Cold agglutinins(CA),autoantibodies against the antigen I or i on the surface of red blood cells,are mainly of IgM class,and the majority have κ light chains.They can lead to red blood cell agglutination at decreased body temperature and are usually associated with infections,drug reactions,autoimmune diseases,and hematological malignancies.However,solid tumors with CA are rare.We reported two cases of CA in the peripheral blood of patients with solid tumors.Peripheral complete blood cell count of the patients at admission showed reduced erythrocyte count and hematocrit,mismatching between erythrocyte count and hemoglobin,abnormally elevated levels of mean corpuscular hemoglobin and mean cell hemoglobin concentration.Peripheral blood smear showed erythrocyte aggregation.After the sample was preheated at 37 ℃ for 30 min,the reversibility of red blood cell aggregation was observed,and the erythrocyte parameters were corrected.
Humans ; Autoantibodies/isolation & purification* ; Female ; Breast Neoplasms/immunology* ; Ovarian Neoplasms/immunology*

Objective: To assess the correlation of glomerular C1q or IgA deposition with clinical and pathological features of primary membranous nephropathy (PMN) in children. Methods: The clinical and pathological manifestations including (phospholipase A2 receptor, PLA2R) and IgG subclasses staining in renal biopsies, serum anti-PLA2R antibody and therapeutic response of 33 children diagnosed with PMN in Peking University First Hospital from December 2012 to December 2020 were retrospectively summarized and analyzed. According to results of PLA2R test and findings renal pathological, the patients were divided into PLA2R-related group and non-PLA2R-related group, typical MN group and atypical MN group, C1q deposit group and non-C1q deposit group, as well as IgA deposit group and non-IgA deposit group respectively. T-test, Mann-Whitney U test and Fisher's exact probability test were used for comparison between the groups. Results: Among the 33 children with PMN, there were 20 males and 13 females, of that the age of onset was 11 (8, 13) years, and 32 patients had nephrotic level proteinuria. Renal biopsies were performed at 4.6 (2.1, 11.6) months after onset, and 28 patients (85%) received glucocorticoid or immunosuppressive therapy prior to renal biopsy. There were 20 cases (61%) with PLA2R-related MN and 13 cases (39%) with non-PLA2R-related MN. Compared with the non-PLA2R-related group, the PLA2R-related group had an older age of onset (12 (10, 13) vs. 7 (3, 12) years, Z=-2.52, P=0.011), a lower preceding infection rate (45% (9/20) vs. 11/13, P=0.032) and lower spontaneous remission rate (0 vs. 4/13, P=0.017). Renal PLA2R positivity was significantly associated with predominant or co-deposition of IgG4 (13/17 vs. 5/15, P=0.031) and low albumin levels at renal biopsy ((25±6) vs. (29±7) g/L, t=2.14, P=0.041). There were 12 patients with typical PMN and 21 patients with atypical PMN, and no significant difference in clinical and pathological manifestations was found between these 2 groups (all P>0.05). There were 10 cases (32.3%) with glomerular C1q deposition, and their disease course before renal biopsy was significantly shorter than those without C1q deposition (1.8 (0.8, 5.9) vs. 6.0 (2.5, 22.3) months, Z=-2.27, P=0.023). Twelve cases (36.4%) had glomerular IgA deposition, and their course of disease,clinical and pathological manifestations were not significantly different from those without IgA deposition (all P>0.05). Conclusion: Glomerular C1q or IgA deposition may not affect the clinical manifestations, glomerular PLA2R and IgG subclasses staining pattern, or the response to treatment of PMN in children.
Autoantibodies ; Child ; Complement C1q/metabolism* ; Female ; Glomerulonephritis, Membranous/drug therapy* ; Humans ; Immunoglobulin A/immunology* ; Immunoglobulin G ; Kidney Glomerulus ; Male ; Retrospective Studies

Immunotherapy has become the fourth cancer therapy after surgery, chemotherapy, and radiotherapy. In particular, immune checkpoint inhibitors are proved to be unprecedentedly in increasing the overall survival rates of patients with refractory cancers, such as advanced melanoma, non-small cell lung cancer, and renal cell carcinoma. However, inhibitor therapies are only effective in a small proportion of patients with problems, such as side effects and high costs. Therefore, doctors urgently need reliable predictive biomarkers for checkpoint inhibitor therapies to choose the optimal therapies. Here, we review the biomarkers that can serve as potential predictors of the outcomes of immune checkpoint inhibitor treatment, including tumor-specific profiles and tumor microenvironment evaluation and other factors.
Autoantibodies ; blood ; immunology ; Biomarkers, Tumor ; blood ; immunology ; Humans ; Immunotherapy ; Neoplasms ; blood ; therapy ; Tumor Microenvironment

Leucine-rich glioma-inactivated protein 1(LGI1)antibody-associated encephalitis is an autoimmune brain disease mainly seen in mid-aged and elderly people.Its main clinical manifestations include abnormal mental behaviors,facial-arm dystonia,hyponatremia,and hypokalemia.Immunotherapy with gamma globulin and/or hormone is effective.Two patients with LGT1 antibody-associated encephalitis were diagnosed in our center between January 2018 and October 2018,with typical clinical findings.The disease was cursed after immunoglobulin and hormone treatments.
Autoantibodies ; immunology ; Encephalitis ; diagnosis ; therapy ; Humans ; Proteins ; immunology

Systemic lupus erythematosus(SLE)is a chronic autoimmune disease that involves multiple organs and tissues.Its pathogenic mechanism remains unclear.Impaired inflammatory response and reduced clearance of immune cells are key events in the development of SLE,during which the pentraxin family plays an important role.This article summarizes recent advances in the relationship between anti-C-reactive protein autoantibody and SLE.
Autoantibodies ; immunology ; C-Reactive Protein ; immunology ; Humans ; Lupus Erythematosus, Systemic ; immunology

Objective To explore the clinical characteristics of autoimmune disease with dual seropositive antibodies of leucine-rich glioma inactivated 1(LGI1)and contactin-associated protein 2(Caspr2).Methods The clinical data of seven patients with dual seropositive LGI1 and Caspr2 antibodies who were admitted to the Neurology Department of Peking Union Medical College Hospital from July 2014 to December 2017 were retrospectively analyzed.Results Central,peripheral and autonomic nervous systems were all involved in the seven cases;100%(7/7)presented with insomnia,myokymia,neuropahic pain and hyperhydrosis;71%(5/7)showed memory decline or psychiatric and behavioral symptoms;57%(4/7)had urinary hesitation or constipation;and 43%(3/7)had seizure.Electromyography showed 100%(6/6) of the patients had prolonged afterdischarges following normal M waves and/or abnormal spontaneous firing.Electroencephalography revealed slow waves or basic rhythm slowing in 71%(5/7)of patients.Electrocardiography showed sinus tachycardia,axis deviation,and prolonged QT intervals in 71%(5/7)of patients.One patient died from arrhythmia before immunotherapy.One died from pulmonary infection after immunotherapy.Improvement with immunotherapy was documented in the other five cases.No relapse was noted during the 1-2-year follow-up.Conclusions Autoimmune disease with dual seropositive antibodies of LGI1 and Caspr2 can diffusely affect the central,peripheral,and autonomic nervous systems.The possibility of this disease should be considered in patients with acute and subacute onset of neuropsychiatric symptoms,especially in patients with accompanying insomnia,myokymia,and hyperhydrosis.
Autoantibodies ; blood ; Autoimmune Diseases ; immunology ; Humans ; Membrane Proteins ; immunology ; Nerve Tissue Proteins ; immunology ; Proteins ; immunology ; Retrospective Studies

BackgroundIncreased serum autoantibodies against interleukin-2 (anti-IL-2 autoantibodies) were reported in patients with systemic lupus erythematosus (SLE) and in patients receiving IL-2 therapy. This study aimed to explore the clinical relevance of serum anti-IL-2 autoantibodies and the interactions between low-dose IL-2 therapy and serum anti-IL-2 autoantibodies.

MethodsSerum samples were collected from 152 SLE patients and 100 age- and gender-matched healthy controls (HCs). Among them, 75 SLE patients were followed up for 10 weeks, and all of them were treated with corticosteroids, antimalarials, and/or immunosuppressants. Forty-six out of the 75 SLE patients received low-dose IL-2 therapy additionally. Clinical and laboratory parameters were collected at baseline and week 10. Serum anti-IL-2 autoantibodies were determined by enzyme-linked immunosorbent assay.

ResultsCompared with HCs, median levels and positive rates of serum anti-IL-2 autoantibodies were higher in SLE patients (32.58 [23.63, 45.23] arbitrary unit [AU] vs. 37.54 [27.88, 60.74] AU, P = 0.006, and 5.0% vs. 18.4%, P = 0.002, respectively). Compared to those without the corresponding disorders, serum anti-IL-2 autoantibody was increased in patients with alopecia (49.79 [36.06, 64.95] AU vs. 35.06 [25.40, 58.46] AU, P = 0.033), but it was decreased in those with lupus nephritis (31.71 [22.60, 43.25] AU vs. 44.15 [31.43, 68.52] AU, P = 0.001). Moreover, serum anti-IL-2 autoantibody was positively correlated with serum IgA (r = 0.229, P = 0.005), total IgG (r = 0.327, P < 0.001), and total IgM (r = 0.164, P = 0.050). Treatment with exogenous IL-2 was not significantly associated with serum anti-IL-2 autoantibody. In addition, no significant difference was found in serum anti-IL-2 autoantibody between responders and nonresponders to low-dose IL-2 therapy.

ConclusionsSerum anti-IL-2 autoantibody was increased and associated with disease severity in SLE. Exogenous low-dose IL-2 did not significantly induce anti-IL-2 autoantibody production.

Adult ; Autoantibodies ; Enzyme-Linked Immunosorbent Assay ; Female ; Humans ; Interleukin-2 ; immunology ; Lupus Erythematosus, Systemic ; immunology ; Lupus Nephritis ; Male ; Middle Aged ; Young Adult

Systemic lupus erythematous (SLE) is a systemic autoimmune disease with multi-organ inflammation caused by the production of pathogenic autoantibodies and immune complexes reflecting a global loss of tolerance. Lupus nephritis (LN) is present in approximately 60% of SLE patients and is considered a major predictor of a poor prognosis. To date, many studies utilizing genomics, transcriptomics, epigenetics, metabolomics, and microbiome have been conducted on a range of animal models and lupus patients to understand the pathogenesis of SLE and LN. Collectively, these studies support the concept that LN is caused by increased cell death, which has not been properly dealt with; abnormal innate immunity; hyperactive adaptive immunity; and genetic variants triggered by a range of environmental factors. This review summarizes the results from studies that contributed strongly to elucidating the pathogenesis of SLE and LN, highlighting the immunological and non-immunological mechanisms.
Adaptive Immunity ; Allergy and Immunology ; Antigen-Antibody Complex ; Apoptosis ; Autoantibodies ; Autoimmune Diseases ; Cell Death ; Epigenomics ; Genomics ; Humans ; Immunity, Innate ; Inflammation ; Lupus Nephritis* ; Lymphocytes ; Metabolomics ; Microbiota ; Models, Animal ; Prognosis ; Wolves*

OBJECTIVE: To investigate the clinical characteristics of rheumatoid arthritis (RA) patients with malignant tumor. METHODS: Retrospective summary was made of 1 562 in patients of RA from January 2011 to June 2017. In the study, 74 RA patients with malignant tumor were reviewed and analyzed, and the general conditions, tumor types, RA and tumor onset sequence, and the medication situation were analyzed. RESULTS: The incidence of malignant tumor in the patients with rheumatoid arthritis in our center was 4.16%. The 74 patients were complicated with malignant tumor, of whom 53 were female, and 21 male. The age of RA at presentation was (52.6±17.8) years. The average disease duration of malignant tumor was (63.4 ± 12.7) years. The onset time of rheumatoid arthritis was earlier than that of malignant tumors in 51 cases (51/74), with an average of (17.2±14.2) years between 2 and 60 years. The incidence of malignant tumor was earlier than that of rheumatoid arthritis in 16 cases (16/74), with an average of (6.2±5.9) years between 1 and 21 years, of which 10 cases were sex hormone related tumors. Seven cases (7/74) were diagnosed with RA at the same time, and the time interval between the two diseases was within 1 year. All the patients were over 60 years old with digestive tract tumors. All the 7 patients showed polyarthritis, significantly increased erythrocyte sedimentation rate and C-reactive protein, including 4 rheumatoid factor positive cases and 2 anti-CCP antibody positive cases. The effect of non-steroidal anti-inflammatory drugs and traditional drugs to improve the condition of the disease was poor in the 7 patients, and the condition was relieved after using low-dose glucocorticoids. Gastrointestinal tumors, breast and reproductive system tumors were the most common, followed by respiratory, urological and blood system tumors. CONCLUSION The risk in patients of rheumatoid arthritis complicated with malignant tumor is higher than that of the general population. A variety of factors play an important role in cancer risk of RA, including disease activity, some estrogen metabolites, the use of drugs and so on. Therefore, all RA patients should be screened for malignant tumor during diagnosis, and malignant tumor surveillance is mandatory for all rheumatoid arthritis patients after diagnosis.
Adult ; Aged ; Arthritis, Rheumatoid/complications* ; Autoantibodies ; C-Reactive Protein/analysis* ; Female ; Humans ; Male ; Middle Aged ; Neoplasms/immunology* ; Peptides, Cyclic ; Retrospective Studies ; Rheumatoid Factor/blood*

Systemic lupus erythematosus (SLE) is a highly heterogeneous autoimmune disease, characterized by production of pathogenic autoantibodies and wide involvement of multiple systems. Damageofimmune tolerance and imbalance of immune homeostasis lead to the production of autoantibodies and the injuries of multiple organs and systems. In recent years, plenty of studies have identified that immunometabolism affects survival status of certain cells, also cell activation, differentiation and effector functions. Conversely, immune cells with different functions or differentiational status upregulate specific metabolic pathways to maintain their identities. In response to outer stimulations, naive immune cells differentiate into activated cells, accompanied with a series of immunometabolism changes. Therefore, abnormal immunometabolism can induce global imbalance of immune homeostasis, which further results in the initiation and development of autoimmune diseases, including SLE. Multiple abnormalities of immunometabolism have been found in patients with SLE or mouse models of lupus. Immune cells involved in the development of SLE, such as T cells, B cells, dendritic cells and macrophages present various metabolic abnormalities and pathological phenotypes. Among these cells, CD4+ T cells play predominant roles in the pathogenesis of SLE. Lots of studies demonstrated that CD4+ T cells and their subsets were in abnormal immunometabolic status,which further resulted in the development of SLE. In CD4+ T cells from patients with SLE or mouse models of lupus, both levels of glycolysis and oxidative phosphorylation are significantly higher compared with healthy controls. However,mitochondrial abnormalities, decreased ATP production and increased level of oxidative stress also have been found in these cells, which play important roles in the production of reactive oxygen intermediates and autoantibodies. Aggregated lipids rafts and increased synthesis of glycosphingolipid and cholesterol also have been observed in the CD4+ T cells from patients with SLE, leading to the abnormally elevated TCR signaling. Moreover, mechanistic target of rapamycin (mTOR) signaling is activated in the CD4+ T cells from both patients with SLE or mouse models of lupus and participate in the metabolic abnormalities of pathological CD4+ T cells. Progressive understanding of immunometabolism give us new insights of the pathogenesis of SLE and provide us with more therapeutic targets in the treatment of SLE.
Animals ; Autoantibodies ; CD4-Positive T-Lymphocytes ; Cell Differentiation ; Humans ; Lupus Erythematosus, Systemic/immunology* ; Mice ; Signal Transduction