Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 829
Filter
1.
PLoS One ; 17(10): e0276775, 2022.
Article in English | MEDLINE | ID: mdl-36301906

ABSTRACT

Plasma fibrinogen and albumin concentrations initially decrease after abdominal surgery. On postoperative days 3-5 fibrinogen concentration returns to the preoperative level or even higher, while albumin stays low. It is not known if these altered plasma concentrations reflect changes in synthesis rate, utilization, or both. In particular a low albumin plasma concentration has often been attributed to a low synthesis rate, which is not always the case. The objective of this study was to determine fibrinogen and albumin quantitative synthesis rates in patients undergoing major upper abdominal surgery with and without intact liver size. Patients undergoing liver or pancreatic resection (n = 9+6) were studied preoperatively, on postoperative days 1 and 3-5. De novo synthesis of fibrinogen and albumin was determined; in addition, several biomarkers indicative of fibrinogen utilization were monitored. After hemihepatectomy, fibrinogen synthesis was 2-3-fold higher on postoperative day 1 than preoperatively. On postoperative days 3-5 the synthesis level was still higher than preoperatively. Following major liver resections albumin synthesis was not altered postoperatively compared to preoperative values. After pancreatic resection, on postoperative day 1 fibrinogen synthesis was 5-6-fold higher than preoperatively and albumin synthesis 1.5-fold higher. On postoperative days 3-5, synthesis levels returned to preoperative levels. Despite decreases in plasma concentrations, de novo synthesis of fibrinogen was markedly stimulated on postoperative day 1 after both hemihepatectomies and pancreatectomies, while de novo albumin synthesis remained grossly unchanged. The less pronounced changes seen following hepatectomies were possibly related to the loss of liver tissue.


Subject(s)
Digestive System Surgical Procedures , Fibrinogen , Hemostatics , Serum Albumin , Humans , Abdomen/surgery , Fibrinogen/biosynthesis , Hepatectomy , Liver/surgery , Serum Albumin/biosynthesis
2.
Eur J Haematol ; 107(1): 48-53, 2021 Jul.
Article in English | MEDLINE | ID: mdl-33655560

ABSTRACT

INTRODUCTION: Hypoalbuminemia is a known adverse prognostic factor in lymphomas. Yet, it is unknown if axicabtagene ciloleucel (axi-cel) overcomes the adverse prognostic impact of hypoalbuminemia in relapsed/refractory large B-cell lymphoma. METHODS: We conducted a retrospective analysis across three Mayo Clinic centers to assess the relationship of hypoalbuminemia (defined as a serum albumin (SA) levels ≤ 3.5 g/dL) on outcomes of patients treated with axi-cel. RESULTS: This analysis included 81 patients. Two patients had no available SA levels preceding axi-cel infusion. Eighteen patients (22.8%) had hypoalbuminemia with a median SA of 3.3 g/dL. Patients with normal SA had a statistically higher ORR than those without hypoalbuminemia (P = .018). There was no difference in 1-year PFS and OS between the group with hypoalbuminemia and the group with normal SA levels (48% vs 49%, P = .81) and (74% vs 73%, P = .97), respectively. There was no difference in the severity or median duration of cytokine release syndrome or neurotoxicity between the two groups. CONCLUSION: Notwithstanding the limitations related to the relatively small sample size, axi-cel therapy appears to overcome the adverse effect of hypoalbuminemia on OS and PFS. Large multicenter clinical studies are certainly needed to validate these findings.


Subject(s)
Antigens, CD19/biosynthesis , Biological Products/therapeutic use , Cytokine Release Syndrome , Hypoalbuminemia/drug therapy , Lymphoma, Large B-Cell, Diffuse/drug therapy , Adult , Aged , Biological Products/adverse effects , Cytokines/metabolism , Female , Humans , Hypoalbuminemia/complications , Immunotherapy, Adoptive , Inflammation , Lymphoma, Large B-Cell, Diffuse/complications , Male , Middle Aged , Prognosis , Retrospective Studies , Serum Albumin/biosynthesis , Treatment Outcome
3.
Clin Neurol Neurosurg ; 201: 106428, 2021 02.
Article in English | MEDLINE | ID: mdl-33383467

ABSTRACT

BACKGROUND: We aimed to build a modified systemic inflammatory score(mSIS) based on preoperative albumin, fibrinogen, lactate dehydrogenase, and neutrophil-lymphocyte ratio in patients with high-grade glioma. MATERIAL AND METHODS: Data of 318 patients with high-grade gliomas were retrospectively analyzed. The SIS was developed and its associations with clinicopathological features and overall survival (OS) were evaluated. RESULTS: The mSIS consisted of serum albumin, fibrinogen, lactate dehydrogenase and neutrophil-lymphocyte ratio. A high mSIS was significantly associated with age(p < 0.001), sex(p = 0.048), lymphocyte-monocyte ratio (LMR)(p = 0.025), C-reactive protein(p < 0.001), tumor grade(p = 0.006) and served as an independent prognostic factor of reduced overall survival and progression-free survival (PFS). Subgroup analysis showed that the mSIS could significantly stratify patient prognosis in different tumor grades and adjuvant therapies. CONCLUSIONS: mSIS may predict survival and disease regression in high-grade glioma patients undergoing surgery. Management of HGG patients may need consideration of host inflammatory status.


Subject(s)
Brain Neoplasms/diagnosis , Brain Neoplasms/surgery , Glioma/diagnosis , Glioma/surgery , Adult , Humans , Inflammation/blood , Inflammation/diagnosis , Lymphocytes/pathology , Male , Middle Aged , Monocytes/pathology , Prognosis , Serum Albumin/biosynthesis
4.
Pharm Biol ; 58(1): 1252-1262, 2020 Dec.
Article in English | MEDLINE | ID: mdl-33332210

ABSTRACT

CONTEXT: Dexamethasone (DXM) has an anti-immunoinflammatory effect, and is often used in acute kidney injury (AKI). However, the effects of DXM on albumin (ALB) have not been fully studied. OBJECTIVE: To investigate the effects of DXM on ALB production and renal function. MATERIALS AND METHODS: Male Wistar rats were divided into normal and DXM groups (0.25, 0.5, 1 mg/kg for 5 days) (n = 15) for a dose-dependent study. Rats were divided into normal group and DXM groups (0.5 mg/kg for 3, 5, 7 days) (n = 9) for a time-dependent study. In AKI experiment, rats were divided into normal (saline), cisplatin (CP, 5 mg/kg, i.v.), CP + DXM groups (0.25, 0.5 and 1 mg/kg, i.m.) (n = 16). The blood and the organs were isolated for analysis. RESULTS: In normal, serum ALB (sALB) and serum total protein (sTP) increased in DXM group with sALB increased 19.8-32.2% (from small to large dosages); and 30.2-32.5.6% (from 3 to 7 days of DXM); sTP 15.7-22.6% and 14.2-24.3%; urine ALB (uALB) 31.5-392.3%, and 1047.2-1390.8%; urine TP (uTP) 0.68-173.1% and 98.0-504.9%, compared with normal groups. DXM increased the mRNA expression of Cebp and Hnf, suppressing podocin. In AKI, DXM decreased serum BUN (53.7%), serum Cre (73.4%), sALB (30.0%), sTP (18.7%), uALB (74.5%), uTP (449.3%), rescuing the suppressed podocin in kidney. CONCLUSIONS: DXM acts on Cebp and Hnf and promotes ALB production. This finding helps to evaluate the rationale of DXM for kidney injury.


Subject(s)
Acute Kidney Injury/metabolism , Dexamethasone/pharmacology , Serum Albumin/biosynthesis , Animals , Blood Proteins/analysis , Cisplatin/toxicity , Dose-Response Relationship, Drug , Enhancer Elements, Genetic/physiology , Kidney/drug effects , Male , Rats , Rats, Wistar
5.
Fetal Pediatr Pathol ; 38(6): 484-489, 2019 Dec.
Article in English | MEDLINE | ID: mdl-31232622

ABSTRACT

Aim: The aim is to compare the markers of oxidative stress in iron deficient children to that of non-anemic children. Method: Serum thiol-disulfide level, ferroxidase activity and ischemia-modified albumin (IMA) levels were compared between iron deficiency anemia (IDA) and non-anemic children. Results: A total of 117 children, 66 with IDA and 51 non-anemic children were included in the study. Disulfide, disulfide/native thiol, and disulfide/total thiol levels were significantly higher in the IDA group (p: 0.001). Serum ferroxidase levels were significantly lower in the IDA group (p: 0.04); but there was no significant difference between the two groups regarding serum IMA levels (p: 0.42). There was a weak negative correlation between disulfide and serum hemoglobin (p: 0.004), iron (p: 0.041), and ferritin (p: 0.023) levels while there was a weak positive correlation between ferroxidase activity and these parameters. Conclusion: There is an increased protein oxidation in children with IDA compared with non-anemic controls.


Subject(s)
Anemia, Iron-Deficiency/blood , Disulfides/blood , Homeostasis/physiology , Adolescent , Biomarkers/blood , Case-Control Studies , Ceruloplasmin , Child , Child, Preschool , Female , Humans , Infant , Male , Oxidative Stress/physiology , Serum Albumin/biosynthesis , Serum Albumin, Human , Sulfhydryl Compounds/blood
6.
Fetal Pediatr Pathol ; 38(2): 138-145, 2019 Apr.
Article in English | MEDLINE | ID: mdl-30741063

ABSTRACT

AIM: Hyperbilirubinemia causes oxidative stress. METHOD: We evaluated three oxidative stress markers in hyperbilirubinemic neonates (native/total thiol levels, serum ferroxidase activity and ischemia modified albumin (IMA), comparing these levels to levels in a control group to determine which indicators were the most sensitive. RESULTS: Serum from 124 term infants (67 with pathologic jaundice and 57 controls) were evaluated. Native/total thiol ratio was significantly lower (p:0.021) while disulfide levels were significantly higher (p:0.001) in the jaundiced group. There was no significant difference in ferroxidase (p:0.603) or IMA (p:0.251) levels. CONCLUSION: Altered thiol/disulfide homeostasis in the favor of disulfide indicates augmented oxidative stress in jaundiced term infants. The lack of alteration in ferroxidase or IMA levels suggests these latter alterations take more time or more severe oxidative stress to become altered or are not as sensitive as the thiol/disulfide ratio to detect oxidative stress states.


Subject(s)
Biomarkers/blood , Disulfides/blood , Homeostasis/physiology , Ceruloplasmin/biosynthesis , Humans , Infant , Infant, Newborn , Jaundice, Neonatal/blood , Oxidative Stress/physiology , Serum Albumin/biosynthesis , Serum Albumin, Human , Sulfhydryl Compounds/blood
7.
Amino Acids ; 50(12): 1719-1727, 2018 Dec.
Article in English | MEDLINE | ID: mdl-30178102

ABSTRACT

Traditionally, the effect of dietary lysine upon health is determined through the concentrations of plasma proteins, but sometimes they are not responsive to lysine intake. We hypothesized that the fractional synthesis rates (FSRs) of plasma proteins may be more sensitive to dietary intake of lysine than protein concentrations in plasma. Seventy-two male Sprague-Dawley rats were divided randomly into three groups based on their diets provided for 18 weeks: low lysine (LG), normal lysine (NG) and high lysine (HG). Rats underwent labeling with deuterated water, a more reliable tracer than amino-acid tracers. The FSRs of albumin and immunoglobulin (Ig) G in plasma increased with increasing dietary intake of lysine. However, the albumin concentration in plasma in rats in the LG did not decrease significantly compared with that in the NG, and a similar result was shown for the IgG concentration between the NG and HG. These results suggested that the FSRs of albumin and IgG in plasma were more sensitive to dietary intake of lysine than their concentrations, and could be useful as sensitive indicators of the effect of dietary lysine upon health.


Subject(s)
Diet , Immunoglobulin G/biosynthesis , Lysine/administration & dosage , Serum Albumin/biosynthesis , Animals , Deuterium Oxide , Rats , Rats, Sprague-Dawley
8.
Nutrients ; 10(6)2018 Jun 12.
Article in English | MEDLINE | ID: mdl-29895783

ABSTRACT

Chicken serum albumin (CSA) is a hen's egg yolk allergen causing IgE-mediated allergy. The objective of this study was to produce a recombinant version of CSA and compare its IgE reactivity to natural CSA (nCSA). CSA was cloned and expressed as a soluble fraction in the yeast Kluyveromyces lactis (K. lactis) protein expression system. The gene encoding CSA was amplified with a C-terminal hemagglutinin epitope tag by polymerase chain reaction (PCR) and cloned into the pKLAC2 expression vector prior to transforming into K. lactis. Recombinant CSA (rCSA) was purified by immunoprecipitation. Twenty-one patients allergic to hen's egg white were examined for sensitisation against nCSA. 38% of patients were found to be sensitised to CSA based on Western immunoassay. Immunoglobulin E (IgE) binding capacity of rCSA and nCSA was analysed by ELISA using sera from patients sensitised to CSA. Levels of IgE-binding were similar for both the recombinant and the natural CSA, indicating the existence of similar epitopes. rCSA produced in this study is a potential candidate to be used in component-resolved diagnosis (CRD) of egg yolk allergy. The usefulness of rCSA in CRD of egg yolk allergy warrants further characterisation using sera from patients with allergy to hen's egg yolk in future studies.


Subject(s)
Allergens/immunology , Chickens/immunology , Egg Hypersensitivity/immunology , Egg Proteins, Dietary/immunology , Immunoglobulin E/blood , Kluyveromyces/immunology , Serum Albumin/immunology , Allergens/biosynthesis , Allergens/genetics , Animals , Antibody Specificity , Biomarkers/blood , Chickens/genetics , Chickens/metabolism , Egg Hypersensitivity/blood , Egg Hypersensitivity/diagnosis , Egg Proteins, Dietary/metabolism , Epitopes , Humans , Kluyveromyces/genetics , Kluyveromyces/metabolism , Recombinant Proteins/immunology , Serum Albumin/biosynthesis , Serum Albumin/genetics
9.
Xenotransplantation ; 25(2): e12384, 2018 03.
Article in English | MEDLINE | ID: mdl-29359356

ABSTRACT

BACKGROUND: The development of a precise and easy-to-use tool for monitoring islet graft function is important in clarifying the causes of graft loss, identifying appropriate therapy, and ensuring graft survival in the nonhuman primate (NHP) model of porcine islet transplantation (PITx). Glycated albumin (GA) is an indicator of intermediate-term changes in blood glucose control and is useful in clinical diabetes management. The validity of GA for monitoring graft function in NHP recipients of PITx was evaluated using a retrospective analysis of cohort samples. METHODS: Data from a total of 23 PITxs performed in 20 recipients (3 were retransplanted) were included in this study. Islet clusters purified from adult wild-type pigs were transplanted via the intraportal route into streptozotocin-induced diabetic rhesus monkeys with immune suppression. Blood samples were obtained once per week from the recipients until they lost insulin-independence. Blood samples were also obtained from 69 non-diabetic monkeys that served as a control group. The levels of GA and albumin in stored plasma aliquots were measured using each enzymatic method, and the GA result was expressed as the percentage of GA level to the total albumin level. RESULTS: The median level of GA in the recipients on the day of PITx (median 18.6%, 95% confidence interval [CI] 16.7%-20.4%) was significantly higher than that of healthy controls (median 9.14%, 95% CI 9.0%-9.3%, P < .0001). However, the level decreased after PITx and remained low or increased depending on the extent of residual graft function. The GA level at a nadir (median 11.6%, 95% CI 10.8%-13.0%) and the time to reach a nadir (median 43 days, 95% CI 21.7-69.3 days) both correlated with the duration of insulin-independence (rho [ρ] = -.605, P = .0028 and ρ = .662, P = .0008, respectively). The GA level strongly correlated with KG , the glucose disappearance rate during intravenous glucose tolerance testing (ρ = -.76, P < .0001). At post-transplant week (PTW) 3 and at PTW 4, the GA levels in recipients with long-term insulin-independence (>90 days) were significantly lower than those with short-term insulin-independence, which revealed the excellent performance for the prediction of long-term insulin-independence that is comparable to that of porcine C-peptide (historic data). CONCLUSIONS: As a surrogate indicator for graft function, serial measurement of GA may provide Supporting Information to that obtained from conventional monitoring techniques of graft function for assessing porcine islet grafts in NHP models.


Subject(s)
Graft Rejection/immunology , Serum Albumin/biosynthesis , Transplantation, Heterologous , Transplants/surgery , Animals , C-Peptide/blood , Diabetes Mellitus, Experimental/immunology , Glucose Tolerance Test/methods , Glycation End Products, Advanced , Graft Survival/immunology , Immunosuppression Therapy/methods , Islets of Langerhans Transplantation/methods , Macaca mulatta , Retrospective Studies , Swine , Transplantation, Heterologous/methods , Transplants/immunology , Glycated Serum Albumin
10.
Surg Clin North Am ; 97(6): 1419-1424, 2017 Dec.
Article in English | MEDLINE | ID: mdl-29132516

ABSTRACT

The critically ill patient with decompensated cirrhosis has a unique physiology and alterations in albumin that need to be understood to properly resuscitate them and minimize morbidity and mortality. Little data exist on specific resuscitation of the patient with cirrhosis compared with those patients without liver disease. The effectiveness of albumin administration compared with saline administration in common settings, such as large-volume paracentesis, can be extrapolated to the care of the general surgical patient but further studies in this area are warranted. This article enhances the understanding of unique physiology of the patient with decompensated cirrhosis to guide their needs in fluid resuscitation in critical illness.


Subject(s)
Fluid Therapy/methods , Liver Cirrhosis/therapy , Albumins/therapeutic use , End Stage Liver Disease/therapy , Hepatorenal Syndrome/therapy , Humans , Hyponatremia/therapy , Resuscitation/methods , Serum Albumin/biosynthesis , Serum Albumin, Human/metabolism , Sodium Chloride/therapeutic use
11.
PLoS One ; 12(3): e0174611, 2017.
Article in English | MEDLINE | ID: mdl-28350862

ABSTRACT

The possibility of using two different isotopomers, for the incorporation of isotopically labeled amino acids, was explored to enable longitudinal studies of de novo synthesis of two export liver proteins, albumin and fibrinogen. The agreement of the synthesis rates between the two different labels was evaluated along with the reproducibility of repeated experiments using different time intervals. Healthy volunteers were studied in a standardized fed state. Protocol A (n = 10) involved two measurements 48 hours apart. Protocol B (n = 6) involved three measurements at baseline and five hours and then seven days after the initial measurement. De novo synthesis of albumin and fibrinogen by the incorporation of D5-phenylalanine or D8-phenylalanine were measured using the flooding dose technique. Albumin and fibrinogen were isolated from plasma using standard techniques. Fractional and absolute synthesis rates were calculated. Repeated measurements employing the two isotoptomers showed good agreement for albumin fractional synthesis rate after 48 hours (p = 0.92) and after 7 days (p = 0.99), with a coefficient of variation of 5.9% when using the same isotopic label. For fibrinogen, the coefficient of variation for the fractional synthesis rate employing the same isotopic label was 16.6%. Repeated measurements after 48 hours and seven days showed less agreement although there was no statistical difference (P = 0.32 and P = 0.30 respectively). Repeated measurement after five hours showed a statistical significant difference for the fractional synthesis rate of fibrinogen (p = 0.008) but not for albumin (p = 0.12). Repeated measurements of albumin de novo synthesis more than 48 hours apart show acceptable agreement using either one or two different isotopic labels. For fibrinogen the larger intra-individual scatter necessitates larger study groups to detect changes in longitudinal studies. Repeated measurements within 48 hours need to be validated further.


Subject(s)
Amino Acids/metabolism , Fibrinogen/biosynthesis , Liver/metabolism , Serum Albumin/biosynthesis , Adult , Female , Gas Chromatography-Mass Spectrometry , Humans , Isotopes , Male , Middle Aged , Phenylalanine/metabolism , Time Factors , Young Adult
12.
Bioengineered ; 8(5): 600-612, 2017 Sep 03.
Article in English | MEDLINE | ID: mdl-28281868

ABSTRACT

Transforming growth factor-ß1 (TGF-ß1) signaling is involved in cell metabolism, growth, differentiation, carcinoma invasion and fibrosis development, which suggests TGF-ß1 can be treated as a therapeutic target extensively. Because TGF-ß1 receptor type α(TGFBR2) is the directed and essential mediator for TGF-ß1 signals, the extracellular domain of TGFBR2 (eTGFBR2), binding partner for TGF-ß1, has been produced in a series of expression systems to inhibit TGF-ß1 signaling. However, eTGFBR2 is unstable with a short half-life predominantly because of enzymatic degradation and kidney clearance. In this study, a fusion protein consisting of human eTGFBR2 fused at the C-terminal of human serum albumin (HSA) was stably and highly expressed in Chinese Hamster Ovary (CHO) cells. The high and stable expression sub-clones with Ig kappa signal peptide were selected by Western blot analysis and used for suspension culture. After fed-batch culture over 8 d, the expression level of HSA-eTGFBR2 reached 180 mg/L. The fusion protein was then purified from culture medium using a 2-step chromatographic procedure that resulted in 39% recovery rate. The TGF-ß1 binding assay revealed that HSA-eTGFBR2 could bind to TGF-ß1 with the affinity constant (KD of 1.42 × 10-8 M) as determined by the ForteBio Octet System. In addition, our data suggested that HSA-eTGFBR2 exhibited a TGF-ß1 neutralizing activity and maintained a long-term activity more than eTGFBR2. It concluded that the overexpressing CHO cell line supplied sufficient recombinant human HSA-eTGFBR2 for further research and other applications.


Subject(s)
Protein Engineering/methods , Protein Serine-Threonine Kinases/biosynthesis , Protein Serine-Threonine Kinases/chemistry , Receptors, Transforming Growth Factor beta/biosynthesis , Receptors, Transforming Growth Factor beta/chemistry , Recombinant Fusion Proteins/biosynthesis , Recombinant Fusion Proteins/chemistry , Serum Albumin/biosynthesis , Serum Albumin/chemistry , Animals , Binding Sites , CHO Cells , Cricetulus , Genetic Enhancement/methods , Humans , Protein Binding , Receptor, Transforming Growth Factor-beta Type II , Recombinant Fusion Proteins/genetics , Serum Albumin/genetics
13.
Nutr Res ; 37: 46-57, 2017 Jan.
Article in English | MEDLINE | ID: mdl-28215314

ABSTRACT

The reduced/oxidized state of plasma albumin is influenced by many factors, including chronic diseases and strenuous training. Recently, the reduced/oxidized state has also been shown to be associated with dietary protein and energy intakes in rats. We hypothesized that dietary protein intake may modulate the reduced/oxidized state of plasma albumin by altering the rate of albumin synthesis and that the reduced/oxidized state could therefore serve as a novel marker of protein undernutrition. We tested this hypothesis by examining male growing rats placed on a low-protein or energy-restriction diet. In the 4-week experiment, animals fed a low-protein diet (3% casein), whose dietary intakes were lower than those fed control diet (20% casein), showed significant decreases in plasma albumin level and the ratio of the reduced form of albumin to total albumin. Animals given the same amount of control diet as the low-protein diet group (approximately 30% energy restriction) also showed the above decreases, albeit to much more limited extents. The ratio of reduced to total plasma albumin correlated significantly with plasma albumin fractional synthesis rate. When animals were maintained on the low-protein diet for as long as 12 weeks and then fed the control diet for 1 week, the decreased ratio of reduced to total plasma albumin, but not plasma albumin level, resolved rapidly. The reduced/oxidized state of plasma albumin would thus reflect dietary protein status via plasma albumin turnover including the fractional synthesis rate and could prove useful as a sensitive marker of protein undernutrition.


Subject(s)
Diet, Protein-Restricted , Dietary Proteins/pharmacology , Energy Intake , Protein Deficiency/blood , Serum Albumin/metabolism , Animals , Biomarkers/blood , Body Weight , Caloric Restriction , Dietary Proteins/administration & dosage , Male , Oxidation-Reduction , Rats, Wistar , Serum Albumin/biosynthesis
14.
Protein Eng Des Sel ; 30(5): 359-372, 2017 05 01.
Article in English | MEDLINE | ID: mdl-28180900

ABSTRACT

Wnt signaling pathways are required for a wide variety of biological processes ranging from embryonic development to tissue repair and regeneration. Dickkopf-2 (DKK2) is classically defined as a canonical Wnt inhibitor, though it may play a role in activating non-canonical Wnt pathways in the context of endothelial network formation after acute injury. Here we report the discovery of a fusion partner for a DKK2 polypeptide that significantly improves the expression, biochemical properties and pharmacokinetics (PK) of the DKK2 polypeptide. Specifically, human serum albumin (HSA) was identified as a highly effective fusion partner. Substitution of selected amino acid residues in DKK2 designed to decrease heparan sulfate binding by HSA-DKK2 variants, further improved the PK properties of the molecule in rodents. The HSA-DKK2 variants were monomeric, as thermally stable as wild type, and active as measured by their ability to bind to and prevent phosphorylation of the Wnt coreceptor LRP6. Our engineering efforts resulted in potent long-lived variants of the canonical Wnt inhibitor DKK2, applicable for Wnt pathway manipulation either by systematic delivery or focused administration at sites of tissue injury.


Subject(s)
Intercellular Signaling Peptides and Proteins , Low Density Lipoprotein Receptor-Related Protein-6/antagonists & inhibitors , Protein Engineering , Recombinant Fusion Proteins , Serum Albumin , Wnt Proteins/antagonists & inhibitors , Wnt Signaling Pathway/drug effects , Animals , Humans , Intercellular Signaling Peptides and Proteins/biosynthesis , Intercellular Signaling Peptides and Proteins/chemistry , Intercellular Signaling Peptides and Proteins/isolation & purification , Intercellular Signaling Peptides and Proteins/pharmacology , Mice , Recombinant Fusion Proteins/biosynthesis , Recombinant Fusion Proteins/chemistry , Recombinant Fusion Proteins/isolation & purification , Recombinant Fusion Proteins/pharmacology , Serum Albumin/biosynthesis , Serum Albumin/chemistry , Serum Albumin/isolation & purification , Serum Albumin/pharmacology
15.
Bioengineered ; 8(3): 256-264, 2017 May 04.
Article in English | MEDLINE | ID: mdl-27753513

ABSTRACT

Hepatocyte growth factor (HGF) is a potent multi-functional protein that stimulates proliferation, survival, motility, scattering and differentiation during growth and development, and has been considered to be a potential therapeutic agent for the treatment of a number of intractable diseases. The aim of this study was to enhance the expression of recombinant fusion protein HSA-HGF (R494E) in CHO cells by inhibiting the intracellular ubiquitin ligase activity. The high stable expression sub-clones with different signal peptides were selected by western blot (WB) analysis and used for suspension culture. We found that the expression of fusion protein HSA-HGF (R494E) on day 3 achieved 50 mg/L during the 8 day culture process, a large number of fusion proteins were intracellular degradated by ubiquitination pathway during day 4 to day 8. Furthermore, ubiquitin ligase inhibitor, thalidomide, was added in culture process, and resulted in efficient and stable secretion of HSA-HGF (R494E) in CHO cells. According to biological activity assays, HSA-HGF (R494E) possessed various biological activities similar to native HGF. In conclusion, innhibition of intracellular ubiquitin ligase activity was successfully improve the expression of biologically active fusion protein HSA-HGF (R494E) in CHO cells. Our data may be beneficial to enhance the production of other therapeutic proteins in fed-batch culture.


Subject(s)
Hepatocyte Growth Factor/biosynthesis , Hepatocyte Growth Factor/genetics , Recombinant Proteins/biosynthesis , Serum Albumin/biosynthesis , Serum Albumin/genetics , Ubiquitin-Protein Ligases/antagonists & inhibitors , Animals , CHO Cells , Cricetulus , Down-Regulation , Enzyme Activation , Protein Engineering/methods , Recombinant Proteins/genetics , Ubiquitin-Protein Ligases/metabolism
16.
Crit Care ; 20(1): 370, 2016 11 15.
Article in English | MEDLINE | ID: mdl-27846908

ABSTRACT

BACKGROUND: Better knowledge of albumin kinetics is needed to define the indications for albumin use in clinical practice. This study involved two approaches: the synthesis rate and transcapillary escape rate of albumin were measured simultaneously at different levels of plasma albumin concentration in relation to acute inflammation and surgery; and two different tracers were compared to determine plasma volume and the transcapillary escape rate. METHODS: Healthy volunteers (n = 10), patients with acute inflammatory abdominal disease (n = 10), and patients undergoing elective pancreatic resection (n = 10) were studied. The albumin synthesis rate was measured by the incorporation of deuterium-labeled phenylalanine. Plasma volume and the transcapillary escape rate were assessed using 123I-labeled and 125I-labeled albumin. RESULTS: A 50 % elevated de-novo albumin synthesis rate was seen in patients with acute inflammation and marked hypoalbuminemia, while patients with marginal hypoalbuminemia before the start of surgery had a normal albumin synthesis rate. The transcapillary escape rate was elevated intraoperatively during the reconstructive phase of pancreatic surgery, when plasma albumin was decreased but stable. In acute inflammation with marked hypoalbuminemia, the transcapillary escape rate was no different from normal. 123I-labeled and 125I-labeled albumin were found exchangeable for plasma volume determinations, but could be used only in groups of patients for the transcapillary escape rate. CONCLUSIONS: This observational study illustrates the limited information contained in albumin plasma concentrations to reflect albumin kinetics. On the contrary, single measurements of the synthesis rate and/or transcapillary escape rate of albumin obviously cannot explain the plasma level of albumin or the changes seen in plasma albumin concentration. TRIAL REGISTRATION: www.clinicaltrials.gov , study number NCT01686776 . Registered 13 September 2012.


Subject(s)
Capillary Permeability/physiology , Hypoalbuminemia/metabolism , Intraoperative Complications/metabolism , Plasma Volume/physiology , Serum Albumin/biosynthesis , Adult , Aged , Female , Humans , Hypoalbuminemia/diagnosis , Hypoalbuminemia/etiology , Inflammation/diagnosis , Inflammation/metabolism , Intraoperative Complications/diagnosis , Intraoperative Complications/etiology , Male , Middle Aged , Oximetry/methods , Serum Albumin/metabolism
17.
Pak J Pharm Sci ; 29(5): 1555-1563, 2016 Sep.
Article in English | MEDLINE | ID: mdl-27731812

ABSTRACT

Doxorubicin and Cyclophosphamide (AC protocol) combination is usually considered as a first line therapy in newly diagnosed breast cancer patients. Thus, a retrospective observational study was conducted to monitor the effect of AC protocol on liver synthetic functions and production of plasma proteins in breast cancer patients, reporting to specialized cancer care hospital of Lahore, Pakistan. A total of 75 patients (n=75) on AC protocol with breast cancer were observed in this study. The patient data including age, gender, body surface area, dosage, disease status and laboratory biochemical values were recorded by reviewing historical treatment records. Pre-treatment values were taken as baseline values for albumin, globulin, blood urea nitrogen (BUN), albumin/globulin (A/G) ratio and total proteins. The baseline values were compared after each cycle of by applying ANOVA using statistical tool SPSS® version 21. The plasma levels of blood urea nitrogen (BUN), total protein and globulin dropped significantly (p<0.05) in patients of all age groups. However, the albumin levels were not significantly changed (p>0.05). The A/G ratio level increased (p<0.05) as a result of reduction in globulin levels. Significant changes in plasma protein levels were observed in the elderly patients (50 to 65 years) than patients between 20 to 50 years of age. AC protocol impairs liver synthetic functions as observed by decreased blood urea nitrogen (BUN) and plasma protein levels.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/adverse effects , Blood Proteins/biosynthesis , Breast Neoplasms/drug therapy , Chemical and Drug Induced Liver Injury/etiology , Cyclophosphamide/adverse effects , Doxorubicin/adverse effects , Liver/drug effects , Adult , Age Factors , Aged , Biomarkers/blood , Blood Urea Nitrogen , Breast Neoplasms/diagnosis , Chemical and Drug Induced Liver Injury/blood , Chemical and Drug Induced Liver Injury/diagnosis , Cyclophosphamide/administration & dosage , Doxorubicin/administration & dosage , Female , Globulins/biosynthesis , Humans , Liver/metabolism , Middle Aged , Pakistan , Retrospective Studies , Serum Albumin/biosynthesis , Serum Albumin, Human , Time Factors , Treatment Outcome , Young Adult
18.
Appl Microbiol Biotechnol ; 100(17): 7565-75, 2016 Sep.
Article in English | MEDLINE | ID: mdl-27115755

ABSTRACT

The 14-amino acid (IEGPTLRQWLAARA) thrombopoietin mimetic peptide (TMP) shares no sequence homology with native thrombopoietin (TPO). When dimerized, it displays a high-binding affinity for the TPO receptor and has equipotent bioactivity with recombinant human TPO (rhTPO) in stimulating proliferation and maturation of megakaryocytes in vitro. However, TMP is limited for clinical usage because of its short half-life in vivo. In this study, fusion proteins that composed of tandem dimer of TMP (dTMP) genetically fused at the C- or N-terminus of human serum albumin (HSA) were separately expressed in Chinese hamster ovary (CHO) cells. In vitro bioactivity assays showed that purified fusion proteins promoted the proliferation of megakaryocytes in a dose-dependent manner and activated signal transducer and activator of transcription (STAT) pathway in TPO receptor-dependent manner. Following subcutaneous administration, both HSA-dTMP and dTMP-HSA significantly elevated peripheral platelet counts in normal mice in a dose-dependent manner. In addition, fusion with HSA successfully prolonged dTMP half-life in mice. However, when HSA was fused at the C-terminus of dTMP, the bioactivity of dTMP-HSA was about half of that of HSA-dTMP. In conclusion, these results suggested that HSA/dTMP fusion proteins might be potential drugs for thrombocytopenia and, when HSA was fused at the N-terminus of dTMP, the fusion protein had a higher activity.


Subject(s)
Cell Proliferation/drug effects , Megakaryocytes/metabolism , Peptides/genetics , Recombinant Fusion Proteins/genetics , Recombinant Fusion Proteins/pharmacology , Serum Albumin/genetics , Animals , CHO Cells , Cell Line , Cricetinae , Cricetulus , Enzyme Activation/drug effects , Female , Gene Expression , Humans , Male , Megakaryocytes/drug effects , Mice , Peptides/metabolism , Platelet Count , Recombinant Fusion Proteins/biosynthesis , STAT Transcription Factors/metabolism , Serum Albumin/biosynthesis , Serum Albumin/metabolism , Thrombocytopenia/drug therapy
19.
Methods Mol Biol ; 1357: 375-81, 2016.
Article in English | MEDLINE | ID: mdl-25417065

ABSTRACT

Here, we describe a procedure of human iPS cells differentiation into the definitive endoderm, further into albumin-expressing and albumin-secreting hepatocyte, using M15, a mesonephros- derived cell line. Approximately 90 % of human iPS cells differentiated into SOX17-positive definitive endoderm then approximately 50 % of cells became albumin-positive cells, and secreted ALB protein. This M15 feeder system for endoderm and hepatic differentiation is a simple and efficient method, and useful for elucidating molecular mechanisms for hepatic fate decision, and could represent an attractive approach for a surrogate cell source for pharmaceutical studies.


Subject(s)
Cell Culture Techniques/methods , Cellular Reprogramming Techniques/methods , Cellular Reprogramming , Endoderm/cytology , Hepatocytes/cytology , Induced Pluripotent Stem Cells/cytology , Cell Line , Cell Lineage , Cells, Cultured , Culture Media/pharmacology , Humans , Mitomycin/pharmacology , SOXF Transcription Factors/analysis , Serum Albumin/biosynthesis
20.
Sci Rep ; 5: 16705, 2015 Nov 12.
Article in English | MEDLINE | ID: mdl-26560187

ABSTRACT

Precise genome modification in large domesticated animals is desirable under many circumstances. In the past it is only possible through lengthy and burdensome cloning procedures. Here we attempted to achieve that goal through the use of the newest genome-modifying tool CRISPR/Cas9. We set out to knockin human albumin cDNA into pig Alb locus for the production of recombinant human serum albumin (rHSA). HSA is a widely used human blood product and is in high demand. We show that homologous recombination can occur highly efficiently in swine zygotes. All 16 piglets born from the manipulated zygotes carry the expected knockin allele and we demonstrated the presence of human albumin in the blood of these piglets. Furthermore, the knockin allele was successfully transmitted through germline. This success in precision genomic engineering is expected to spur exploration of pigs and other large domesticated animals to be used as bioreactors for the production of biomedical products or creation of livestock strains with more desirable traits.


Subject(s)
CRISPR-Cas Systems , DNA, Complementary , Gene Knock-In Techniques , Genetic Loci , Serum Albumin/biosynthesis , Serum Albumin/genetics , Zygote/metabolism , Alleles , Animals , Gene Expression , Gene Order , Gene Targeting , Humans , Swine
SELECTION OF CITATIONS
SEARCH DETAIL
...