Study on the Treatment of ITP Mice with IVIG Sourced from Distinct Sex-Special Plasma (DSP-IVIG).

Intravenous immunoglobulin (IVIG) is a first-line drug prepared from human plasma for the treatment of autoimmune diseases (AIDs), especially immune thrombocytopenia (ITP). Significant differences exist in protein types and expression levels between male and female plasma, and the prevalence of autoimmune diseases varies between sexes. The present study seeks to explore potential variations in IVIG sourced from distinct sex-specific plasma (DSP-IVIG), including IVIG sourced from female plasma (F-IVIG), IVIG sourced from male plasma (M-IVIG), and IVIG sourced from a blend of male and female plasma (Mix-IVIG). To address this question, we used an ITP mouse model and a monocyte-macrophage inflammation model treated with DSP IVIG. The analysis of proteomics in mice suggested that the pathogenesis and treatment of ITP may involve FcγRs mediated phagocytosis, apoptosis, Th17, cytokines, chemokines, and more. Key indicators, including the mouse spleen index, CD16+ macrophages, M1, M2, IL-6, IL-27, and IL-13, all indicated that the efficacy in improving ITP was highest for M-IVIG. Subsequent cell experiments revealed that M-IVIG exhibited a more potent ability to inhibit monocyte phagocytosis. It induced more necrotic M2 cells and fewer viable M2, resulting in weaker M2 phagocytosis. M-IVIG also demonstrated superiority in the downregulation of surface makers CD36, CD68, and CD16 on M1 macrophages, a weaker capacity to activate complement, and a stronger binding ability to FcγRs on the THP-1 surface. In summary, DSP-IVIG effectively mitigated inflammation in ITP mice and monocytes and macrophages. However, M-IVIG exhibited advantages in improving the spleen index, regulating the number and typing of M1 and M2 macrophages, and inhibiting macrophage-mediated inflammation compared to F-IVIG and Mix-IVIG.

Parvovirus B19 DNA and antibodies in Chinese plasma donors, plasma pools and plasma derivatives.

Background: Human parvovirus B19 (B19V) is a common contaminant found in plasma pools and plasma derivatives. Previous studies were mainly focused on limited aspects, further assessment of prevalence of B19V DNA and antibodies in plasma donors, the contamination of B19V in pooled plasma and plasma derivatives should be performed in China. Study Design and Methods: Individual plasma donors' samples from four provinces and pooled plasma from four Chinese blood product manufacturers were collected and screened using B19V DNA diagnostic kits between October 2018 and May 2020. The positive samples were investigated for the seroprevalence of B19V antibodies and subjected to sequence analysis and alignment for phylogenetic studies. Moreover, 11 plasma donors who were B19V DNA-positive at their first testing were also followed during the later donation period. Additionally, 400 plasma pools and 20 batches of plasma derivatives produced by pooled plasma with a viral load of B19V DNA exceeding 104IU/mL were also collected and tested for B19V DNA and antibodies. Objectives: To comprehensively and systematically determine the frequency and viral load of B19V DNA in plasma donors, pooled plasma, and plasma derivatives from four Chinese blood product manufacturers. Results: A total of 17,187 plasma donors were analyzed and 44 (0.26%) specimens were found positive for B19V DNA. The quantitative DNA levels ranged from 1.01 × 101 to 5.09 × 1012 IU/mL. Forty-four DNA-positive specimens were also investigated for the seroprevalence of B19V antibodies, 75.0% and 2.3% of which were seropositive for B19V IgG and IgM antibodies, respectively. The phylogenic analyses showed that the prevalent genotypes in the four provinces' plasma donors belonged to B19V Genotype 1. Eleven individual plasma donors who were B19V DNA-positive at the first donation were then followed for a period, and in general, the DNA levels of B19V gradually decreased. Moreover, 64.8% (259/400) of the pooled plasma was contaminated by B19V, with concentrations of 1.05 × 100-3.36 × 109IU/mL. Approximately 72.6% of the DNA-positive plasma pools were only moderately contaminated (<104 IU/mL), while 27.4% contained >104 IU/mL. Twenty batches of plasma derivatives produced by pooled plasma with a viral load of B19V DNA exceeding 104IU/mL were also tested. B19V was detected in 5/5 PCC samples and 5/5 factor VIII samples but was not found in the intravenous immune globulin and albumin samples. Conclusion: The contamination of B19V in pooled plasma and plasma-derived clotting factor concentrates is serious. Whether B19V nucleic acid testing (NAT) screening of plasma and plasma derivatives is launched in China, blood product manufacturers should spontaneously perform B19V NAT screening in plasma donors and mini-pool plasma. These measures can ensure that samples with high titer B19V DNA are discarded in order to prevent and control this transfusion transmitted virus.

Blood Service in a Region of China's Qinghai-Tibetan Plateau.

Objectives: The purpose of this paper is to describe blood services in the Aba Tibetan and Qiang Regions, (hereinafter referred to as Aba Prefecture), a region of China's Qinghai-Tibetan Plateau, the third largest area of Tibet and the main inhabited area of the Qiang people. Design: We present a comprehensive investigation into blood donations, donors, screening and supply in the 13 counties of Aba Prefecture based on data from 2013 to 2018. Geography and population were also used to analyze the differences in blood services among different regions. Participants: The number of blood donors totaled 19,047. Results: Over the past 6 years, blood donations have increased by 29 and clinical blood usage by 45%. The blood donation rate was 3.4‱ and per capita blood use was 1.04 mL, both of which were significantly lower than the national average, and blood donation decreased with altitude. It should be noted that the donation rate of the Tibetan and Qiang peoples is much lower than that of the Han population. Moreover, the rejection rate of blood in laboratory testing was found to be higher than the national average, especially in counties located at higher altitudes. Conclusions: Blood donations and usage increased every year in Aba Prefecture, but blood shortage is still an important issue. In addition, the prevalence of transfusion-transmitted diseases is relatively high, which may be linked to lower-education and unfavorable geographical and medical conditions.

Antibody Assay and Anti-Inflammatory Function Evaluation of Therapeutic Potential of Different Intravenous Immunoglobulins for Alzheimer's Disease.

Alzheimer's disease (AD) is a common neurodegenerative disease that currently has no known cure. Intravenous immunoglobulin (IVIG), which contains AD-related antibodies and has anti-inflammatory properties, has shown potential as a treatment for AD. However, the efficacy of clinical trials involving AD patients treated with IVIG has been inconsistent. Our previous study found that different IVIGs had significantly varied therapeutic effects on 3xTg-AD mice. In order to investigate the relationship between the composition and function of IVIG and its efficacy in treating AD, we selected three IVIGs that showed notable differences in therapeutic effects. Then, the concentrations of specific antibodies against ß-amyloid (Aß)42, tau, and hyperphosphorylated tau (p-tau) in three IVIGs, as well as their effects on systemic inflammation induced by lipopolysaccharide (LPS) in Balb/c mice, were analyzed and compared in this study. The results indicated that these IVIGs differed greatly in anti-Aß42/tau antibody concentration and anti-p-tau ratio, and improved LPS-stimulated peripheral inflammation, liver and kidney injury, and neuroinflammation in Balb/c mice to varying degrees. Combined with our previous results, the efficacy of IVIG against AD may be positively correlated with its level of AD-related antibodies and anti-inflammatory ability. AD-related antibody analysis and functional evaluation of IVIG should be given sufficient attention before clinical trials, as this may greatly affect the therapeutic effect of AD treatment.

Analysis of influencing factors of serum total protein and serum calcium content in plasma donors.

Background and objectives: The adverse effects of plasma donation on the body has lowered the odds of donation. The aim of this study was to investigate the prevalence of abnormal serum calcium and total serum protein related to plasma donation, identify the influencing factors, and come up with suggestions to make plasma donation safer. Methods: Donors from 10 plasmapheresis centers in five provinces of China participated in this study. Serum samples were collected before donation. Serum calcium was measured by arsenazo III colorimetry, and the biuret method was used for total serum protein assay. An automatic biochemical analyzer was used to conduct serum calcium and total serum protein tests. Results: The mean serum calcium was 2.3 ± 0.15 mmol/L and total serum protein was 67.75 ± 6.02 g/L. The proportions of plasma donors whose serum calcium and total serum protein were lower than normal were 20.55% (815/3,966) and 27.99% (1,111/3,969), respectively. There were significant differences in mean serum calcium and total serum protein of plasma donors with different plasma donation frequencies, gender, age, regions, and body mass index (BMI), (all p < 0.05). Logistic regression analysis revealed that donation frequencies, age, BMI and regions were significantly associated with a higher risk of low serum calcium level, and donation frequencies, gender, age and regions were significant determinants factors of odds of abnormal total serum protein. Conclusions: Donation frequencies, gender, age, regions, and BMI showed different effects on serum calcium and total serum protein. More attention should be paid to the age, donation frequency and region of plasma donors to reduce the probability of low serum calcium and low total serum protein.

Proteomics profiles of blood glucose-related proteins involved in a Chinese longevity cohort.

BACKGROUND: High blood glucose level is one of the main characteristics of diabetes mellitus. Based on previous studies, it is speculated longevity families may have certain advantages in blood glucose regulation. However, limited information on these items has been reported. The purpose of this study was to profile differences of plasma proteomics between longevity subjects (with normal fructosamine (FUN) level) and non-longevity area participants (with exceeding standard FUN level). METHODS: In this study, a TMT-based proteomics analysis was used to profile differences of plasma proteomics between longevity subjects (with normal FUN level) and non-longevity area participants (with exceeding standard FUN level). Results were validated by Luminex detection. RESULTS: A total of 155 differentially expressed proteins (DEPs) were identified between these two groups. The DEPs related to blood glucose regulation were mainly involved in glycolysis/gluconeogenesis, pyruvate metabolism and propanoate metabolism, and most of the DEPs were contained in carbohydrate metabolism, PI3K-Akt pathway, glucagon signaling pathway and inflammatory response. Validation by Luminex detection confirmed that CD163 was down-regulated, and SPARC, PARK 7 and IGFBP-1 were up-regulated in longevity participants. CONCLUSIONS: This study not only highlighted carbohydrate metabolism, PI3K-Akt pathway, glucagon signaling pathway and inflammatory response may play important roles in blood glucose regulation, but also indicated that YWHAZ, YWHAB, YWHAG, YWHAE, CALM3, CRP, SAA2, PARK 7, IGFBP1 and VNN1 may serve as potential biomarkers for predicting abnormal blood glucose levels.

GDF11 Regulates PC12 Neural Stem Cells via ALK5-Dependent PI3K-Akt Signaling Pathway.

Growth differentiation factor 11 (GDF11), belonging to the transforming factor-ß superfamily, regulates anterior-posterior patterning and inhibits neurogenesis during embryonic development. However, recent studies recognized GDF11 as a rejuvenating (or anti-ageing) factor to reverse age-related cardiac hypertrophy, repair injured skeletal muscle, promote cognitive function, etc. The effects of GDF11 are contradictory and the mechanism of action is still not well clarified. The objective of the present study was to investigate effects of GDF11 on PC12 neural stem cells in vitro and to reveal the underlying mechanism. We systematically assessed the effects of GDF11 on the life activities of PC12 cells. GDF11 significantly suppressed cell proliferation and migration, promoted differentiation and apoptosis, and arrested cell cycle at G2/M phase. Both TMT-based proteomic analysis and phospho-antibody microarray revealed PI3K-Akt pathway was enriched when treated with GDF11. Inhibition of ALK5 or PI3K obviously attenuated the effects of GDF11 on PC12 neural stem cells, which exerted that GDF11 regulated neural stem cells through ALK5-dependent PI3K-Akt signaling pathway. In summary, these results demonstrated GDF11 could be a negative regulator for neurogenesis via ALK5 activating PI3K-Akt pathway when it directly acted on neural stem cells.

The proteome profiling of EVs originating from senescent cell model using quantitative proteomics and parallel reaction monitoring.

Senescence is the inevitable biological processes and is also considered as the biggest risk factor for the development of age - related diseases (ARDs) and geriatric syndrome (GS). Senescence is also known as inflammaging because it is characterized by persistent, long-term, low-grade inflammation named senescence-associated secretory phenotype (SASP). However, the mechanism for the persistence of inflammaging remains largely unclear. To explore the role of extracellular vesicles (EVs) in senescence/inflammaging, we established the cellular senescence model and performed TMT-based comparative quantitative proteomics and parallel reaction monitoring (PRM) to reveal the changes of EVs between young cells and senescent cells. A total of 3966 proteins were quantifiable, of which 132 were up-regulated, 144 were down-regulated, compared with the young cells. Subsequently, we chose 19 proteins involved in inflammation or proliferation to carry out PRM validation analysis. The result indicated that proteins promoting NF-κB signal pathway were up-regulated, and proteins promoting cell proliferation were down-regulated. The study provided a comprehensive altered proteomics profiles of EVs from senescent cells, and the result showed that EVs could serve as information carrier for further research on the pathogenesis and progression of senescence/inflammaging. SIGNIFICANCE: The mechanism of inflammaging occurrence and development has yet been clear. Therefore, this study attempts to provide an improved understanding of inflammaging from the perspective of EVs. The proteomics analysis revealed that the most changed proteins were connected to inflammation signaling pathways, cell growth and cell death, and PRM analysis results showed that proteins involved in NF-κB signal pathway and cell proliferation were more changed. The research systematically analyzed the profiles of proteins in senescence cell model, and the result indicated that further research should focus on the relationship between EVs and senescence/inflammaging.

In vitro Aggregation Ability of Five Commercially Available Aß42 peptide.

BACKGROUND: As the most basic material, synthetic human Amyloid-ß (1-42) (Aß42) peptide from different manufacturers have been widely used. Their aggregation ability is vital to the reliability, repeatability and comparability of studies on Aß42 physiology and pathology. However, it has not been evaluated and compared. OBJECTIVE: To analyze the consistency of the aggregation ability of 5 commercially available Aß42 peptide. METHODS: 5 Aß42 peptide represented as A, B, C, D and E were pretreated by HFIP. The pretreated Aß42 peptide were dissolved in Thioflavin T (ThT) solution, and their aggregation kinetics was monitored for 30 h with the aggregation kinetics test. Meanwhile, the pretreated peptide were aggregated in phosphate buffered saline. After aggregated for 12 h, they were detected by methods of ThT fluorescence, far-UV circular dichroism (CD), SDS-PAGE, western blot, and transmission electron microscopy (TEM), respectively. After aggregation for 8 h and 12 h, their cytotoxicity to SH-SY5Y cells was further evaluated using Cell Counting Kit-8. RESULTS: For aggregation kinetics, peptide A, C and E remained low level curves, while peptide B and D presented typical sigmoidal kinetics curves. In CD measurement, the aggregates of peptide B and D showed relatively high negative CD peaks with the height of -8.09 mdeg and -14.37 mdeg, while the height of peptide A, C and E was -1.04, -3.55, and -3.88. In ThT assay, relative fluorescence intensity of the aggregates of peptide B and D were 7.79 and 8.82, higher than 1.19, 1.71, and 2.70 of peptide A, C and E, respectively. In SDS-PAGE, all aggregates contained monomers and eleven polymers. Moreover, peptide B-E presented a trapezoidal distribution from dimers to trimers, and peptide A aggregated to dimers. By western blot, the bands of monomers remained in all aggregates. Furthermore, peptide B and D aggregated to dimers and trimers, peptide A and C only aggregated to dimers, and peptide E showed a strong band of trimers. By TEM, protofibrils were observed only in peptide B, while substantial spherical aggregates were formed in other peptide. Additionally, peptide B, D and E exhibited higher cytotoxicity after aggregated for 8 h, whereas peptide A, B and D presented relatively high cytotoxicity after 12-hour aggregation. CONCLUSION: Commercially available Aß42 peptide showed obvious differences in aggregation ability, which should arouse enough attention in the field of basic study related to Aß42. The aggregation ability evaluation with the various assay methods has some discrepancies, and it is highly urgent to establish a reasonable and uniform measurement strategy.

Demographic Characteristics and Lifestyle Habits of Chinese Plasma Donors: A Multicenter Study.

BACKGROUND The demand for plasma and plasma products has increased in China, which has a short supply. Compared with whole blood donors, plasma donors and their donation behavior have received less attention. This study aimed to investigate the demographic characteristics and lifestyle habits of Chinese plasma donors. MATERIAL AND METHODS During 2018-2019, information on plasma donors was collected from blood product companies using a 25-item questionnaire, including sex, age, height, weight, blood group, donation frequency, occupation, smoking and drinking, and sleeping and dietary habits. RESULTS Among 15 497 plasma donors, 70.5% were women and 78.5% were aged 46-55 years. Among 4847 plasma donors, the average height of men was 169.5±6.2 cm and the average height of women was 157.0±4.6 cm. In addition, the average weight of men was 67.0±10.4 kg and the average weight of women was 60.0±8.3 kg. The prevalence of obesity (body mass index ≥30.0 kg/m²) of all donors was 14.8%; 14.7% of men were obese, and 15% of women were obese. Among all plasma donors, 88.8% were farmers and 60% were frequent donors with a donation history of at least 5 years. Among all donors, 84.0% did not smoke, 67.3% did not drink, and 95.1% reported good sleep quality. All respondents reported healthy dietary habits. CONCLUSIONS Healthy lifestyle habits considerably affect the health of plasma donors and the quality of source plasma. Chinese plasma donors in this study demonstrated imbalances in terms of characteristics, which became more marked with age.

Effects of long-term high-altitude exposure on fibrinolytic system.

OBJECTIVE: High altitude (HA), with the main feature of hypobaric hypoxia, is an independent risk factor for thrombosis. However, little is known on the alterations of fibrinolytic system in adaptation to HA. In this study, we investigated changes of fibrinolytic system parameters between individuals permanently living at HA and low altitude (LA) regions, and provided data for further studies on HA-induced thrombotic disease. MATERIAL AND METHODS: A total of 226 eligible participants, including 103 LA participants, 100 healthy HA subjects and 23 high altitude polycythemia (HAPC) patients, were recruited in this study. Six fibrinolytic parameters, i.e. fibrinogen (Fbg), D-dimer (DDi), antithrombin III (AT-III), plasminogen activator inhibitor-1 (PAI-1), tissue plasminogen activator (tPA) and plasminogen (PLG) were analyzed respectively. PAI-1 and tPA were performed by using bio-immuno-assays and an automated coagulation analyzer was used to conduct Fbg, DDi, AT-III and PLG tests. RESULTS: Plasma levels of Fbg, DDi, PAI-1 and PLG were significantly higher in healthy HA group than in LA group (all p < 0.05), whereas tPA was significantly lower in healthy HA group. No significant difference in AT-III was observed between healthy HA and LA groups (p > 0.05). All these fibrinolytic parameters showed no significant distinctions between healthy HA subjects and HAPC patients (all p > 0.05). HGB showed no relationship with fibrinolytic parameters in HA cohort. CONCLUSION: This study demonstrates that HA environment has a significant effect on fibrinolytic system and provides a foundation for further studies on HA hypobaric hypoxia-induced thrombotic disease.

Content of anti-ß-amyloid42 oligomers antibodies in multiple batches from different immunoglobulin preparations.

Immunoglobulin preparations are one of the promising drugs for Alzheimer's disease (AD). Anti-ß-amyloid (Aß) oligomers antibodies in immunoglobulin preparations are considered to be critical for the therapeutic effect against Alzheimer's disease. However, the antibodies content in immunoglobulin preparations varies greatly. In order to determine which factor contributes to the difference of the antibodies content, the content of anti-Aß oligomers antibodies in multiple batches of immunoglobulin preparations from two manufacturers were measured by enzyme-linked immunosorbent assay. The results showed that no significant difference was found in the antibodies content among different bathes of normal immunoglobulin preparations prepared by the same process from the same manufacturer, whereas significant difference was found in the antibodies content between normal immunoglobulin preparations prepared by ethanol fractionation and those by chromatography process from the same manufacturer. In addition, significant variation existed in the antibodies content between normal immunoglobulin preparations and specific immunoglobulin preparations that are produced by plasma pool of immunized donors. Based on analysis of these results, the preparation process and raw plasma could be the main contributing factors affecting the content of anti-Aß oligomers antibodies in immunoglobulin preparations. This finding might help to develop AD-specific immunoglobulin preparation containing higher content of anti-Aß oligomers antibodies.

Plasma proteomic and autoantibody profiles reveal the proteomic characteristics involved in longevity families in Bama, China.

BACKGROUND: Chinese Bama Yao Autonomous County is a well-known longevity region in the world. In the past 30 years, population and genome studies were undertaken to investigate the secret of longevity and showed that longevity is the result of a combination of multiple factors, such as genetic, environmental and other causes. In this study, characteristics of the blood plasma proteomic and autoantibody profiles of people from Bama longevity family were investigated. METHODS: Sixty-six plasma donors from Chinese Bama longevity area were recruited in this study. Thirty-three offsprings of longevous families were selected as case studies (Longevous group) and 33 ABO (blood type), age, and gender-matched subjects from non-longevous families were selected as controls (Normal group). Each group contains 3 biological replicates. Tandem mass tag-based proteomic technique was used to investigate the differentially expressed plasma proteins between the two groups. The auto-reactive IgG antibody profiles of the 3 pooled samples in each group were revealed by human proteome microarrays with 17,000 recombinant human proteins. RESULTS: Firstly, 525 plasma proteins were quantified and 12 proteins were discovered differentially expressed between the two groups. Secondly, more than 500 proteins were recognized by plasma antibodies, 14 proteins ware differentially reacted with the autoantibodies in the two groups. Bioinformatics analysis showed some of the differential proteins and targeted autoantigens were involved in cancer, cardiovascular disease and immunity. CONCLUSIONS: Proteomic and autoantibody profiles varied between the offspring of longevous and normal families which are from the same area and shared the same environmental factors. The identified differences were reported to be involved in several physiological and pathological pathways. The identified proteins will contribute to a better understanding of the proteomic characteristics of people from Bama longevous area and a revelation of the molecular mechanisms of longevity.

Alterations of Human Plasma Proteome Profile on Adaptation to High-Altitude Hypobaric Hypoxia.

For individuals migrating to or residing permanently in high-altitude regions, environmental hypobaric hypoxia is a primary challenge that induces several physiological or pathological responses. It is well documented that human beings adapt to hypobaric hypoxia via some protective mechanisms, such as erythropoiesis and overproduction of hemoglobin; however, little is known on the alterations of plasma proteome profiles in accommodation to high-altitude hypobaric hypoxia. In the present study, we investigated differential plasma proteomes of high altitude natives and lowland normal controls by a TMT-based proteomic approach. A total of 818 proteins were identified, of which 137 were differentially altered. Bioinformatics (including GO, KEGG, protein-protein interactions, etc.) analysis showed that the differentially altered proteins were basically involved in complement and coagulation cascades, antioxidative stress, and glycolysis. Validation results demonstrated that CCL18, C9, PF4, MPO, and S100A9 were notably up-regulated, and HRG and F11 were down-regulated in high altitude natives, which were consistent with TMT-based proteomic results. Our findings highlight the contributions of complement and coagulation cascades, antioxidative stress, and glycolysis in acclimatization to hypobaric hypoxia and provide a foundation for developing potential diagnostic or/and therapeutic biomarkers for high altitude hypobaric hypoxia-induced diseases.

Correlation between RBC changes and coagulation parameters in high altitude population.

OBJECTIVE: To explore the correlations between RBCs indexes and the basic coagulation parameters, and provide data for further studies on high altitude-induced thrombotic disease. METHODS: A total of eligible 433 volunteers were divided into different groups according to HGB concentration and HCT, respectively. PT, APTT, TT and Fbg were measured by clotting assays. HGB content, HCT and PLT count were assessed by automated hematology analyzer. RESULTS: APTT and PT were significantly higher in group 4 (high HGB or HCT groups) (p < 0.05 for all comparison) and PLT count was significantly lower in group 4 than in other groups (p < 0.01 for all comparison). APTT and PT showed negative correlations with HGB concentration (r = -0.168 and -0.165 resp.; both p < 0.01), whereas positive correlations were found between APTT and HCT, PT and HCT (r = 0.225 and 0.258, resp.; both p < 0.01). PLT, TT and Fbg showed no correlation with HGB and HCT. CONCLUSIONS: HGB and HCT may not correlate with basic coagulation parameters in high altitude population, their predictive value for high altitude-induced thrombotic disease may relatively independent and this remain to be determined in further studies.

Plasma proteome profiling of high-altitude polycythemia using TMT-based quantitative proteomics approach.

High-altitude polycythemia (HAPC) is one of the classic chronic mountain sicknesses and has been a serious public health problem in high-altitude regions. Despite numerous studies on HAPC via genomics or transcriptomics approaches, the pathogenesis of HAPC is still unclear. Here, we performed a TMT- based comparative quantitative proteomics analysis to reveal the changes of plasma proteomics profiles between HAPC subjects and healthy controls. Of identified 818 proteins, 7 and 12 proteins were up-regulated and down-accumulated, respectively, compared HAPC patients with healthy controls. GO and KEGG pathway analyses revealed the dysregulated proteins were primarily involved in complement and coagulation cascades, inflammation and immune response. ELISA validation demonstrated that C4A, C6 and CALR were down-regulated, and MASP1 and CNDP1 were up-regulated in HAPC patients. By ROC analysis, combinations of these five proteins (i.e., C4A, C6, CALR, MASP1 and CNDP1) resulted in a high AUC value (0.919; 95% CI, 0.817-961; p < .0001) to diagnose HAPC patients. Moreover, CNDP1 seems to be a robust biomarker for HAPC. This study not only provided a comprehensive dataset on overall proteomics changes in HAPC patients compared with healthy controls, but also indicated that CNDP1 can serve as a strong plasma biomarker of HAPC for the diagnostic and therapeutic potential. SIGNIFICANCE: HAPC, one of the classic chronic mountain sicknesses, has been a serious public health problem in high-altitude regions. Despite numerous studies on HAPC via genomics or transcriptomics approaches, the pathogenesis of HAPC is still largely unknown to date. In this study, we addressed this issue by performing TMT-based quantitative analyses of the plasma proteome profiles of HAPC patients and healthy controls. We identified 818 proteins, of which 19 were differentially expressed. Bioinformatics analysis revealed the differentially expressed proteins were mainly involved in complement and coagulation cascades, inflammation and immune response. By ROC analysis, combinations of C4A, C6, CALR, MASP1 and CNDP1 resulted in a high AUC value (0.919, p < .0001) to distinguish HAPC patients from healthy controls. Collectively, the current study provided a comprehensive dataset on overall proteomic changes in HAPC patients for the first time, and it also revealed C4A, C6, CALR, MASP1 and CNDP1 can be served as candidate plasma biomarkers of HAPC for their diagnostic and therapeutic potential.

Effect of Different Aß Aggregates as Antigen on the Measure of Naturally Occurring Autoantibodies against Amyloid-ß40/42 in IVIG.

BACKGROUND: The specific Intravenous Immunoglobulin (IVIG) for Alzheimer's Disease (AD) is developing, which contains a high level of naturally occurring autoantibodies against amyloid-ß (nAbs-Aß), and the measure of nAbs-Aß content is greatly essential. Though Enzyme-Linked Immunosorbent Assay (ELISA) has been widely used in detecting the nAbs-Aß content, the impact of Aß aggregates species chosen as antigen in ELISA on this measure has not been evaluated. OBJECTIVE: To clarify the influence of different Aß40/42 aggregates as antigen during ELISA on the content of nAbs-Aß40/42 measured in IVIG. METHOD: Preparation of various Aß40/42 aggregates was performed by different aggregation solutions and various lengths of time, and analyzed by western blot. Different Aß40/42 aggregates as antigen were adopted to measure the nAbs-Aß40/42 content in IVIG by ELISA, and the control was carried out to reduce interference of nonspecific binding. The Bonferroni and Dunnett's T3 were used for statistical analysis. RESULTS: The duration for the formation of Aß40/42 aggregates had more effect on detecting nAbs-Aß40/42 content in IVIG than the aggregation solution. Higher content of nAbs-Aß40/42 in the same IVIG was displayed when measured with Aß40/42 aggregates at day 3, instead of at day 0.5 and day 7.0. The nAbs- Aß40/42 contents in the same IVIG measured with Aß40/42 aggregates prepared in different solutions were obviously different, but there was no significant regularity among them. CONCLUSION: The nAbs-Aß40/42 content in the same IVIG is significantly different when measured with Aß40/42 aggregated under different conditions. The nAbs-Aß40/42 content in IVIG by antigen-dependent measures, like ELISA, is uncertain.

TMT-Based Quantitative Proteomic Analysis Reveals Proteomic Changes Involved in Longevity.

PURPOSE: Individual lifespans vary widely, and longevity is the main concern from ancient to modern times. This study is aimed to identify plasma proteins associated with longevity by proteomics technique. EXPERIMENTAL DESIGN: Tandem mass tags (TMT)-based proteomics analysis is performed for the plasma of Bama longevity group and a control group to analyze the differentially expressed proteins (DEPs). A validation set is used to verify the results of TMT-based proteomics. RESULTS: Between Bama natives and the control individuals, the authors identify 175 DEPs, which are mainly involved in complement and coagulation cascades, metabolism of glyco and lipid, and regulation of actin cytoskeleton. Consistent with the proteomic analysis, plasma levels of MMP2, CCL5, and PF4 are significantly lower in Bama participants than in controls, whereas IGFBP2 and C9 increase in Bama individuals, in the validation set. By ROC analysis, combinations of these five proteins result in a high AUC value (0.991, 95% CI, 0.929-1.000, p < 0.0001) to distinguish longevous participants from controls. CONCLUSIONS AND CLINICAL RELEVANCE: The results highlight the roles of complement and coagulation cascades, metabolism of glyco and lipid, and inflammatory and immune response may play important roles in longevity. And the DEPs may serve as clinically useful biomarkers for healthy aging and predicting longevity.

Analysis of sialic acid levels in Chinese intravenous immunoglobulins by high-performance liquid chromatography with fluorescence detection.

Intravenous immunoglobulin (IVIg) is increasingly used for the treatment of autoimmune and systemic inflammatory diseases with both licensed and off-label indications. Recent studies indicated that IVIg-mediated immunomodulation and anti-inflammation are closely associated with the IgG sialylation, especially with IgG crystallizable fragment (Fc) sialylation. The sialic acid levels of the IgG molecules and Fc fragments in 12 IVIg preparations from six Chinese manufacturers were evaluated. The Fc fragments were derived from the papain digestion of IVIg, followed by affinity and size exclusion chromatography. The sialic acid levels in Fc fragments and IVIg preparations were determined by high-performance liquid chromatography with fluorescence detection, after the sialic acid residues were released from the proteins. The results showed that the sialic acid levels in Chinese IVIg preparations ranged from 0.875 (mol/mol IgG) to 1.085 (mol/mol IgG), and the sialic acid levels in Fc fragments were from 0.321 (mol/mol Fc) to 0.361 (mol/mol Fc). Furthermore, the sialic acid levels of IVIg preparations and Fc fragments from different Chinese manufactures were significantly different. These findings will contribute to an increased understanding of Chinese IVIg preparations and the relationship between the sialic acid levels in IVIg preparations and their clinical efficacy in future clinical studies.

GDF11 induces differentiation and apoptosis and inhibits migration of C17.2 neural stem cells via modulating MAPK signaling pathway.

GDF11, a member of TGF-ß superfamily, has recently received widespread attention as a novel anti-ageing/rejuvenation factor to reverse age-related dysfunctions in heart and skeletal muscle, and to induce angiogenesis and neurogenesis. However, these positive effects of GDF11 were challenged by several other studies. Furthermore, the mechanism is still not well understood. In the present study, we evaluated the effects of GDF11 on C17.2 neural stem cells. GDF11 induced differentiation and apoptosis, and suppressed migration of C17.2 neural stem cells. In addition, GDF11 slightly increased cell viability after 24 h treatment, showed no effects on proliferation for about 10 days of cultivation, and slightly decreased cumulative population doubling for long-term treatment (p < 0.05). Phospho-proteome profiling array displayed that GDF11 significantly increased the phosphorylation of 13 serine/threonine kinases (p < 0.01), including p-p38, p-ERK and p-Akt, in C17.2 cells, which implied the activation of MAPK pathway. Western blot validated that the results of phospho-proteome profiling array were reliable. Based on functional analysis, we demonstrated that the differentially expressed proteins were mainly involved in signal transduction which was implicated in cellular behavior. Collectively, our findings suggest that, for neurogenesis, GDF11 might not be the desired rejuvenation factor, but a potential target for pharmacological blockade.