of personalized medicine, monitoring the potential influence of occupational factors exposure on the immune system can facilitate a personalized approach to the prevention of work-related health conditions. The aim of the study: to evaluate changes in immune status markers among employees of lead recycling plant. The main group – 62 men working at a lead recycling plant, the control group – 47 men not exposed to occupational factors. Laboratory examination included a determination of the lead blood level, a clinical blood test, the serum levels of IL- 1â, IL- 10, IL- 8, MCP-1, C3 and C4 complement components, IgA, IgM, IgG. In the main group, compared to the control group, a higher number of neutrophils, lymphocytes, monocytes, higher levels of IL-8, C3 and C4 components of the complement system, and lower levels of IgM were detected. In the main group, the following changes in markers were significantly more often detected in comparison with reference values: an increase in the C3 component of complement (51.6% in the main group compared to 12.5% in the control group), decreased IgG (24.2% compared to 6.2%) and increased IgA (22.6% compared to 6.2%). Associations were identified between the lead blood level and the number of lymphocytes, the level of IgG, between work experience in contact with lead and the level of MCP-1 and C3 complement components. The results of the studies revealed the presence of changes in the immune status markers of workers at a lead recycling plant, which demonstrate a proinflammatory effect of lead and an influence on the humoral immune status. The identified changes in immunological parameters may underlie the mechanisms of formation of pathological conditions associated with lead exposure, which determines the relevance of continuing research to assess dynamic changes in immunological parameters and develop a system for monitoring the immune status of workers exposed to lead and its compounds to optimize preventive measures.

Dynamic features of the humoral immunity in patients with acute coronary syndrome depending on the content of B lymphocytes with the CD3<sup>-</sup>CD19<sup>+</sup>CD5<sup>+</sup> phenotype, who have and have not COVID-19

The purpose of the work was to study the dynamic features of the humoral immunity in patients with acute coronary syndrome depending on the content of B lymphocytes with the CD3-CD19+CD5+ phenotype, who had and did not have COVID-19. We analyzed data on humoral immunity in men aged 40 to 65 years with acute coronary syndrome, who had and did not have COVID-19, depending on the content of B lymphocytes with the CD3-CD19+CD5+ phenotype. All patients underwent coronary angiography with further stenting of the coronary arteries. The values of lymphocytes with the CD45+CD3-CD19+ phenotype and the presence or absence of COVID-19 previously were taken into account. Using the flow cytometry method, 2 groups were gated using the pan-leukocyte marker CD45+: the subgroup of B lymphocytes CD3-CD19+CD5+ and the subgroup of B lymphocytes CD3-CD19+CD5-, B lymphocytes (CD45+CD3-CD19+). Levels of total IgA, IgG, IgM, C1-inhibitor, C3a and C5a complement components by enzyme immunoassay. After coronary artery stenting, B lymphocytes (CD3-CD19+CD5+) significantly increased in the group of people with COVID-19, with initially low levels of these cells (p 0.01) and normal cells (p 0.05). In individuals who had COVID-19 and did not have this disease, with initially decreased CD3-CD19+CD5+ cells, B lymphocytes (CD45) increased significantly (p 0.001 and p 0.05, respectively) over time (p 0.05+CD3-CD19+), B lymphocytes (CD3-CD19+CD5-). In the group of patients who recovered from COVID-19 with normal CD3-CD19+CD5+ cells, the relative number of B-lymphocytes decreased over time (p 0.01) (CD45+CD3-CD19+) and CD3-CD19+CD5- cells. In persons who had previously suffered from COVID-19, with increased CD3-CD19+CD5+ cells, the number of B-lymphocytes (CD45+) significantly (p 0.05) decreased over time CD3-CD19+), in those who did not have COVID-19 with high above-mentioned cells, immunoglobulin A significantly (p 0.05) increased. The most severe clinically was the group of people with low CD3-CD19+CD5+B cells and COVID-19 in the anamnesis.

Visualization and characterization of complement activation in acetylcholine receptor antibody seropositive myasthenia gravis.

There are no blood biomarkers to monitor treatment effects in myasthenia gravis (MG) or studies visualizing the acetylcholine receptor (AChR) antibody-induced membrane attack complex (MAC) at the human muscle membrane. This study aimed to compare levels of complement activation products and native complement components in MG patients and healthy controls (HCs) and to model the AChR antibody-mediated attacks in human muscle cells. We assessed the complement components and activation product levels with enzyme-linked immunosorbent assay and magnetic bead-based sandwich assays in plasma and sera of 23 MG patients and matched HCs. Receiver operator characteristic (ROC) curve analysis evaluated the diagnostic accuracy. Complement levels were correlated with the myasthenia gravis composite (MGC) scores. AChR+ MG modeling in human muscle cells used sera from nine MG patients and three HCs. MG patients had significantly higher plasma levels of C3a (p < .0001), C5 (p = .0003), and soluble C5b-9 (sC5b-9; p < .0001) than HCs. The ROC curve analysis showed a clear separation between MG patients and HCs for plasma C3a (AUC = 0.9720; p < .0001) and sC5b-9 (AUC = 0.8917, p < .0001). MG patients had higher levels of plasma complement Factor I (FI; p = .0002) and lower properdin levels (p < .0001). The MGC had moderate correlations with plasma Factor B (FB), FI, and Factor H. AChR+ MG patient sera triggered the deposition of MAC and reduced AChRs. We suggest validating plasma C3a and sC5b-9 as blood biomarkers for complement activation in MG. Further, the in vitro study allowed visualization of MAC deposition after applying AChR+ MG sera on human muscle cells.

Growth and physiological response of Nile tilapia (Oreochromis niloticus) fed a fermented mixture of plant protein sources

This study aimed to assess the effects of diets containing a blend of plant protein sources (cottonseed meal, sunflower meal, and jojoba meal) fermented with yeast (Saccharomyces cerevisiae) at three different levels (25 %, 50 %, and 75 %) instead of fishmeal (FM) on the growth performance, anti-nutritional factors content, and blood profile response of Nile tilapia (Oreochromis niloticus). Four experimental diet (33.6 % crude protein) and (18.61 MJ kg−1 gross energy) were formulated. The study included four diets: a control diet, FCSJM-25 %, FCSJM-50 %, FCSJM-75 % which replaced fishmeal based on protein content. Fries (3.53± 0.07 g) were randomly allocated into twelve glass aquaria (180 L capacity) in triplicate per each treatment (25 fish/ aquarium) for 90 days. After the 90-day feeding trial, the results showed that fish fed the control diet, FCSJM-25 %, and FCSJM-50 % had the highest final body weight, weight gain, specific growth rate, and average daily gain, whereas fish fed FCSJM-75 % had the lowest values for these parameters. The best feed conversion ratio (FCR) was observed in fish fed FCSJM-25 % or FCSJM-50 % (P < 0.05). The highest apparent protein digestibility was found in fish fed the control diet or FCSJM-25 %. Diets with FCSJM-25 % had the highest white blood cells (WBCs) values (P < 0.05). Control diet, FCSJM-25 %, and FCSJM-50 % resulted in the highest levels of complement component (C3), C4, growth hormone, and IgM (P < 0.05). However, control diet had the highest triglyceride and HDL levels, while fish fed FCSJM-25 % had the highest levels of LDL (P < 0.05). Fish fed a diet with FCSJM-50 % recorded the highest cholesterol content. The control or FCSJM-25 % diets showed the highest values of creatinine, phosphorus, and calcium (P < 0.05). There were no significant differences in ALT, AST, and uric acid among the treatments. The study concluded that FM can be replaced with either FCSJM-25 % and FCSJM-50 % without affecting growth performance and feed utilization.

Clinical features and potential markers of disease in idiopathic non-histaminergic angioedema, a real-life study.

Idiopathic non-histaminergic acquired angioedema (InH-AAE) is a rare disease, with unknown etiology and pathogenesis, characterized by recurrent clinical manifestations and resistance to antihistamines and corticosteroids. We aim to evaluate clinical features and potential markers of disease in an Italian cohort of patients with InH-AAE. We enrolled 26 patients diagnosed with InH-AAE. Information about clinical features, treatments, routine laboratory investigations, immunological and genetic tests were collected. We assessed plasma levels of complement components, angiogenic and lymphangiogenic mediators, proinflammatory cytokines and chemokines, and activity of phospholipases A2. Finally, patients underwent nailfold videocapillaroscopy (NVC); both quantitative and qualitative capillaroscopic parameters were analyzed. Plasma levels of VEGFs were similar in healthy controls and in InH-AAE patients. ANGPT1 was decreased in InH-AAE patients compared to controls while ANGPT2 was similar to controls. Interestingly, the ANGPT2/ANGPT1 ratio (an index of vascular permeability) was increased in InH-AAE patients compared to controls. sPLA2 activity, elevated in patients with C1-INH-HAE, showed differences also when measured in InH-AAE patients. TNF-α concentration was higher in InH-AAE patients than in healthy controls, conversely, the levels of CXCL8, and IL-6 were similar in both groups. At the NVC, the capillary loops mainly appeared short and tortuous in InH-AAE patients. InH-AAE represents a diagnostic challenge.Due to the potential life-threatening character of this condition, a prompt identification of the potentially bradykinin-mediated forms is crucial. A better comprehension of the mechanism involved in InH-AAE would also lead to the development of new therapeutic approaches to improve life quality of patients affected by this disabling disease.

Association of complement components with risk of colorectal cancer: A systematic review and meta-analysis.

Complement components could contribute to the tumor microenvironment and the systemic immune response. Nevertheless, their role in colorectal cancer (CRC) remains a contentious subject. To elucidate the relationship between complement components and CRC risk and clinical characteristics. Searches were conducted in PubMed, the Cochrane Library, and the China National Knowledge Infrastructure database until June 1, 2023. We included cohort studies encompassing participants aged ≥ 18 years, investigating the association between complement components and CRC. The studies were of moderate quality or above, as determined by the Agency for Healthcare Research and Quality. The meta-analysis employed fixed-effects or random-effects models based on the I² test, utilizing risk ratio (RR) and their corresponding 95% confidence interval (CI) for outcomes. Sensitivity and subgroup analyses were performed to validate the robustness of the collective estimates and identify the source of heterogeneity. Data from 15 studies, comprising 1631 participants that met the inclusion criteria, were included in the meta-analysis. Our findings indicated that protein levels of cluster of differentiation 46 (CD46) (RR = 3.66, 95%CI: 1.75-7.64, P < 0.001), CD59 (RR = 2.86, 95%CI: 1.36-6.01, P = 0.005), and component 1 (C1) (RR = 5.88, 95%CI: 1.75-19.73, P = 0.004) and serum levels of C3 (standardized mean difference = 1.82, 95%CI: 0.06-3.58, P = 0.040) were significantly elevated in patients with CRC compared to healthy controls. Strong expression of CD55 or CD59 was associated with a higher incidence of lymph node metastasis, whereas strong CD46 expression correlated with a higher incidence of tumor differentiation compared to low CD46 expression (P < 0.05 for all). Although specific pooled results demonstrated notable heterogeneity, subgroup analyses pointed to regional differences as the primary source of inconsistency among the studies. Our analysis underscores that increased levels of specific complement components are associated with a heightened risk of CRC, emphasizing the potential significance of monitoring elevated complement component levels.

STING inhibition suppresses microglia-mediated synapses engulfment and alleviates motor functional deficits after stroke

Ischemic stroke is the leading cause of adult disability. Ischemia leads to progressive neuronal death and synapse loss. The engulfment of stressed synapses by microglia further contributes to the disruption of the surviving neuronal network and related brain function. Unfortunately, there is currently no effective target for suppressing the microglia-mediated synapse engulfment. Stimulator of interferon genes (STING) is an important participant in innate immune response. In the brain, microglia are the primary cell type that mediate immune response after brain insult. The intimate relationship between STING and microglia-mediated neuroinflammation has been gradually established. However, whether STING affects other functions of microglia remains elusive. In this study, we found that STING regulated microglial phagocytosis of synapses after photothrombotic stroke. The treatment of STING inhibitor H151 significantly improved the behavioral performance of injured mice in grid-walking test, cylinder test, and adhesive removal test after stroke. Moreover, the puncta number of engulfed SYP or PSD95 in microglia was reduced after consecutive H151 administration. Further analysis showed that the mRNA levels of several complement components and phagocytotic receptors were decreased after STING inhibition. Transcriptional factor STAT1 is known for regulating most of the decreased molecules. After STING inhibition, the nucleus translocation of phosphorylated STAT1 was also suppressed in microglia. Our data uncovered the novel regulatory effects of STING in microglial phagocytosis after stroke, and further emphasized STING as a potential drug-able target for post-stroke functional recovery.

Atractylodin, β-eudesmol, and (+)-hinesol in Atractylodes chinensis rhizomes improve glomerular injuries in high immunoglobulin A mice

Background: The rhizome of Atractylodes chinensis (Asteraceae), a crude drug of Japanese Kampo medicines, has been administered to patients with edema, nephrotic syndrome, and gastrointestinal disorders. Essential oils, such as sesquiterpenoids (e.g., β-eudesmol and hinesol) and atractylodin, are rich in the rhizomes. Previously, we discovered that atractylodin, a polyacetylene compound, found in an ethyl acetate (EtOAc)-soluble fraction from a methanol extract of A. chinensis rhizomes, possessed marked anti-inflammatory activities. Oral administration of the EtOAc-soluble fraction reduced immunoglobulin A (IgA) deposition in the renal glomeruli of high immunoglobulin A (HIGA) mice, a model of human IgA nephropathy. An increased serum IgA forms immune complexes and causes the deposition on renal glomeruli, leading to inflammation by the complement-mediated pathway. Objective: The aim of this study is to identify the compounds that reduce IgA deposition in an EtOAc-soluble fraction of A. chinensis rhizomes. Methods: Metabolites in the serum of HIGA and control BALB/c mice were analyzed by gas chromatography–mass spectrometry. A standard diet including each compound was fed to HIGA and BALB/c mice for 20 weeks to evaluate the improvement of glomerular IgA deposition. Results: Metabolomic analysis of serum suggested that the HIGA mice exhibit a state near the early stage of chronic kidney disease, compared with the BALB/c mice. When mice were orally administered each hydrophobic compound of A. chinensis rhizomes, it was revealed that atractylodin, as well as β-eudesmol and (+)-hinesol, efficiently inhibited glomerular IgA deposition. Furthermore, the renal levels of complement component 3 (C3) and proinflammatory cytokine mRNAs were decreased, when the hydrophobic compounds were orally administered to HIGA mice. Conclusion: Atractylodin, β-eudesmol, and (+)-hinesol may inhibit glomerular IgA deposition, probably by attenuating complement-mediated injuries and suppressing proliferation of mesangial cells in the renal glomeruli. These compounds might improve the pathological findings of human IgA nephropathy. Keywords: Atractylodes chinensis; Crude drug; Immunoglobulin A nephropathy; Metabolomics; Complement

Differentiated pattern of complement system activation between MOG-IgG-associated disease and AQP4-IgG-positive neuromyelitis optica spectrum disorder.

Myelin oligodendrocyte glycoprotein antibody (MOG) immunoglobulin G (IgG)-associated disease (MOGAD) has clinical and pathophysiological features that are similar to but distinct from those of aquaporin-4 antibody (AQP4-IgG)-positive neuromyelitis optica spectrum disorders (AQP4-NMOSD). MOG-IgG and AQP4-IgG, mostly of the IgG1 subtype, can both activate the complement system. Therefore, we investigated whether the levels of serum complement components, regulators, and activation products differ between MOGAD and AQP4-NMOSD, and if complement analytes can be utilized to differentiate between these diseases. The sera of patients with MOGAD (from during an attack and remission; N=19 and N=9, respectively) and AQP4-NMOSD (N=35 and N=17), and healthy controls (N=38) were analyzed for C1q-binding circulating immune complex (CIC-C1q), C1 inhibitor (C1-INH), factor H (FH), C3, iC3b, and soluble terminal complement complex (sC5b-9). In attack samples, the levels of C1-INH, FH, and iC3b were higher in the MOGAD group than in the NMOSD group (all, p<0.001), while the level of sC5b-9 was increased only in the NMOSD group. In MOGAD, there were no differences in the concentrations of complement analytes based on disease status. However, within AQP4-NMOSD, remission samples indicated a higher C1-INH level than attack samples (p=0.003). Notably, AQP4-NMOSD patients on medications during attack showed lower levels of iC3b (p<0.001) and higher levels of C3 (p=0.008), C1-INH (p=0.004), and sC5b-9 (p<0.001) compared to those not on medication. Among patients not on medication at the time of attack sampling, serum MOG-IgG cell-based assay (CBA) score had a positive correlation with iC3b and C1-INH levels (rho=0.764 and p=0.010, and rho=0.629 and p=0.049, respectively), and AQP4-IgG CBA score had a positive correlation with C1-INH level (rho=0.836, p=0.003). This study indicates a higher prominence of complement pathway activation and subsequent C3 degradation in MOGAD compared to AQP4-NMOSD. On the other hand, the production of terminal complement complexes (TCC) was found to be more substantial in AQP4-NMOSD than in MOGAD. These findings suggest a strong regulation of the complement system, implying its potential involvement in the pathogenesis of MOGAD through mechanisms that extend beyond TCC formation.

Main circulating CD8&lt;sup&gt;+&lt;/sup&gt; T cell subsets in patients with systemic lupus erythematosus

Relevance. Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by loss of immune tolerance and sustained production of autoantibodies.The aim of the study – to compare composition of peripheral blood cytotoxic CD8+ T lymphocytes (Tc) subsets and assess the clinical significance of them in systemic lupus erythematosus. Materials and methods. A total of 35 SLE patients and 49 healthy volunteers were included in the study. Phenotyping of peripheral blood T cell subpopulations was carried out by means of flow cytometry. T lymphocytes were determined using CD3+, CD4+, CD8+ antibodies. Tc were identified by using CD45RA and CD62L antibodies. Also the expression of chemokine receptors (CCR4, CCR6, CXCR3 and CXCR5) on Tc cells was assessed and the main Tc subpopulations were determined: Type 1 (Tc1), type 2 (Tc2), type 17 (Tc17), type 17/1 (Tc17.1), type 17/22 (Tc17.22) cytotoxic cells and T follicular cytotoxic cells (Tfc).Results. The absolute and relative number of Tc was significantly higher in the group of patients with SLE compared with the control group. Additionally, there was a significant decrease in the relative number of Tc1, Tc 17.1 and Tfc1 and a significant increase in the relative number of Tc2, Tfc 17 and Tfc17.1 within the SLE group when compared to the control group. There were significant positive correlationfor Tc1 and levels of C3 and C4 complement components (r=0.404, p&lt;0.05).Conclusions. The absolute and relative number of peripheral blood Tc subsets is altered in SLE patients compared with the control group. It was found that patients with SLE contained increased number of Tc2 cells, which seems to be associated with markers of disease activity. These results demonstrate a prominent pathological role of Tc2 in SLE. While Tc1, Tc17, Tc17.1, Tfc subsets probably have regulatory functions

Effects of dietary bacterial culture of fengycin-producing Bacillus subtilis on growth performance, intestinal and hepatopancreas health, intestinal microbiota and disease resistance of common carp (Cyprinus carpio)

Probiotics are important for the normal physiological functions of fish and are used as feed additives in many aquatic animals. The purpose of this study is to explore the effects of dietary bacterial culture of fengycin-producing Bacillus subtilis (B. subtilis) on growth performance, intestinal and hepatopancreas health, intestinal microbiota and disease resistance of common carp (Cyprinus carpio). Three diets were formulated with supplementation of bacterial culture of fengycin-producing B. subtilis at 0, 0.3 and 0.5 g/kg levels, and these diets were defined as control, BS0.3 and BS0.5, respectively. After 6-week feeding, the infiltration of inflammatory cells was improved in the BS0.3 and BS0.5 groups. And the anti-inflammatory cytokines (interleukin (IL)-10 and tumor growth factor β (TGF-β) were prominently increased in the hepatopancreas of fish fed with dietary B.subtilis diets (P < 0.05). The activity of lysozyme, the levels of complement component (C) 3 and C4 were remarkably increased in the hepatopancreas and intestine of fish fed with B.subtilis supplemented diets (P < 0.05). Histological (intestinal villi height was increased in BS0.3 and BS0.5 groups) (P < 0.05) and the expression of the gut physical barrier-related genes (Zona occludens-1 (ZO-1) and occludin) were increased in the B.subtilis supplemented groups (P < 0.05). The expression of pro-inflammatory cytokines (IL-1β, IL-6 and tumor necrosis factor α (TNF-α) and anti-inflammatory cytokines (IL-10 and TGF-β) were remarkably up-regulated in the intestine of fish fed with BS0.3 diet (P < 0.05), while the expression of IL-6 was remarkably diminished in the intestine of fish fed with BS0.5 diet (P < 0.05). Besides, the intestinal microbiota analysis illustrated that in the intestine of the fish groups fed with BS0.3 and BS0.5 diets, the abundance of Fusobacteriota and Cetobacterium were prominently increased (P < 0.05). After challenged with Aeromonas veronii Hm091, the survival rate of fish fed with BS0.3 diet was markedly improved (P < 0.05). Based on these results, supplementation of bacterial culture of fengycin-producing B. subtilis at a level of 0.3 g/kg has beneficial effects on immunity, intestinal microbiota, and disease resistance of common carp.

Association of time-averaged serum uric acid level with clinicopathological information and long-term outcomes in patients with IgA nephropathy.

Whether serum uric acid (SUA) at baseline could been identiûed as a risk factor for progression in IgA nephropathy (IgAN) patients remains unclear, therefore, long- term SUA control levels must be monitored. We aimed to investigate the relevant factors affecting time-averaged SUA (TA-SUA) and to assess the prognostic value of TA-SUA in IgAN. This retrospective study included 152 patients with IgAN. The relationships between TA-SUA and clinicopathological features and renal outcomes (defined as the doubling of the baseline serum creatinine level or end-stage renal disease) were analyzed in groups divided by quartiles of TA-SUA levels, the presence of hyperuricemia, and sex. Patients with high TA-SUA levels had higher levels of baseline SUA, blood urea nitrogen (BUN), triglycerides, serum C3 and serum C4 and were more likely to be male and have hypertension, proteinuria, poor renal function, and pathological injuries including high grades of tubular atrophy/interstitial fibrosis (T1-T2). These patients had a poorer prognosis compared with patients with low TA-SUA levels. The TA-SUA level was positively correlated with baseline age and BUN, triglycerides, serum C3, and serum C4 levels, and negatively correlated with baseline eGFR. Survival curve analysis indicated that persistent hyperuricemia was associated with significantly poorer renal outcomes than normo-uricemia in both men and women. The TA-SUA level also was an independent predictor of renal outcome in patients with IgAN, with optimal cutoû values of 451.38 µmol/L (area under the curve (AUC) = 0.934) for men and 492.83 µmol/L (AUC = 0.768) for women. The TA-SUA level is associated with triglyceride level, complement component levels, renal function, and pathological severity of IgAN, and it may be a prognostic indicator in male and female patients with IgAN.

Association of elevated levels of peripheral complement components with cortical thinning and impaired logical memory in drug-naïve patients with first-episode schizophrenia

Schizophrenia has been linked to polymorphism in genes encoding components of the complement system, and hyperactive complement activity has been linked to immune dysfunction in schizophrenia patients. Whether and how specific complement components influence brain structure and cognition in the disease is unclear. Here we compared 52 drug-naïve patients with first-episode schizophrenia and 52 healthy controls in terms of levels of peripheral complement factors, cortical thickness (CT), logical memory and psychotic symptoms. We also explored the relationship between complement factors with CT, cognition and psychotic symptoms. Patients showed significantly higher levels of C1q, C4, factor B, factor H, and properdin in plasma. Among patients, higher levels of C3 in plasma were associated with worse memory recall, while higher levels of C4, factor B and factor H were associated with thinner sensory cortex. These findings link dysregulation of specific complement components to abnormal brain structure and cognition in schizophrenia.

Voluntary wheel running prevents formation of membrane attack complexes and myelin degradation after peripheral nerve injury

Regular aerobic activity is associated with a reduced risk of chronic pain in humans and rodents. Our previous studies in rodents have shown that prior voluntary wheel running can normalize redox signaling at the site of peripheral nerve injury, attenuating subsequent neuropathic pain. However, the full extent of neuroprotection offered by voluntary wheel running after peripheral nerve injury is unknown. Here, we show that six weeks of voluntary wheel running prior to chronic constriction injury (CCI) reduced the terminal complement membrane attack complex (MAC) at the sciatic nerve injury site. This was associated with increased expression of the MAC inhibitor CD59. The levels of upstream complement components (C3) and their inhibitors (CD55, CR1 and CFH) were altered by CCI, but not increased by voluntary wheel running. Since MAC can degrade myelin, which in turn contributes to neuropathic pain, we evaluated myelin integrity at the sciatic nerve injury site. We found that the loss of myelinated fibers and decreased myelin protein which occurs in sedentary rats following CCI was not observed in rats with prior running. Substitution of prior voluntary wheel running with exogenous CD59 also attenuated mechanical allodynia and reduced MAC deposition at the nerve injury site, pointing to CD59 as a critical effector of the neuroprotective and antinociceptive actions of prior voluntary wheel running. This study links attenuation of neuropathic pain by prior voluntary wheel running with inhibition of MAC and preservation of myelin integrity at the sciatic nerve injury site.

Complement alternative pathway determines disease susceptibility and severity in antineutrophil cytoplasmic antibody (ANCA)–associated vasculitis

Activation of the alternative pathway (AP) of complement is involved in the pathogenesis of antineutrophil cytoplasmic antibody (ANCA)–associated vasculitis (AAV), although the underlying molecular mechanisms are unclear. To gain insight into the role of the AP, common gene variants in CFH/CFHR1-5, CFB, C3 and MCP, and longitudinal determinations of plasma C3, C4, FH, FHR-1, FHR-2, FHR-5, FB, properdin and sC5b-9 levels were analyzed in a Spanish AAV cohort consisting of 102 patients; 54 with active AAV (active cohort) and 48 in remission not receiving immunosuppressants or dialysis therapy (remission cohort). The validation cohort consisted of 100 patients with ANCA-associated glomerulonephritis. Here, we demonstrated that common genetic variants in complement components of the AP are associated with disease susceptibility (CFB32Q/W) or severity of kidney damage in AAV (CFH-H1, CFHH2 and ΔCFHR3/1). Plasma levels of complement components were significantly different between active and remission cohorts. In longitudinal observations, a high degree of AP activation at diagnosis was associated with worse disease outcome, while high basal FHR-1 levels and lower FH/FHR-1 ratios determined severe forms of kidney associated AAV. These genetic and plasmatic findings were confirmed in the validation cohort. Additionally, autoantibodies against FH and C3 convertase were identified in one and five active patients, respectively. Thus, our study identified key genetic and plasma components of the AP that determine disease susceptibility, prognosis, and severity in AAV. Our data also suggests that balance between FH and FHR-1 is critical and supports FHR-1 as a novel AP-specific therapeutic target in AAV.

Multi-omics investigation of the resistance mechanisms of pomalidomide in multiple myeloma.

Despite significant therapeutic advances over the last decade, multiple myeloma remains an incurable disease. Pomalidomide is the third Immunomodulatory drug that is commonly used to treat patients with relapsed/refractory multiple myeloma. However, approximately half of the patients exhibit resistance to pomalidomide treatment. While previous studies have identified Cereblon as a primary target of Immunomodulatory drugs' anti-myeloma activity, it is crucial to explore additional mechanisms that are currently less understood. To comprehensively investigate the mechanisms of drug resistance, we conducted integrated proteomic and metabonomic analyses of 12 plasma samples from multiple myeloma patients who had varying responses to pomalidomide. Differentially expressed proteins and metabolites were screened, and were further analyzed using pathway analysis and functional correlation analysis. Also, we estimated the cellular proportions based on ssGSEA algorithm. To investigate the potential role of glycine in modulating the response of MM cells to pomalidomide, cell viability and apoptosis were analyzed. Our findings revealed a consistent decrease in the levels of complement components in the pomalidomide-resistant group. Additionally, there were significant differences in the proportion of T follicular helper cell and B cells in the resistant group. Furthermore, glycine levels were significantly decreased in pomalidomide-resistant patients, and exogenous glycine administration increased the sensitivity of MM cell lines to pomalidomide. These results demonstrate distinct molecular changes in the plasma of resistant patients that could be used as potential biomarkers for identifying resistance mechanisms for pomalidomide in multiple myeloma and developing immune-related therapeutic strategies.

Characteristics of Complement Protein Deposition in Proliferative Glomerulonephritis with Monoclonal Immunoglobulin Deposition.

Hypocomplementemia and complement co-deposition with monoclonal immunoglobulins in glomeruli are not rare in proliferative glomerulonephritis with monoclonal immunoglobulin deposits (PGNMID). Deposition of monoclonal immunoglobulins in glomeruli has been suggested to activate complement and cause kidney injury. However, the profiles of complement activation in PGNMID and their clinical and pathologic significance need to be clarified. Forty-six patients with PGNMID were enrolled. Proteomic analysis of glomeruli using laser microdissection and mass spectrometry was performed for ten patients with PGNMID to determine the composition of glomerular deposits. Kidney deposition of complement components was detected by immunohistochemistry and immunofluorescence. Urinary and plasma levels of complement components were measured by an enzyme-linked immunosorbent assay. Group differences were assessed using t tests or Mann-Whitney U tests depending on the distribution. Correlation analysis was performed using Spearman rank correlation or Pearson correlation. Laser microdissection and mass spectrometry-based proteomic analysis showed that complement components were the most enriched proteins deposited in the glomeruli of patients with PGNMID. Glomerular deposition of C3c, C4d, and C5b-9 was detected in most patients. Levels of urinary and plasma C3a, C5a, soluble C5b-9, C4d, Bb, and C1q as well as urinary mannose-binding lectin were significantly higher in patients with PGNMID compared with healthy controls. The intensity of C3c and C4d deposition in glomeruli correlated with serum creatinine and the percentage of crescents, respectively. Furthermore, levels of urinary complement components correlated positively with serum creatinine, urinary protein excretion, percentage of crescents, and global glomerulosclerosis in kidney biopsies, whereas plasma levels of most complement components did not show a significant correlation with clinicopathologic parameters. In multivariable analysis, a higher level of urinary C4d was identified as an independent risk factor of kidney failure. The complement system was found to be overactivated in PGNMID, and levels of urinary complements correlated with disease severity. A higher level of urinary C4d was identified as an independent risk factor of kidney failure.

CD44 Expression in Renal Tissue Is Associated with an Increase in Urinary Levels of Complement Components in Chronic Glomerulopathies.

It is suggested that activated CD44+ cells play a profibrogenic role in the pathogenesis of active glomerulopathies. Complement activation is also involved in renal fibrogenesis. The aim of the study was to evaluate the role of the activation of CD44+ cells in the kidney tissue and complement components' filtration to the urine as factors of renal tissue fibrosis in patients with glomerulopathies. In total, 60 patients with active glomerulopathies were included in our study: 29 patients with focal segmental glomerulosclerosis (FSGS), 10 patients with minimal change disease (MCD), 10 patients with membranous nephropathy (MN), and 11 patients with IgA nephropathy. The immunohistochemical peroxidase method was used to study the expression of CD44+ in kidney biopsies. Components of complement were analyzed in urine by the multiple reaction monitoring (MRM) approach using liquid chromatography. Strong CD44 expression was noted predominantly in PEC and mesangial cells (MC) in patients with FSGS, and to a lesser extent, in patients with MN and IgA nephropathy, and it was absent in patients with MCD. Expression of profibrogenic CD44+ in glomeruli correlated with the levels of proteinuria and complement C2, C3, and C9 components, and CFB and CFI in urine. The CD44+ expression scores in the renal interstitium correlated with the level of C3 and C9 components of complement in the urine and the area of tubulo-interstitial fibrosis. The strongest expression of CD44+ was found in the glomeruli (MC, PEC, and podocytes) of patients with FSGS compared with other glomerulopathies. The CD44 expression score in the glomeruli and interstitium is associated with high levels of complement components in the urine and renal fibrosis.

Occult hepatitis B in blood donation centers.

Occult hepatitis B (OHB) is characterized by the presence of hepatitis B virus (HBV) DNA in the blood of individuals who test negative for the hepatitis B surface antigen (HBsAg). OHB in blood donors can lead to HBV transmission through transfusions, yet the prevalence of OHB in Basrah, Iraq, is unknown. This study aimed to determine the prevalence of OHB in blood donation centers in Basrah and investigate the immune response to HBV in OHB-positive donors. We recruited 450 blood donors and categorized them into four groups based on HBV markers: the HBsAg-negative/HBsAb-negative/HBcAb-positive group, the recovery group (HBsAg-negative/HBsAb-positive/HBcAb-positive), the patient group (HBsAg-positive/HBsAb-negative/HBcAb-positive), and the apparently healthy group (negative for all HBV markers). We measured levels of IgG, IgM, complement components (C3 and C4), ALT, AST, and serum ALP in OHB-positive donors. Of the 450 donors, 97 (21.6%) were OHB-positive. IgG levels were significantly higher than IgM levels in OHB-positive donors. Healthy and HBsAg-negative/HBsAb-positive donors had significantly lower C3 levels than patients. IgG levels were significantly higher than IgM in both the patient and recovery groups. C3 levels were higher than C4 levels in all groups. The serum ALP level was significantly higher in the patient group. OHB prevalence in Basrah blood donors is high, indicating the potential for HBV transmission. OHB-positive donors showed an immune response to HBV. Our study provides insights into OHB prevalence and immune response in Basrah, with implications for diagnostic and therapeutic approaches in blood donation centers.

Managing Diagnosis, Treatment, and Burden of Disease in Hereditary Angioedema Patients with Normal C1-Esterase Inhibitor.

Hereditary angioedema (HAE) is a rare, chronic, and debilitating genetic disorder characterized by recurrent and unpredictable swelling episodes that primarily affect the subcutaneous and/or submucosal tissues of the extremities, larynx, face, abdomen, and genitals. Most cases of HAE are caused by mutations in the serpin family G member 1 gene (SERPING1), which encodes C1-esterase inhibitor (C1-INH) protein. Mutations in SERPING1 lead to deficient (type I HAE-C1-INH) or dysfunctional (type II HAE-C1-INH) C1-INH protein and subsequent dysregulation of the kallikrein-bradykinin cascade. However, some patients present with a third type of HAE (HAE-nI-C1-INH), which was first described in the year 2000 and is characterized by an absence of mutations in SERPING1. Although mutations in the coagulation factor XII, angiopoietin-1, plasminogen, kininogen-1, myoferlin, and heparan sulfate-glucosamine 3-O-sulfotransferase-6 genes have been identified in some patients with HAE-nI-C1-INH, genetic cause is still unknown in many cases, hindering full elucidation of the pathology of this HAE subtype. Diagnosis of HAE-nI-C1-INH is also further complicated by the fact that patients typically demonstrate normal plasma levels of C1-INH and complement component 4 protein and normal C1-INH functionality during laboratory analysis. Therefore, we review the challenges associated with diagnosing, treating, and living with HAE-nI-C1-INH. We conclude that raising awareness of the presenting features of HAE-nI-C1-INH within the clinical setting and among the general public is critical to aid earlier suspicion and diagnosis of the disease. Furthermore, adopting an individualized approach to HAE-nI-C1-INH treatment is essential to help address the current and significant unmet needs in this patient population.