OBJECTIVE: To investigate the effects of fecal microbiota transplantation (FMT) on intestinal microbiome and organism in patients with severe pneumonia during the convalescence period. METHODS: A prospective non-randomized controlled study was conducted. From December 2021 to May 2022, patients with severe pneumonia during the convalescence period who received FMT (FMT group) and patients with severe pneumonia during the convalescence period who did not receive FMT (non-FMT group) admitted to the First Affiliated Hospital of Guangzhou Medical University were enrolled. The differences of clinical indicators, gastrointestinal function and fecal traits between the two groups were compared 1 day before and 10 days after enrollment. The 16S rDNA gene sequencing technology was used to analyze the changes of intestinal flora diversity and different species in patients with FMT before and after enrollment, and metabolic pathways were analyzed and predicted by Kyoto Encyclopedia of Genes and Genomes database (KEGG). Pearson correlation method was used to analyze the correlation between intestinal flora and clinical indicators in FMT group. RESULTS: The level of triacylglycerol (TG) in FMT group was significantly decreased at 10 days after enrollment compared with before enrollment [mmol/L: 0.94 (0.71, 1.40) vs. 1.47 (0.78, 1.86), P < 0.05]. The level of high-density lipoprotein cholesterol (HDL-C) in non-FMT group was significantly decreased at 10 days after enrollment compared with before enrollment (mmol/L: 0.68±0.27 vs. 0.80±0.31, P < 0.05). There were no significant differences in other clinical indexes, gastrointestinal function or fecal character scores between the two groups. Diversity analysis showed that the α diversity indexes of intestinal flora in FMT group at 10 days after enrollment were significantly higher than those in non-FMT group, and β diversity was also significantly different from that in non-FMT group. Differential species analysis showed that the relative abundance of Proteobacteria at the level of intestinal flora in FMT group at 10 days after enrollment was significantly lower than that in non-FMT group [8.554% (5.977%, 12.159%) vs. 19.285% (8.054%, 33.207%), P < 0.05], while the relative abundance of Fusobacteria was significantly higher than that in non-FMT group [6.801% (1.373%, 20.586%) vs. 0.003% (0%, 9.324%), P < 0.05], and the relative abundance of Butyricimonas, Fusobacterium and Bifidobacterium at the genus level of the intestinal flora was significantly higher than that in non-FMT group [Butyricimonas: 1.634% (0.813%, 2.387%) vs. 0% (0%, 0.061%), Fusobacterium: 6.801% (1.373%, 20.586%) vs. 0.002% (0%, 9.324%), Bifidobacterium: 0.037% (0%, 0.153%) vs. 0% (0%, 0%), all P < 0.05]. KEGG metabolic pathway analysis showed that the intestinal flora of FMT group was changed in bisphenol degradation, mineral absorption, phosphonate and phosphinate metabolism, cardiac muscle contraction, Parkinson disease and other metabolic pathways and diseases. Correlation analysis showed that Actinobacteria and prealbumin (PA) in intestinal flora of FMT group were significantly positively correlated (r = 0.53, P = 0.043), Bacteroidetes was positively correlated with blood urea nitrogen (BUN; r = 0.56, P = 0.029) and complement C3 (r = 0.57, P = 0.027), Firmicutes was positively correlated with BUN (r = 0.56, P = 0.029) and complement C3 (r = 0.57, P = 0.027), Fusobacteria was significantly positively correlated with immunoglobulin M (IgM; r = 0.71, P = 0.003), Proteobacteria was significantly positively correlated with procalcitonin (PCT; r = 0.63, P = 0.012) and complement C4 (r = 0.56, P = 0.030). CONCLUSIONS FMT can reduce TG level, reconstruct intestinal microecological structure, change body metabolism and function, and alleviate inflammatory response by reducing the relative abundance of harmful bacteria in patients with severe pneumonia during the convalescence period.
Humans ; Fecal Microbiota Transplantation ; Complement C3 ; Convalescence ; Prospective Studies ; Feces

OBJECTIVE: To investigate the risk factors of different types of Henoch-Schönlein purpura (HSP) in Tibetan patients at high altitude, as to provide reference for correctly identifying high-risk patients. METHODS: A retrospective study was used to analyze the 304 HSP patients admitted to Tibet Autonomous Region People's Hospital from April 2014 to March 2022. The gender, age, allergic history, family history, clinical type, laboratory indexes (hemoglobin, platelet count, eosinophil, C-reactive protein (CRP), albumin, immunoglobulin G, immunoglobulin A, complement C3 and C4) were analyzed retrospectively. Univariate and multivariate Logistic regression analysis to screen for risk factors affecting different types of HSP. RESULTS: Renal HSP patients showed higher IgA [(9.2±1.7) g/L vs. (6.4±2.4) g/L, P=0.015], lower complement C3 [(203.3±21.6) mg/dL vs. (301.1±19.5) mg/dL, P=0.043], and complement C4 [(33.5±2.3) mg/dL vs. (53.0±7.2) mg/dL, P=0.032]. The patients with abdominal HSP showed lower levels of hemoglobin [(119.6±19.6) g/L vs. (146.6±47.3) g/L, P=0.038] and plasma albumin [24.8 (22.1, 33.9) g/L vs. 32.6 (24.6, 35.1) g/L, P=0.045]. The patients with articular HSP exhibited higher CRP [13.5 (0.2, 20.6) g/L vs. 7.5 (0.1, 15.2) g/L, P=0.036] and erythrocyte sedimentation rate (ESR) [24 (5, 40) mm/h vs. 15 (4, 30) mm/h, P=0.049]. Elevated IgA and decreased complement C4 were risk factors for renal HSP, anemia and decreased plasma albumin were risk factors for abdominal HSP, and elevated CRP was a risk factor for articular HSP. CONCLUSION The clinical characteristics of different types of HSP in plateau areas were different. Patients with high IgA, low complement C4, anemia, hypoalbuminemia, and significantly elevated CRP should be highly vigilant. Early and effective intervention can improve the clinical efficacy, avoid severe development, and improve the prognosis.
Humans ; Retrospective Studies ; Tibet/epidemiology* ; Complement C3/analysis* ; IgA Vasculitis/complications* ; Altitude ; Complement C4 ; C-Reactive Protein/analysis* ; Immunoglobulin A ; Risk Factors ; Anemia ; Hemoglobins/analysis* ; Serum Albumin/analysis*

Objective: To report the clinical features and genetic variations of monogenic lupus caused by DNASE1L3 deficiency and to introduce preliminary experience on diagnosis and treatment for this disease. Methods: Clinical data of 3 children from the same pedigree were collected who were diagnosed with DNASE1L3 defect-associated monogenic lupus in August 2020 by Department of Pediatrics, Peking Union Medical College Hospital referred from Department of Pediatrics, Boai Hospital of Zhongshan. DNA was extracted from the peripheral blood of the patients and their parients to perform genetic analysis and confirmation. Six interferon-stimulated genes were relatively quantified to examine the activation of the type I interferon signaling. "DNASE1L3" "systemic lupus erythematosus" and "SLE" were searched in PubMed, Wangfang Data, CNKI databases for related reports from database established date to June 2022. Spectrum of genetic variations and clinical phenotypes were analyzed in combination with this pedigree. Results: Case 1, a 14-year-old girl with edema, hematuria, and heavy proteinuria, presented with membranous nephropathy. Case 2, the 12-year-old younger brother of case 1 with hematologic, cardiac, pulmonary, renal involvement, positive antinuclear antibody, positive anti-double-stranded DNA antibody and low complement C3, manifested with systemic lupus erythematosus. Case 3, the 8-year-old younger sister of case 1 with hematologic, cardiac, pulmonary and renal involvement, positive antinuclear antibody, positive anti-double-stranded DNA antibody, and low complement C3 and C4, manifested with systemic lupus erythematosus. Genetic testing revealed that all 3 patients carried homozygous deletions in exons 3 and 4 on DNASE1L3 gene. Interferon scores were elevated in case 1, 2 and their parents but normal in case 3. All 3 patients were diagnosed with monogenic lupus caused by DNASE1L3 defects. Literature searching identified 10 relevant publications in English and 0 publication in Chinese, involving 42 patients from 18 pedigrees (including the 3 cases from this pedigree). Nine variants were found: c.289_290delAC (p.T97Ifs*2), c.643delT (p.W215Gfs*2), c.320+4delAGTA, c.321-1G>A, Ex5 del, c.433G>A, c.581G>A (p.C194Y), c.537G>A (p.W179X), and Ex3-4 del. The hotspot variants were c.643delT (43% (36/84)) and c.289_290delAC (36% (30/84)). Kidney was affected in 31 cases (74%) of the 42 cases. Among the 25 patients, joints were affected in 16 cases (64%), fever were reported in 13 cases (52%) hematologic system was involved 13 cases (52%), rash was present in 10 cases (40%), intestinal tract was involved in 8 cases (32%), lungs were involved in 6 cases (24%), eyes were involved in 4 cases (16%), and the heart was involved in 4 cases (16%). The 2 cardiopulmonary affected patients from literature showed poor prognosis, with 1 died, and 1 right heart failure. Conclusions: The clinical manifestations of monogenic lupus caused by DNASE1L3 defect are highly heterogenous, primarily with renal, blood, joint, intestinal, and cardiopulmonary involvement. There is no correlation between the genotype and the phenotype. DNASE1L3 defects were predominantly mediated by null varations including nonsense, splicing, frameshift and exon deletions. The hotspot variants are c.643delT and c.289_290delAC. DNASE1L3 defects should be cautioned in early-onset lupus-like patients with renal, joint and hematologic involvement. Cardiopulmonary involved patients require close monitoring for poor prognosis. Copy number variations should be carefully analyzed after negative whole exome sequencing.
Male ; Child ; Humans ; Homozygote ; Complement C3 ; Antibodies, Antinuclear ; DNA Copy Number Variations ; Sequence Deletion ; Interferons ; Lupus Erythematosus, Systemic/genetics* ; Antiviral Agents ; Endodeoxyribonucleases

OBJECTIVE: To investigate the clinical features and laboratory characteristics of primary autoimmune hemolytic anemia (AIHA) patients with negative results of direct antiglobulin test (DAT) by tube test but positive results by microcolumn gel assay, in order to provide references for the diagnosis of these patients. METHODS: 59 patients diagnosed with primary AIHA in our hospital from January 2015 to December 2020 were retrospectively analyzed. According to the results of tube test and microcolumn gel assay, the cases were divided into 3 groups, and the clinical and laboratory characteristics of each group were compared. RESULTS: The cases were grouped as follows: Group I, cases with negative results by both methods of DAT (n=5); Group II, cases with negative results by tube test but positive results by microcolumn gel assay (n=26); Group III, cases with positive results by both methods of DAT (n=28). There was no significant difference in age and sex between Group II and other groups, whereas the positive rate of anti-IgG + anti-C3d of Group II was lower than that in Group III (P=0.015). The main clinical manifestations of Group II were chest tightness, shortness of breath, fatigue, as well as yellow skin and sclera or dark urine, but the incidence rate of these symptoms was not significantly different from other groups. Anemia related indexes in Group II such as red blood cell (RBC) count and hemoglobin (Hb) were lower than the reference intervals, but there was no significant difference compared with other groups. Hemolysis related indexes in Group II such as reticulocyte (Ret) ratio, indirect bilirubin (IBIL), lactate dehydrogenase (LDH) and free-hemoglobin (F-Hb) were higher than the reference intervals, and the latter two items were signficantly higher than those in Group I (P=0.031 and P=0.036). Serum complement C3 and C4 in Group II were higher than those in Group III (P=0.010 and P=0.037). CONCLUSION Anemia severity of primary AIHA patients who were negative of DAT by tube test but positive by microcolumn gel assay was similar to those with negative or positive results by both DAT methods, but the mechanism and degree of complement system involved in hemolysis might be different. Results above may be helpful for laboratory diagnosis of this kind of patients.
Anemia, Hemolytic, Autoimmune/diagnosis* ; Bilirubin ; Complement C3 ; Coombs Test/methods* ; Erythrocytes ; Hemolysis ; Humans ; Lactate Dehydrogenases ; Negative Results ; Retrospective Studies

OBJECTIVE: To investigate the effect of complement C3 on the prognosis of patients with multiple myeloma (MM), and to establish a predictive model to evaluate the overall survival. METHODS: Eighty newly diagnosed MM patients were enrolled, and clinical characteristics, such as sex, age, platelet count, white blood cell count, ISS stage, FISH, levels of kappa and lammda chain, complement C3 and C4 were retrospectively analyzed. Cox regression model was used for univariate and multivariate analysis about risk factors that affecting the prognosis of the MM patients. A nomogram based on C3 level was established for predicting the prognosis of MM patients. RESULTS: The average age of the MM patients was 63.15±10.41, including 36 males and 44 females. The median overall survival (OS) was 36.3 months, and the median progression-free survival (PFS) was 35.2 months, the 3-year OS rate and PFS rate of the MM patients were 67.5% and 52.5%, respectively. The variants selected by univariate analysis were put into multivariate regression model, the result showed that C3 level ≥0.7 U/L and PLT count <100×10 CONCLUSION Patients with C3 level≥0.7 U/L or PLT count <100×10
Complement C3 ; Female ; Humans ; Male ; Multiple Myeloma ; Platelet Count ; Prognosis ; Retrospective Studies

Epilepsy is a brain condition characterized by the recurrence of unprovoked seizures. Recent studies have shown that complement component 3 (C3) aggravate the neuronal injury in epilepsy. And our previous studies revealed that TRPV1 (transient receptor potential vanilloid type 1) is involved in epilepsy. Whether complement C3 regulation of neuronal injury is related to the activation of TRPV1 during epilepsy is not fully understood. We found that in a mouse model of status epilepticus (SE), complement C3 derived from astrocytes was increased and aggravated neuronal injury, and that TRPV1-knockout rescued neurons from the injury induced by complement C3. Circular RNAs are abundant in the brain, and the reduction of circRad52 caused by complement C3 promoted the expression of TRPV1 and exacerbated neuronal injury. Mechanistically, disorders of neuron-glia interaction mediated by the C3-TRPV1 signaling pathway may be important for the induction of neuronal injury. This study provides support for the hypothesis that the C3-TRPV1 pathway is involved in the prevention and treatment of neuronal injury and cognitive disorders.
Animals ; Astrocytes/metabolism* ; Complement C3/metabolism* ; Epilepsy ; Mice ; Neurons/pathology* ; Status Epilepticus ; TRPV Cation Channels/metabolism*

The complement cascade is a central component of innate immunity which plays a critical role in brain inflammation. Complement C3a receptor (C3aR) is a key mediator of post-ischemic cerebral injury, and pharmacological antagonism of the C3a receptor is neuroprotective in stroke. Cerebral ischemia injures brain endothelial cells, causing blood brain barrier (BBB) disruption which further exacerbates ischemic neuronal injury. In this study, we used an in vitro model of ischemia (oxygen glucose deprivation; OGD) to investigate the protective effect of a C3aR antagonist (C3aRA, SB290157) on brain endothelial cells (bEnd.3). Following 24 hours of reperfusion, OGD-induced cell death was assessed by TUNEL and Caspase-3 staining. Western blot and immunocytochemistry were utilized to demonstrate that OGD upregulates inflammatory, oxidative stress and antioxidant markers (ICAM-1, Cox-2, Nox-2 and MnSOD) in endothelial cells and that C3aRA treatment significantly attenuate these markers. We also found that C3aRA administration restored the expression level of the tight junction protein occludin in endothelial cells following OGD. Interestingly, OGD/reperfusion injury increased the phosphorylation of ERK1/2 and C3aR inhibition significantly reduced the activation of ERK suggesting that endothelial C3aR may act via ERK signaling. Furthermore, exogenous C3a administration stimulates these same inflammatory mechanisms both with and without OGD, and C3aRA suppresses these C3a-mediated responses, supporting an antagonist role for C3aRA. Based on these results, we conclude that C3aRA administration attenuates inflammation, oxidative stress, ERK activation, and protects brain endothelial cells following experimental brain ischemia.
Blood-Brain Barrier ; Blotting, Western ; Brain Ischemia ; Brain ; Caspase 3 ; Cell Death ; Complement C3a ; Complement System Proteins ; Encephalitis ; Endothelial Cells ; Glucose ; Immunity, Innate ; Immunohistochemistry ; In Situ Nick-End Labeling ; In Vitro Techniques ; Inflammation ; Ischemia ; Neurons ; Occludin ; Oxidative Stress ; Phosphorylation ; Reperfusion ; Stroke ; Tight Junctions

OBJECTIVE: To study the clinical value of lymphocyte subsets, immunoglobulins, and complement C3 and C4 in the evaluation of immune status in children with hand-foot-mouth disease (HFMD). METHODS: A total of 282 children with HFMD were enrolled as the HFMD group, and 130 healthy children were enrolled as the healthy control group. The percentages of peripheral CD3, CD4, and CD8 T lymphocytes, CD19 B lymphocytes, and CD56 natural killer cells were measured. The CD4/CD8 ratio was calculated. The levels of immunoglobulin A (IgA), immunoglobulin M (IgM), immunoglobulin G (IgG), and complement C3 and C4 were measured. RESULTS: The multivariate analysis showed that compared with the healthy control group, the HFMD group had significantly lower percentages of CD3, CD4, and CD8 T lymphocytes and levels of complement C3 and C4 (P<0.05), as well as significantly higher percentage of CD56 natural killer cells and level of IgG (P<0.05). The individual effect analysis showed that the children aged 0-3 years in the HFMD group had a significantly higher CD4/CD8 ratio than the healthy control group (P<0.05); boys aged 0-3 and ≥3 years in the HFMD group had a significantly higher level of IgM than the healthy control group (P<0.05); boys aged ≥3 years and girls aged 0-3 years in the HFMD group had a significantly lower level of IgA than the healthy control group (P<0.05). CONCLUSIONS Cellular and humoral immunity disorders are observed in children with HFMD. The monitoring of lymphocyte subsets and immunoglobulin levels can provide a laboratory basis for immune status assessment in children with HFMD.
Child, Preschool ; Complement C3 ; Complement C4 ; Female ; Hand, Foot and Mouth Disease ; Humans ; Immunoglobulins ; Infant ; Infant, Newborn ; Killer Cells, Natural ; Lymphocyte Count ; Lymphocyte Subsets ; Male

Atypical hemolytic uremic syndrome (aHUS), a rare form of thrombotic microangiopathy, is distinguished from the typical form by the absence of a preceding verotoxin-producing Escherichia coli infection. Notably, aHUS occurs in association with genetic or acquired disorders causing dysregulation of the alternative complement pathway. Patients with aHUS may show the presence of anti-complement factor H (CFH) autoantibodies. This acquired form of aHUS (anti-CFH-aHUS) primarily affects children aged 9–13 years. We report a case of a 13-year-old Lao girl with clinical features of aHUS (most likely anti-CFH-aHUS). The initial presentation of the patient met the classical clinical triad of thrombotic microangiopathy (microangiopathic hemolytic anemia, thrombocytopenia, and acute kidney injury) without preceding diarrheal illness. Low serum levels of complement 3 and normal levels of complement 4 indicated abnormal activation of the alternative complement pathway. Plasma infusion and high-dose corticosteroid therapy resulted in improvement of the renal function and hematological profile, although the patient subsequently died of infectious complications. This is the first case report that describes aHUS (possibly anti-CFH-aHUS) in Laos.
Adolescent ; Anemia, Hemolytic ; Atypical Hemolytic Uremic Syndrome ; Autoantibodies ; Child ; Complement C3 ; Complement C4 ; Complement Factor H ; Complement Pathway, Alternative ; Female ; Humans ; Immunosuppression ; Kidney ; Laos ; Plasma ; Shiga-Toxigenic Escherichia coli ; Thrombocytopenia ; Thrombotic Microangiopathies

To assess the value of immunohistochemical analysis for expressions of C3d, C4d, IgG, IgG4, and CD123 in the diagnosis of autoimmune skin diseases.
 Methods: We investigated the expressions of C3d, C4d, IgG, IgG4, and CD123 in paraffin-embedded, formalin-fixed tissues from 27 lupus erythematosus cases, including 8 discoid lupus erythematosus (DLE) cases, 4 subacute cutaneous lupus erythematosus (SCLE) cases, and 15 systemic lupus erythematosus (SLE) cases. Tissues from 15 dermatomyositis (DM) cases, 15 bullous pemphigoid (BP) cases, and 15 pemphigus cases were examined by immunohistochemical analysis. The differences in expression rates of C3d, C4d, IgG, IgG4, and CD123 between immunohistochemical staining and direct immunofluorescence were compared in the diagnosis of these diseases.
 Results: In the lupus erythematosus group, the positive rates of C3d and C4d deposited along the dermoepidermal junction were 85.2% and 51.9%, respectively. In the dermatomyositis group, the positive rates of C3d and C4d deposited along the dermoepidermal junction were 40% and 0, respectively. The expressions of C3d and C4d in lupus erythematosus tissues were significantly higher than those in DM tissues (P<0.05). The expression of CD123 protein in skin lesions of the lupus group was significantly higher than that in the DM group (P<0.05). In the BP group, the positive rates of C3d and C4d deposited along the dermoepidermal junction were 100% and 86.7%, respectively. In the pemphigus group, the positive rates of C3d and C4d deposited in the intercellular space of keratinocytes were 100% and 60%, respectively. The expressions of IgG and IgG4 in pemphigus tissues were higher than those in BP tissues (P<0.05). And the ratios of IgG4 to IgG in the pemphigus group was significantly higher than that in the BP group (P<0.05).
 Conclusion: The assays of C3d and C4d define an important diagnostic adjunct in evaluation of lupus erythematosus, BP and pemphigus. In some cases, it may even replace the direct immunofluorescence as a diagnostic adjunct. The expression of CD123 possesses certain clinical significance for the differential diagnosis of lupus erythematosus, and IgG4 and IgG expressions have adjunctive diagnostic significance for pemphigus.
Autoimmune Diseases ; Complement C3d ; Complement System Proteins ; Humans ; Immunoglobulin G ; Interleukin-3 Receptor alpha Subunit ; Lupus Erythematosus, Systemic ; Pemphigus