Reduced Protein Activity Research Articles

STUDY OF NUTRIENT VALUE IN POST HARVESTED INFECTED ORANGE (CITRUS SINENSIS) FRUIT

Orange (Citrus sinensis) is a very nutrient and beneficial fruit all over the world. Study wereconducted on changes in the nutrient value like reducing sugar, non reducing sugar, starch, protein,phenol, vitamin C, alpha-amylase and total antioxidant activity of the post harvested infected orangefruit. In this analysis two fungi were isolated from infected orange fruits. The effect of these fungiindicate the reduction in non-reducing sugar, vitamin C, alpha-amylase and antioxidant activity butthe amount of reducing sugar, protein and phenol increased in infected fruit. The nutrient valuedeclined or increased due to the infection of penicillium and phytophthora fungus. From the presentinvestigation it can be concluded that the fungus decrease or increase the nutrient value of fruitbecause they use them for their successful growth and establishment.

Self-Immolative Hydroxybenzylamine Linkers for Traceless Protein Modification

Traceless self-immolative linkers are widely used for the reversible modification of proteins and peptides. This article describes a new class of traceless linkers based on ortho- or para-hydroxybenzylamines. The introduction of electron-donating substituents on the aromatic core stabilizes the quinone methide intermediate, thus providing a platform for payload release that can be modulated. To determine the extent to which the electronics affect the rate of release, we prepared a small library of hydroxybenzylamine linkers with varied electronics in the aromatic core, resulting in half-lives ranging from 20 to 144 h. Optimization of the linker design was carried out with mechanistic insights from density functional theory (DFT) and the in silico design of an intramolecular trapping agent through the use of DFT and intramolecular distortion energy calculations. This resulted in the development of a faster self-immolative linker with a half-life of 4.6 h. To demonstrate their effectiveness as traceless linkers for bioconjugation, reversible protein-polyethylene glycol conjugates with a model protein lysozyme were prepared, which had reduced protein activity but recovered ≥94% activity upon traceless release of the polymer. This new class of linkers with tunable release rates expands the traceless linkers toolbox for a variety of bioconjugation applications.

Elucidating clinical phenotypic variability associated with the polyT tract and TG repeats in CFTR.

Biallelic pathogenic variants in CFTR manifest as cystic fibrosis (CF) or other CFTR‐related disorders (CFTR‐RDs). The 5T allele, causing alternative splicing and reduced protein activity, is modulated by the adjacent TG repeat element, though previous data have been limited to small, selective cohorts. Here, the risk and spectrum of phenotypes associated with the CFTR TG‐T5 haplotype variants (TG11T5, TG12T5, and TG13T5) in the absence of the p.Arg117His variant are evaluated. Individuals who received physician‐ordered next‐generation sequencing of CFTR were included. TG[11‐13]T5 variant frequencies (biallelic or with another CF‐causing variant [CFvar]) were calculated. Clinical information reported by the ordering provider or the individual was examined. Among 548,300 individuals, the T5 minor allele frequency (MAF) was 4.2% (TG repeat distribution: TG11 = 68.1%, TG12 = 29.5%, TG13 = 2.4%). When present with a CFvar, each TG[11‐13]T5 variant was significantly enriched in individuals with a high suspicion of CF or CFTR‐RD (personal/family history of CF/CFTR‐RD) compared to those with a low suspicion for CF or CFTR‐RD (hereditary cancer screening, CFTR not requisitioned). Compared to CFvar/CFvar individuals, those with TG[11‐13]T5/CFvar generally had single‐organ involvement, milder symptoms, variable expressivity, and reduced penetrance. These data improve our understanding of disease risks associated with TG[11‐13]T5 variants and have important implications for reproductive genetic counseling.

Comparative evaluation of reagents for measuring protein S activity: possibility of harmonization.

Patients with congenital protein S (PS) deficiency show a hereditary predisposition for thrombosis, and PS deficiency is prevalent among Japanese populations. Diagnosis is based on symptoms of thrombosis and reduced PS activity. Three reagents that use different measurement principles for determining PS activity are available in Japan. This study aimed to confirm the possibility of harmonization of these three reagents to establish a universal standard for PS activity in Japanese populations. Commercial normal plasma and plasma samples obtained from healthy individuals and healthy pregnant women were tested at three facilities using three reagents for measuring PS: STA-Staclot Protein S (STA-PS), HemosIL Protein S (Clotting) (IL-PS), and a total PS assay (SNT-PS). The within-run precision of each reagent was good, as each had a coefficient of variation of ≤ 3.8%. The dilution linearity for each reagent was also good. The correlation coefficient was 0.94 for STA-PS vs. IL-PS, 0.93 for SNT-PS vs. STA-PS, and 0.90 for SNT-PS vs. IL-PS, indicating a good correlation. Although the three reagents available in Japan for measuring PS activity use different measurement methods, each showed good performance, and large differences were not observed between the obtained values. Harmonization among them appears possible.

Enhanced Binding and Reduced Immunogenicity of Glycoconjugates Prepared via Solid-State Photoactivation of Aliphatic Diazirine Carbohydrates.

Biological conjugation is an important tool employed for many basic research and clinical applications. While useful, common methods of biological conjugation suffer from a variety of limitations, such as (a) requiring the presence of specific surface-exposed residues, such as lysines or cysteines, (b) reducing protein activity, and/or (c) reducing protein stability and solubility. Use of photoreactive moieties including diazirines, azides, and benzophenones provide an alternative, mild approach to conjugation. Upon irradiation with UV and visible light, these functionalities generate highly reactive carbenes, nitrenes, and radical intermediates. Many of these will couple to proteins in a non-amino-acid-specific manner. The main hurdle for photoactivated biological conjugation is very low yield. In this study, we developed a solid-state method to increase conjugation efficiency of diazirine-containing carbohydrates to proteins. Using this methodology, we produced multivalent carbohydrate-protein conjugates with unaltered protein charge and secondary structure. Compared to carbohydrate conjugates prepared with amide linkages to lysine residues using standard NHS conjugation, the photoreactive prepared conjugates displayed up to 100-fold improved binding to lectins and diminished immunogenicity in mice. These results indicate that photoreactive bioconjugation could be especially useful for in vivo applications, such as lectin targeting, where high binding affinity and low immunogenicity are desired.

Acute Kidney Damage in Pregnancy: Etiopathogenesis, Diagnostics and Basic Principles of Treatment

Abstract Acute kidney damage associated with pregnancy occurs in 1/20.000 pregnancies. In developing countries, the main cause of the development of acute kidney damage is septic abortion, and preeclampsia in the developed countries of the world. Preeclampsia is defined as newly developed hypertension, proteinuria and swelling in pregnant women after the 20th week of gestation. It occurs due to disorders in the development of placenta and systemic disorders of the function of the endothelium of the mother. It is treated with methyldopa, magnesium sulfate and timely delivery. Urgent delivery is indicated if the age of gestation is ≥ 34 weeks. HELLP syndrome is a difficult form of preeclampsia. Its main characteristics are decreased platelet count, microangiopathic hemolysis anemia, increased concentration of aminotransferase in the serum and acute kidney damage. Severe HELLP syndrome is treated with emergency delivery, antihypertensives, magnesium sulfate, and in some cases plasmapheresis and hemodialysis. Acute fatty liver in pregnancy occurs because of decreased activity of the LCHAD enzyme of the fetus. Due to the reduced beta oxidation of fatty acids in the hepatocytes of the fetus, long chain fatty acids that cause damage to the mother’s hepatocytes are released. Swansea criteria are used for diagnosis, and the difficult form of the disease is treated with plasmapheresis and extracorporeal liver support. Atypical HUS is due to a reduced protein activity that regulates the activity of the alternative pathway of the complement system. Its main features are thrombocytopenia, microangiopathic hemolytic anemia and acute kidney damage. It is treated with plasmapheresis, and in case of resistance with eculizumab. Thrombotic thrombocytopenic purpura is due to decreased activity of the ADAMTS13 enzyme. It is characterized by thrombocytopenia, microangiopathic hemolytic anemia, high temperature, nervous system disorders and acute kidney damage. It is treated with plasmapheresis, and severe form of disease with corticosteroids and azathioprine. Early detection and timely treatment of acute kidney damage provides a good outcome for the mother and fetus.

Bioinformatics Analysis to Construct Cellulose-binding Module Synthetic Gene and Design Primer

Cellulose-binding module (CBM) is a protein domain commonly found in various types of cellulase enzymes. The function of this CBM can be used for the binding process and the immobilization of a protein in the cellulose matrix. CBM can be obtained from several organisms, one of them is Trichoderma reesei. To get a gene, it does not have to be isolated from the original organism. Gene sequences can be obtained synthetically through bioinformatics analysis in accordance with the same gene sequences as those at Gene Bank. Bioinformatics analysis can be used to find new gene sequences or existing genes. This study aims to get a cbmsyn synthetic gene quickly and efficiently without reducing protein activity, which can then be ligated with other genes so that it functions as an immobilized enzyme. From the results of bioinformatics analysis, obtained DNA sequences measuring around 498 pb with 166 amino acid protein lengths. The sequence was modified by adding several restriction sites, namely BamHI, AfeI, and ScaI. The DNA sequences obtained were optimized with the Pichia pastoris codon.

Covalently Linking Oligomerization-Impaired GlpF Protomers Does Not Completely Re-establish Wild-Type Channel Activity.

Integral membrane proteins of the aquaporin family facilitate rapid water flux across cellular membranes in all domains of life. Although the water-conducting pore is clearly defined in an aquaporin monomer, all aquaporins assemble into stable tetramers. In order to investigate the role of protomer–protomer interactions, we analyzed the activity of heterotetramers containing increasing fractions of mutated monomers, which have an impaired oligomerization propensity and activity. In order to enforce interaction between the protomers, we designed and analyzed a genetically fused homotetramer of GlpF, the aquaglyceroporin of the bacterium Escherichia coli (E. coli). However, increasing fractions of the oligomerization-impaired mutant GlpF E43A affected the activity of the GlpF heterotetramer in a nearly linear manner, indicating that the reduced protein activity, caused by the introduced mutations, cannot be fully compensated by simply covalently linking the monomers. Taken together, the results underline the importance of exactly positioned monomer–monomer contacts in an assembled GlpF tetramer.

Resistance of Leishmania infantum to allopurinol is associated with chromosome and gene copy number variations including decrease in the S-adenosylmethionine synthetase (METK) gene copy number

Leishmania infantum is one of the causative agents of visceral leishmaniasis (VL), a widespread, life-threatening disease. This parasite is responsible for the majority of human VL cases in Brazil, the Middle East, China, Central Asia and the Mediterranean basin. Its main reservoir are domestic dogs which, similar to human patients, may develop severe visceral disease and die if not treated. The drug allopurinol is used for the long-term maintenance of dogs with canine leishmaniasis. Following our report of allopurinol resistance in treated relapsed dogs, we investigated the mechanisms and markers of resistance to this drug. Whole genome sequencing (WGS) of clinical resistant and susceptible strains, and laboratory induced resistant parasites, was carried out in order to detect genetic changes associated with resistance. Significant gene copy number variation (CNV) was found between resistant and susceptible isolates at several loci, including a locus on chromosome 30 containing the genes LinJ.30.3550 through LinJ.30.3580. A reduction in copy number for LinJ.30.3560, encoding the S-adenosylmethionine synthetase (METK) gene, was found in two resistant clinical isolates and four induced resistant clonal strains. Using quantitative real time PCR, this reduction in METK copy number was also found in three additional resistant clinical isolates. Furthermore, inhibition of S-adenosylmethionine synthetase encoded by the METK gene in allopurinol susceptible strains resulted in increased allopurinol resistance, confirming its role in resistance to allopurinol. In conclusion, this study identified genetic changes associated with L. infantum resistance to allopurinol and the reduction in METK copy number identified may serve as a marker for resistance in dogs, and reduced protein activity correlated with increased allopurinol resistance.

OsPK2 encodes a plastidic pyruvate kinase involved in rice endosperm starch synthesis, compound granule formation and grain filling.

SummaryStarch is the main form of energy storage in higher plants. Although several enzymes and regulators of starch biosynthesis have been defined, the complete molecular machinery remains largely unknown. Screening for irregularities in endosperm formation in rice represents valuable prospect for studying starch synthesis pathway. Here, we identified a novel rice white‐core endosperm and defective grain filling mutant, ospk2, which displays significantly lower grain weight, decreased starch content and alteration of starch physicochemical properties when compared to wild‐type grains. The normal starch compound granules were drastically reduced and more single granules filled the endosperm cells of ospk2. Meanwhile, the germination rate of ospk2 seeds after 1‐year storage was observably reduced compared with wild‐type. Map‐based cloning of OsPK2 indicated that it encodes a pyruvate kinase (PK, ATP: pyruvate 2‐O‐phosphotransferase, EC 2.7.1.40), which catalyses an irreversible step of glycolysis. OsPK2 has a constitutive expression in rice and its protein localizes in chloroplasts. Enzyme assay showed that the protein product from expressed OsPK2 and the crude protein extracted from tissues of wild‐type exhibits strong PK activity; however, the mutant presented reduced protein activity. OsPK2 (PKpα1) and three other putative rice plastidic isozymes, PKpα2, PKpβ1 and PKpβ2, can interact to form heteromer. Moreover, the mutation leads to multiple metabolic disorders. Altogether, these results denote new insights into the role of OsPK2 in plant seed development, especially in starch synthesis, compound granules formation and grain filling, which would be useful for genetic improvement of high yield and rice grain quality.

Characterization of a New Staphylococcus aureus Kayvirus Harboring a Lysin Active against Biofilms.

Staphylococcus aureus is one of the most relevant opportunistic pathogens involved in many biofilm-associated diseases, and is a major cause of nosocomial infections, mainly due to the increasing prevalence of multidrug-resistant strains. Consequently, alternative methods to eradicate the pathogen are urgent. It has been previously shown that polyvalent staphylococcal kayviruses and their derived endolysins are excellent candidates for therapy. Here we present the characterization of a new bacteriophage: vB_SauM-LM12 (LM12). LM12 has a broad host range (>90%; 56 strains tested), and is active against several MRSA strains. The genome of LM12 is composed of a dsDNA molecule with 143,625 bp, with average GC content of 30.25% and codes for 227 Coding Sequences (CDSs). Bioinformatics analysis did not identify any gene encoding virulence factors, toxins, or antibiotic resistance determinants. Antibiofilm assays have shown that this phage significantly reduced the number of viable cells (less than one order of magnitude). Moreover, the encoded endolysin also showed activity against biofilms, with a consistent biomass reduction during prolonged periods of treatment (of about one order of magnitude). Interestingly, the endolysin was shown to be much more active against stationary-phase cells and suspended biofilm cells than against intact and scraped biofilms, suggesting that cellular aggregates protected by the biofilm matrix reduced protein activity. Both phage LM12 and its endolysin seem to have a strong antimicrobial effect and broad host range against S. aureus, suggesting their potential to treat S. aureus biofilm infections.

Comparison of melibiose and trehalose as stabilising excipients for spray-dried β-galactosidase formulations

Spray-dried protein formulations commonly require stabilising excipients to prevent protein degradation during processing and storage, and trehalose has been commonly used. The purpose of this work was to evaluate melibiose in spray-dried protein formulations in comparison to trehalose. The protein-activity-preserving efficacy, process behaviour and storage stability were studied. Spray drying of β-galactosidase was carried out using different process temperature, drying air flow and feed liquid atomisation settings. Both melibiose and trehalose reduced protein activity loss during drying. A decrease in activities was observed when the process temperature exceeded a threshold temperature. During storage (30 days at 18% RH and 20 or 40 °C), the formulations dried below this threshold temperature showed no further activity loss, and the stabilising efficacy of the two disaccharides was equal. With higher process temperatures, the remaining protein activities after storage trended higher with melibiose formulations. All formulations remained amorphous. The powder yields of melibiose formulations were similar to trehalose. There was a difference in residual moisture contents, with melibiose formulations giving drier products. In conclusion, protein formulations with melibiose could be spray dried into amorphous powders that were physically stable, contained lower moisture contents and protected protein activity at least as well as trehalose formulations.

Chimeric proteins tagged with specific 3xHA cassettes may present instability and functional problems.

Epitope-tagging of proteins has become a widespread technique for the analysis of protein function, protein interactions and protein localization among others. Tagging of genes by chromosomal integration of PCR amplified cassettes is a widely used and fast method to label proteins in vivo. Different systems have been developed during years in the yeast Saccharomyces cerevisiae. In the present study, we analysed systematically a set of yeast proteins that were fused to different tags. Analysis of the tagged proteins revealed an unexpected general effect on protein level when some specific tagging module was used. This was due in all cases to a destabilization of the proteins and caused a reduced protein activity in the cell that was only apparent in particular conditions. Therefore, an extremely cautious approach is required when using this strategy.

Decreased TRPM7 inhibits activities and induces apoptosis of bladder cancer cells via ERK1/2 pathway.

Transient receptor potential melastatin 7 (TRPM7) functions as a Mg2+/Ca2+-permeable channel fused with a kinase domain and regulates various physical processes and diseases. However, its effects on pathogenesis of human bladder cancer (BCa) has not been clarified yet. Our microarray analysis has suggested that calcium signaling pathway is connected with bladder cancer via MAPK pathway. Therefore, we aim to investigate the mechanism of TRPM7 in BCa tumorigenesis by using BCa tissues compared with normal bladder epithelium tissues, as well as using distinct BCa cell lines (EJ, 5637 and T24). We observed increased TRPM7 expression and dysregulation of proteins involved in Epithelial-Mesenchymal Transition (EMT) in BCa tissues. Moreover, knockdown of TRPM7 in BCa cells reversed the EMT status, accompanied by increase of reactive oxygen species (ROS). Furthermore, TRPM7 deficiency could inhibit BCa cell proliferation, migration and invasion, as well as induce p-ERK1/2 and suppress PI3K/AKT at the protein level. Downregulation of TRPM7 promoted cell cycle arrest at G0/G1 phase and apoptosis in vitro, which could be recovered by pre-treatment with U0126 to deactivate ERK1/2, suggesting a close correlation between TRPM7 and the MAPK signaling pathway. Furthermore, a NOD/SCID mouse model transplanted using the BCa cells was established, revealing delayed tumor growth by reduced protein activity and mRNA transcription of TRPM7 in vivo. Our results suggested TRPM7 might be essential for BCa tumorigenesis by interfering BCa cell proliferation, motility and apoptosis.

Low-Temperature Processable Block Copolymers That Preserve the Function of Blended Proteins.

Low-temperature processable polymers have attracted increasing interest as ecological materials because of their reduced energy consumption during processing and suitability for making composites with heat-sensitive biomolecules at ambient temperature. In the current study, low-temperature processable biodegradable block copolymers were synthesized by ring-opening polymerization of l-lactide (LLA) using polyphosphoester as a macroinitiator. The polymer films could be processed under a hydraulic pressure of 35 MPa. The block copolymer films swelled in water because the polyphosphoester block was partially hydrated. Interestingly, the swelling ratio of the films changed with temperature. The pressure-induced order-to-disorder transition of the block copolymers was characterized by small-angle X-ray scattering; a crystallinity reduction in the block copolymers was observed after application of pressure. The crystallinity of the block copolymers was recovered after removing the applied pressure. The Young's modulus of the block copolymer films increased as the LLA unit content increased. Moreover, the modulus did not change after multiple processing cycles and the recyclability of the block copolymers was also confirmed. Finally, polymer films with embedded proteinase K as a model protein were prepared. The activity of catalase loaded into the polymer films was evaluated after processing at different temperatures. The activity of catalase was preserved when the polymer films were processed at room temperature but was significantly reduced after high-temperature processing. The suitability of low-temperature processable biodegradable polymers for making biofunctional composites without reducing protein activity was clarified. These materials will be useful for biomedical and therapeutic applications.

ChemInform Abstract: Site‐Specific PEGylation of Proteins: Recent Developments

AbstractReview: 69 refs.

BRF1 mutations alter RNA polymerase III-dependent transcription and cause neurodevelopmental anomalies.

RNA polymerase III (Pol III) synthesizes tRNAs and other small noncoding RNAs to regulate protein synthesis. Dysregulation of Pol III transcription has been linked to cancer, and germline mutations in genes encoding Pol III subunits or tRNA processing factors cause neurogenetic disorders in humans, such as hypomyelinating leukodystrophies and pontocerebellar hypoplasia. Here we describe an autosomal recessive disorder characterized by cerebellar hypoplasia and intellectual disability, as well as facial dysmorphic features, short stature, microcephaly, and dental anomalies. Whole-exome sequencing revealed biallelic missense alterations of BRF1 in three families. In support of the pathogenic potential of the discovered alleles, suppression or CRISPR-mediated deletion of brf1 in zebrafish embryos recapitulated key neurodevelopmental phenotypes; in vivo complementation showed all four candidate mutations to be pathogenic in an apparent isoform-specific context. BRF1 associates with BDP1 and TBP to form the transcription factor IIIB (TFIIIB), which recruits Pol III to target genes. We show that disease-causing mutations reduce Brf1 occupancy at tRNA target genes in Saccharomyces cerevisiae and impair cell growth. Moreover, BRF1 mutations reduce Pol III–related transcription activity in vitro. Taken together, our data show that BRF1 mutations that reduce protein activity cause neurodevelopmental anomalies, suggesting that BRF1-mediated Pol III transcription is required for normal cerebellar and cognitive development.

Site-specific PEGylation of Proteins: Recent Developments

The attachment of linear polyethylene glycol (PEG) to peptides and proteins for their stabilization for in vivo applications is a milestone in pharmaceutical research and protein-drug development. However, conventional methods often lead to heterogeneous PEGylation mixtures with reduced protein activity. Current synthetic efforts aim to provide site-specific approaches by chemoselective targeting of canonical and noncanonical amino acids and to improve the PEG architecture. This synopsis highlights recent work in this area, which also resulted in improved pharmacokinetics of peptide and protein therapeutics.

Molecular Analysis of Two Novel Missense Mutations in the GDF5 Proregion That Reduce Protein Activity and Are Associated with Brachydactyly Type C

Growth and differentiation factor 5 (GDF5) plays a central role in bone and cartilage development by regulating the proliferation and differentiation of chondrogenic tissue. GDF5 is synthesized as a preproprotein. The biological function of the proregion comprising 354 residues is undefined. We identified two families with a heterozygosity for the novel missense mutations p.T201P or p.L263P located in the proregion of GDF5. The patients presented with dominant brachydactyly type C characterized by the shortening of skeletal elements in the distal extremities. Both mutations gave rise to decreased biological activity in in vitro analyses. The variants reduced the GDF5-induced activation of SMAD signaling by the GDF5 receptors BMPR1A and BMPR1B. Ectopic expression in micromass cultures yielded relatively low protein levels of the variants and showed diminished chondrogenic activity as compared to wild-type GDF5. Interestingly, stimulation of micromass cells with recombinant human proGDF5T201P and proGDF5L263P revealed their reduced chondrogenic potential compared to the wild-type protein. Limited proteolysis of the mutant recombinant proproteins resulted in a fragment pattern profoundly different from wild-type proGDF5. Modeling of a part of the GDF5 proregion into the known three-dimensional structure of TGFβ1 latency-associated peptide revealed that the homologous positions of both mutations are conserved regions that may be important for the folding of the mature protein or the assembly of dimeric protein complexes. We hypothesize that the missense mutations p.T201P and p.L263P interfere with the protein structure and thereby reduce the amount of fully processed, biologically active GDF5, finally causing the clinical loss of function phenotype.

Lipegfilgrastim: A long-acting, once-per-cycle, glycopegylated recombinant human filgrastim.

e13548 Background: Lipegfilgrastim is a once-per-cycle fixed-dose glycoPEGylated granulocyte-colony stimulating factor (G-CSF) under development for the prevention of severe neutropenia in cancer patients receiving chemotherapy (CTx). PEGylation of a molecule extends its half-life in the body, requiring less frequent dosing and allowing for administration of G-CSF once per CTx cycle, making treatment potentially less expensive and enhancing patient compliance and safety. Briefly, traditional PEGylation methods use chemical conjugation through reactive groups on amino acids, which may reduce protein activity and result in non-uniform chemical and pharmaceutical properties. Here, we describe a highly site-specific GlycoPEGylation technology for site-directed PEGylation and summarize preclinical findings compared with pegfilgrastim (Neulasta). Methods: Glycosylation sequon scanning was used to identify the glycoPEGylation site with least impact on protein activity. E. coli-expressed G-CSF was selectively glycosylated at natural O-glycosylation sites and a polyethylene glycol (PEG) sialic acid derivative attached using a sialyltransferase (glycoPEGylation technology). Ligand binding affinity was assessed using the BIACORE 3000 system. Biologic activity of lipegfilgrastim was assessed in an NFS-60 cell line proliferation assay vs filgrastim and pegfilgrastim. PK and PD properties were studied in healthy and neutropenic animal models. Results: GlycoPEGylation produces long-acting G-CSF with improved PK profiles. In vitro, lipegfilgrastim had binding affinity and specific activity comparable to pegfilgrastim, and both were lower than non-PEGylated filgrastim. Comparable increases in leukocytes, neutrophilic granulocytes, and monocytes were seen with lipegfilgrastim and pegfilgrastim in rats and monkeys and were consistent with the effects expected for a long-lasting G-CSF. Conclusions: GlycoPEGylation technology platform is used to produce lipegfilgrastim – a novel, biologically active G-CSF with greater structural homogeneity and comparable pharmacologic properties to conventionally PEGylated G-CSFs.