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Alpha1-antitrypsin is a kind of plasma protein that requires a sequence of different fractionation steps to get generally. To report an effective process for isolating and purifying alpha1-antitrypsin from Cohn Fraction IV based upon a new immunoaffinity chromatography medium, named “Alpha-1 Antitrypsin Select,” characterization of alpha1-antitrypsin (α1-AT) was performed by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), Western blot, and tandem mass spectroscopy. Total protein content was determined by the method of Bradford under visible light absorption at 595 nm. Pretreatment process and the immunoaffinity chromatography step achieved a 60.35 ± 1.39% yield. Thus, an overall 71.68 ± 1.32 fold increase in purity and a 41.88 ± 6.98% yield were obtained from plasma. The α1-AT had a specific activity of about 1.00–1.05 PU/mg. This technique will develop an effective process for isolating and purifying, with high purity and specific activity, alpha1-antitrypsin from Cohn Fraction IV or human whole plasma, which could be an efficient and scaled-up method for alpha1-antitrypsin products purification. [ABSTRACT FROM AUTHOR]

In order to increase the yield of prothrombin complex concentrates (PCCs) and to reduce their associated thrombotic risks, the influence of washing conditions on the yield, purity, and balance of coagulation factors (FII, FVII, FIX, and FX), and inhibitor proteins (PC, PS, PZ, and AT [antithrombin]) in PCCs was investigated by orthogonal testing, in which three variables (sodium citrate, NaCl, and pH) and their three levels were selected. It was found that AT yield and purity were extraordinarily low, and at lower NaCl content, the general yield, purity, and balance were higher, lower, and better, respectively; however, the results became contrary at higher NaCl. Moreover, within the investigated levels, NaCl was the first determinant for the yield except AT and the purity except FVII, PC, PS, and AT. Sodium citrate was the first determinant for AT yield and FVII, PS, and AT purity. The yield except FII, PS, and AT decreased and the purity except PC increased with increase of sodium citrate content. Just for PC purity, pH was the first determinant. The effect with pH fluctuation on the yield and purity was characteristically unobvious. The outcome undoubtedly supplies the guidance to further improve PCCs. [ABSTRACT FROM PUBLISHER]

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. [ABSTRACT FROM AUTHOR]

Background: The variations in sequence, three-dimensional structure, and post-translational modifications (PTMs) of human serum albumin (HSA) are crucial for its physiological functions. This study aims to analyze and compare the disparities in PTMs between HSA derived from human plasma and genetically recombinant sources for clinical treatments in China., Methods: Six distinct PTMs, namely acetylation, succinylation, crotonylation, phosphorylation, beta-hydroxybutyrylation, and lactylation, were identified using pan-specific antibodies via Western blot analysis. The samples, comprising human plasma-derived HSA (pHSA) from six different manufacturers and recombinant HSA (rHSA) expressed in yeast and Oryza sativa , underwent detection for various types of PTMs. Additionally, a 4D label-free quantitative proteomic analysis was performed to identify N-glycosylation and the aforementioned PTMs in both pHSA and rHSA samples. This analysis aimed to discern disparities in modification sites and levels., Results: Through Western blot analysis, all six pHSA and two rHSA samples displayed positive bands for albumin (66.5 kDa) across the six PTMs. Subsequent analysis using 4D label-free quantitative proteomics revealed 25 (29) acetylated, 30 (32) succinylated, 41 (50) malonylated, 15 (23) phosphorylated, 36 (30) beta-hydroxybutyrylated, and 27 (34) lactylated modification sites in pHSA and rHSA samples, with no N-glycosylation modification sites detected. The analysis identified 1 acetylation (ALB_K160), 2 beta-hydroxybutyrylation (ALB_K569, ALB_K426), and 3 crotonylation (ALB_K264, ALB_K581, ALB_K560) specific modification sites in pHSA, as well as 3 crotonylation (ALB_K560, ALB_K562, ALB_K75), 1 succinylation (ALB_K490), and 23 phosphorylation specific modification sites in rHSA. In pHSA (rHSA), 2 (6) acetylation, 10 (12) succinylation, 0 (9) crotonylation, 1 (9) phosphorylation, 6 (0) beta-hydroxybutyrylation, and 0 (7) lactylation specific modification sites were found. Moreover, in the shared modification sites between pHSA and rHSA, pHSA exhibited up-regulation of amberylation (16:1) and beta-hydroxybutyrylation (12:2) in more sites, and up-regulation of acetylation (7:11), crotonylation (2:11), phosphorylation (1:8), and lactylation (1:14) in fewer sites compared to rHSA., Conclusion: In clinical practice, both pHSA and rHSA utilized in China commonly display acetylation, succinylation, crotonylation, phosphorylation, beta-hydroxybutyrylation, and lactylation. Notably, there exist distinctions in the site characteristics and modification levels of these alterations between pHSA and rHSA. Further experimental inquiries are imperative to delve into the implications of these disparities in PTMs on the biological functionality, effectiveness, and safety of pHSA and rHSA.

Background: As the most basic material, synthetic human Amyloid-β (1-42) (Aβ 42 ) peptide from different manufacturers have been widely used. Their aggregation ability is vital to the reliability, repeatability and comparability of studies on Aβ 42 physiology and pathology. However, it has not been evaluated and compared., Objective: To analyze the consistency of the aggregation ability of 5 commercially available Aβ 42 peptide., Methods: 5 Aβ 42 peptide represented as A, B, C, D and E were pretreated by HFIP. The pretreated Aβ 42 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 Aβ 42 peptide showed obvious differences in aggregation ability, which should arouse enough attention in the field of basic study related to Aβ 42 . 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., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

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., (© 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Alpha1-antitrypsin is a kind of plasma protein that requires a sequence of different fractionation steps to get generally. To report an effective process for isolating and purifying alpha1-antitrypsin from Cohn Fraction IV based upon a new immunoaffinity chromatography medium, named "Alpha-1 Antitrypsin Select," characterization of alpha1-antitrypsin (α1-AT) was performed by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), Western blot, and tandem mass spectroscopy. Total protein content was determined by the method of Bradford under visible light absorption at 595 nm. Pretreatment process and the immunoaffinity chromatography step achieved a 60.35 ± 1.39% yield. Thus, an overall 71.68 ± 1.32 fold increase in purity and a 41.88 ± 6.98% yield were obtained from plasma. The α1-AT had a specific activity of about 1.00-1.05 PU/mg. This technique will develop an effective process for isolating and purifying, with high purity and specific activity, alpha1-antitrypsin from Cohn Fraction IV or human whole plasma, which could be an efficient and scaled-up method for alpha1-antitrypsin products purification.