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1.
Gene Ther ; 21(2): 158-67, 2014 Feb.
Article in English | MEDLINE | ID: mdl-24285215

ABSTRACT

Lung cancer still remains to be challenged by novel treatment modalities. Novel locally targeted routes of administration are a methodology to enhance treatment and reduce side effects. Intratumoral gene therapy is a method for local treatment and could be used either in early-stage lung cancer before surgery or at advanced stages as palliative care. Novel non-viral vectors are also in demand for efficient gene transfection to target local cancer tissue and at the same time protect the normal tissue. In the current study, C57BL/6 mice were divided into three groups: (a) control, (b) intravenous and (c) intatumoral gene therapy. The novel 2-Diethylaminoethyl-Dextran Methyl Methacrylate Copolymer Non-Viral Vector (Ryujyu Science Corporation) was conjugated with plasmid pSicop53 from the company Addgene for the first time. The aim of the study was to evaluate the safety and efficacy of targeted gene therapy in a Lewis lung cancer model. Indeed, although the pharmacokinetics of the different administration modalities differs, the intratumoral administration presented increased survival and decreased distant metastasis. Intratumoral gene therapy could be considered as an efficient local therapy for lung cancer.


Subject(s)
Antineoplastic Agents/adverse effects , Carcinoma, Lewis Lung/therapy , DEAE-Dextran/adverse effects , Methylmethacrylate/adverse effects , Neoplasm Metastasis/therapy , Tumor Suppressor Protein p53/metabolism , Administration, Intravenous , Animals , Antineoplastic Agents/administration & dosage , Carcinoma, Lewis Lung/pathology , Cell Line, Tumor , DEAE-Dextran/administration & dosage , Genetic Therapy/adverse effects , Genetic Therapy/methods , Methylmethacrylate/administration & dosage , Mice , Mice, Inbred C57BL , Plasmids/administration & dosage
2.
Eur Surg Res ; 47(1): 45-51, 2011.
Article in English | MEDLINE | ID: mdl-21606651

ABSTRACT

BACKGROUND: Bevacizumab is a monoclonal antibody targeted at vascular endothelial growth factor (VEGF) to treat advanced colorectal cancer as well as other malignancies, but the ideal time point for its administration in patients scheduled for surgery is not well defined due to serious concerns regarding possible side effects on wound healing. Therefore, we conducted an experimental study in rats to clarify this issue. METHODS: Four groups of 10 Wistar rats each underwent a 4-cm midline laparotomy and closure of the wound in 2 layers. In the treatment groups (A and B), bevacizumab (Avastin(®)) received a single dose of 5 mg/kg i.p., and an equal amount of saline was given to the control groups (C and D). Groups A and C were sacrificed on the 7th postoperative day, and groups B and D on the 14th postoperative day. Wounds were inspected by two independent observers upon sacrifice and results were recorded; wound tissues were sent for histology to assess the degree of fibrosis and measurement of tissue hydroxyproline levels. Serum levels of endothelin-1, C-reactive protein, pro-oxidant/antioxidant balance and carbonylated proteins were also determined. For statistical analysis, the Mann-Whitney U test was used. RESULTS: Wound healing did not differ among groups both on the 7th and the 14th postoperative days, and there was also no significant difference regarding the degree of inflammation, fibroblast proliferation and collagen synthesis, as well as hydroxyproline and biochemical marker levels among the groups. CONCLUSIONS: Intraperitoneal bevacizumab administered intraoperatively does not significantly affect abdominal wound healing in rats.


Subject(s)
Angiogenesis Inhibitors/adverse effects , Antibodies, Monoclonal/adverse effects , Wound Healing/drug effects , Abdomen/pathology , Abdomen/physiopathology , Angiogenesis Inhibitors/administration & dosage , Animals , Antibodies, Monoclonal/administration & dosage , Antibodies, Monoclonal, Humanized , Bevacizumab , Carrier Proteins/blood , Endothelin-1/blood , Hydroxyproline/metabolism , Injections, Intraperitoneal , Male , Oxidative Stress/drug effects , Rats , Rats, Wistar , Vascular Endothelial Growth Factor A/antagonists & inhibitors , Wound Healing/physiology
3.
Transplant Proc ; 41(10): 4340-4, 2009 Dec.
Article in English | MEDLINE | ID: mdl-20005395

ABSTRACT

INTRODUCTION: Adipose tissue is recognized as an important source of postnatal mesenchymal stem cells for generative medicine applications. Moreover, cord blood stem cells have been shown to contain pluripotent stem cells called unrestricted somatic stem cells (USSCs). However, this population is rare and cannot be generated from every cord blood sample. In this study, we have presented a new method of co-culture of adipose-derived stem cells (ADPCs) and cord blood stem cells that results in pluripotent differentiation. MATERIALS AND METHODS: ADPCs were obtained from a piece of adipose tissue after treatment with 0.075% collagenase, which was subsequently inactivated with DMEM/10% FBS. The cellular pellet of centrifugation was plated at 5-7 x 10(6) cells/mL in T25 culture flasks in a low-glycose DMEM with 30% FCS. Cord blood stem cells were obtained by centrifugation following double-processing in the presence of 2% HES 200/0.5 and plated at 5-7 x 10(6) cells/mL in the same medium. To investigate the crucial role of ADPCs in pluripotent cord blood differentiation, we added a ADPCS as (1 x 10(4) cells/mL) to the cord blood cultures and analyzed the contribution of ADPCs using a microscope as well as with flow cytometry. RESULTS: After only 3 days, adherent cells (USSC colonies) of fibroblastic morphology were detected in all co-cultured samples, whereas this was observed later or not at all in the non-co-cultured samples. The greater density of colonies in the co-coltured samples was another point. Hematopoietic CD45 cells were no longer detected after the first passage. Pluripotent stem cells were obtained from all co-cultured samples that contained stem cells positive for CD29, CD44, CD49e, CD90, CD105, CD51 Stro, and C-kit antibodies but negative for CD34, CD45, CD133, and glycophorin A. CONCLUSION: Addition of ADPCs was crucial to generate pluripotent-derived stem cells from cord blood samples. This double culture may be a useful tool for a universal allogeneic stem cell source for tissue repair or regeneration.


Subject(s)
Adipose Tissue/cytology , Adipose Tissue/physiology , Fetal Blood/cytology , Pluripotent Stem Cells/cytology , Stem Cells/cytology , Blood Platelets/cytology , Blood Platelets/physiology , Cell Adhesion , Cell Differentiation , Cells, Cultured , Coculture Techniques , Female , Fibroblasts/cytology , Fibroblasts/physiology , Flow Cytometry/methods , HIV-1/isolation & purification , HIV-2/isolation & purification , Hepacivirus/isolation & purification , Hepatitis B Surface Antigens/blood , Humans , Placenta/cytology , Pluripotent Stem Cells/physiology , Polymerase Chain Reaction , Pregnancy , Tissue Banks/standards
4.
Klin Monbl Augenheilkd ; 226(4): 264-71, 2009 Apr.
Article in English | MEDLINE | ID: mdl-19384780

ABSTRACT

PURPOSE: We report the clinical, morphological, and ultrastructural findings of 13 consecutively explanted opacified Hydroview(R) (hydrogel) intraocular lenses (IOLs). Our purpose was to provide a comprehensive account on the possible factors involved in late postoperative opacification of these IOLs. PATIENTS AND METHODS: Thirteen consecutive opacified hydrogel IOLs (Hydroview H 60 M, Bausch & Lomb) were explanted due to the significant visual impairment they caused. The IOLs underwent macroscopical examination, transmission electron microscopy (TEM), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), and electrophoresis for protein detection. Three unused control Hydroview IOLs served for comparison. RESULTS: Macroscopical examination showed a diffuse or localized grey-whitish opacification within the IOL optic. TEM confirmed the presence of lesions inside the optic in all the explanted IOLs and revealed 3 patterns of deep deposits: a) diffuse, thick, granular, electron-dense ones; b) small, thin, lattice-like ones, with prominent electron-lucent areas; and c) elongated electron-dense formations surrounded by electron-lucent halos. SEM showed surface deposits on four IOLs. EDS revealed oxygen and carbon in all IOLs and documented calcium, phosphorus, silicon and/or iron in the deposits. Two of the patients with iron in their IOLs had eye surgery prior to their phacoemulsification. Iron correlated well with the second TEM pattern of deep lesions, whereas calcium with the third TEM pattern. No protein bands were detected on electrophoresis. Control lenses did not show any ultrastructural or chemical abnormality. CONCLUSIONS: The present study supports the presence of chemical alterations inside the polymer of the optic in late postoperative opacification of Hydroview IOLs. This opacification does not follow a unique pathway but may present under different ultrastructular patterns depending on the responsible factors. Mechanical stress during surgery may initiate a sequence of events where ions such as calcium, phosphorus, silicon, and/or iron, participate in a biochemical cascade that leads to gradual alteration of the polymer network. Intraocular inflammation due to previous operation may be a factor inducing opacification through increase of iron-binding capacity in the aqueous humour. Calcification accounts only partially for the opacification noted in this type of IOL.


Subject(s)
Corneal Opacity/diagnosis , Corneal Opacity/etiology , Device Removal , Hydrogels/adverse effects , Lenses, Intraocular/adverse effects , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Treatment Outcome
5.
Transplant Proc ; 39(10): 3380-4, 2007 Dec.
Article in English | MEDLINE | ID: mdl-18089389

ABSTRACT

The amount of newborn blood that can be collected from a single cord donor is limited, but a significant amount remains in the placenta. We used a simplified perfusion method to collect this additional blood. Umbilical cord blood from 15 newborns was collected before placental delivery by umbilical vein puncture. After delivery, the placenta was placed on sterile gauze and 63 mL of citrate-phosphate-dextrose-adenine anticoagulant were injected into the umbilical vein that was then clamped near the placenta. The placenta was gently massaged, hung over a sterile vessel, and the umbilical cord cut sterilely near the embryonic surface. Additional blood was collected into the sterile vessel by pressuring a gauze bag around the placenta. We assessed the contribution of this second fraction to the total volume, total nucleated cell (NC), CD34+, hematopoietic progenitors cell, and colony forming unit count and bacterial contamination risk. The total collected volume was 127.3 mL (range 92-170) and the NC content was 1.6+/-0.73x10(9). The mean second fraction contribution from 15 units to the total nucleated and mononuclear cell content was 54+/-9.87% and 54+/-9.52%, respectively. The added percentage of CD34+ and hematopoietic progenitor cells was 54.3+/-10.35% and 46.7+/-11.5%, respectively, while the additional percentages of colony forming-granulocyte macrophage and colony forming-erythroid in the second fraction were 43.2+/-5.5% and 39.8+/-4.3%, respectively, indicating that the cells collected after placental perfusion (second fraction) had similar HPC content and in vitro hematopoietic potential. The method did not increase the risk of bacterial contamination.


Subject(s)
Cord Blood Stem Cell Transplantation , Tissue and Organ Harvesting/methods , Antigens, CD/blood , Antigens, CD34/blood , Colony-Forming Units Assay , Hematopoietic Stem Cells/cytology , Humans , Infant, Newborn , Umbilical Veins
6.
Cytotherapy ; 9(7): 654-9, 2007.
Article in English | MEDLINE | ID: mdl-17917886

ABSTRACT

BACKGROUND: For the application of umbilical cord blood (UCB) units as hematopoietic grafts, a dose of 3.7 x 10(7) nucleated cells (NC)/kg body weight is required. NC can be lost during volume-reduction processing and during thawing. A novel modification of the double-processing protocol with the aim of minimizing NC loss is described and evaluated. METHODS: One-hundred and fifty UCB were collected. The volume was reduced by a centrifugation step following double-processing in the presence of 2% HES 200/0.5. Pre- and post-processing cell counts and platelet parameters were measured with an automatic counter. The number of viable CD34+ hemopoietic stem cells was measured by flow cytometry. In 25 of the samples, colony-forming units (CFU) were also determined. The same samples were thawed 6 months after cryopreservation and re-evaluated. RESULTS: The volume was reduced to 6 +/- 1.5 mL. The recovery of NC, MNC, CD34+ hemopoietic stem cells, RBC depletion and CFU following double-processing was 93.6 +/- 3.2%, 95.8 +/- 2.2%, 98.4 +/- 1.5%, 96.8 +/- 1.1% and 107.1 +/- 6.1% (for 25 samples), respectively. The post-thaw recoveries of NC, MNC, CD34+ hemopoietic stem cells and CFU (for 25 samples) were 78.6 +/- 5.4%, 90.8 +/- 4.4%, 96.4 +/- 2.5%, 89.1 +/- 4.1%, respectively. No post-thaw cell aggregation was observed. A significant (P<0.05) post-thaw loss of platelets and signs of platelet activation was observed. DISCUSSION: The protocol uses non-expensive equipment and clinically approved materials and results in samples that can be used in patients with a mean weight of 32.7 kg.


Subject(s)
Blood Preservation/methods , Cryopreservation/methods , Fetal Blood/cytology , Antigens, CD34 , Blood Platelets/cytology , Cell Survival , Colony-Forming Units Assay , Cryoprotective Agents , Hematopoietic Stem Cells/cytology , Humans , Infant, Newborn
7.
Int Angiol ; 26(1): 38-48, 2007 Mar.
Article in English | MEDLINE | ID: mdl-17353887

ABSTRACT

AIM: A small number of left internal thoracic artery (LITA) grafts are occluded at 3 years after the operation or show more than 50% stenosis of the lumen. The purpose of this study is to examine factors related to the morphology of the wall and to the function of the cell population of LITA grafts before implantation, in order to evaluate their quality and the viability, in a follow-up examination. METHODS: Fifteen LITA grafts were examined with light microscopy, for their morphology, endothelial cell coverage, apoptosis and cell proliferation, scanning electron microscopy and transmission electron microscopy. RESULTS: Increase of the thickness of the intima (14.21+/-1.28 mm), mean thickness of media 160.37+/-11.97 mm, detachment of intima from media, presence of foam cells in the media, low endothelial coverage (40.638+/-16.864), increase of apoptosis in intima (46.38+/-13.46), sub-intima (29.3+/-8.54), media (34.91+/-6.05) and adventitia (40.21+/-5.36), blood cells penetration of the intima through disruptions between endothelial cells are findings of LITA grafts before implantation. Cell proliferation was not detected in the wall of any graft. Follow-up examination 6 months and 2.5 years after the operation showed normal function of LITA grafts. CONCLUSIONS: Besides of the wall injury and the initiated atherosclerotic lesions, LITA grafts are well functioning at the time of the follow-up examination. Maybe our findings are related to the later occlusion of the referred in the literature small number of LITA grafts.


Subject(s)
Apoptosis , Coronary Artery Bypass/methods , Graft Occlusion, Vascular/pathology , Mammary Arteries/pathology , Mammary Arteries/transplantation , Tunica Intima/pathology , Tunica Media/pathology , Blood Platelets/ultrastructure , Cell Proliferation , Cell Survival , Endothelial Cells/ultrastructure , Female , Foam Cells/pathology , Follow-Up Studies , Humans , In Situ Nick-End Labeling , Male , Microscopy, Electron, Scanning , Microscopy, Electron, Transmission , Time Factors , Treatment Outcome
8.
Eur J Anaesthesiol ; 23(2): 130-5, 2006 Feb.
Article in English | MEDLINE | ID: mdl-16426467

ABSTRACT

BACKGROUND AND OBJECTIVE: We conducted this study in order to evaluate the potential myotoxic effects of ropivacaine after single injection in rats and the time-course of the possible damage. METHODS: One hundred and twenty-eight male Wistar rats were allocated to four different groups. The first three groups received intramuscular injections with ropivacaine 0.75%, ropivacaine 0.5% and normal saline, respectively, into the right tibialis anterior muscle. The fourth group received needle puncture without injection. Eight rats from each group were sacrificed 2, 4, 7 and 30 days after injection. Samples were blindly examined under light microscope for evidence of myotoxicity, scored as 0 = no damage to 3 = myonecrosis and statistically analysed. Samples obtained 7 days after injection were also examined under transmission electron microscope. RESULTS: Ropivacaine 0.75% and ropivacaine 0.5% caused extensive destruction to muscles fibres, compared to saline or needle on days 2, 4 and 7. Statistically significant differences were found in muscle damage by drug injections among all groups except for saline vs. needle groups. Thirty days after injections all sample appearances had returned to normal. CONCLUSIONS: Ropivacaine after single intramuscular injection caused reversible muscle damage in a dose-dependent manner.


Subject(s)
Amides/toxicity , Anesthetics, Local/toxicity , Muscle, Skeletal/drug effects , Amides/administration & dosage , Anesthetics, Local/administration & dosage , Animals , Dose-Response Relationship, Drug , Hindlimb , Injections, Intramuscular , Male , Microscopy, Electron, Transmission , Muscle, Skeletal/pathology , Muscle, Skeletal/ultrastructure , Necrosis , Rats , Rats, Wistar , Ropivacaine
9.
J Nucl Med ; 38(12): 1940-4, 1997 Dec.
Article in English | MEDLINE | ID: mdl-9430474

ABSTRACT

UNLABELLED: The synthetic laminin pentapeptide tyrosyl-isoleucyl-glycyl-seryl-arginine (YIGSR) binds to a metastasis associated high-affinity laminin receptor. The aim of this study was to investigate if the radiolabeled peptide can be considered as a basis for a potential tumor-imaging radiopharmaceutical. METHODS: Iodine-131-labeled YIGSR was injected in mice inoculated with Lewis Lung carcinoma, as well as in normal controls. The experimental animals were imaged on a gamma camera 10 hr after peptide administration. The same peptide was also labeled with 125I and administered to tumor-bearing and normal mice. At various time-points after peptide administration, the experimental animals were killed, and the radioactivity in the tumor, lung, liver and spleen was measured. Microscopic autoradiography was performed in histological sections of the same tissues. RESULTS: The tumor and the spleen of tumor-bearing animals were imaged on a gamma camera. No significant blood-pool background was detected. No other organ except urinary bladder and thyroid was imaged in normal animals. The peptide was retained on tumor and spleen of tumor-bearing animals. Twenty-four hours after peptide administration, the tumor, lung, liver and spleen of animals with tumors contained significantly more radioactivity than the same tissues of equally treated normal controls. The radiolabeled peptide YIGSR was detected by microscopic autoradiography on the surface of certain tumor cells, but not on the surface of any normal cell. CONCLUSION: Although extensive research is still required, the peptide YIGSR can be considered as a basis for the development of a receptor specific radiopharmaceutical useful for the in vivo estimation of the metastatic potential of tumors. This radiopharmaceutical may be helpful in staging and prognostic-related decisions on cancer treatment.


Subject(s)
Carcinoma, Lewis Lung/diagnostic imaging , Iodine Radioisotopes , Lung Neoplasms/diagnostic imaging , Oligopeptides , Radiopharmaceuticals , Animals , Autoradiography , Carcinoma, Lewis Lung/pathology , Carcinoma, Lewis Lung/secondary , Laminin , Lung/pathology , Lung Neoplasms/pathology , Lung Neoplasms/secondary , Mice , Mice, Inbred C57BL , Neoplasm Transplantation , Radionuclide Imaging
10.
Invasion Metastasis ; 16(6): 322-9, 1996.
Article in English | MEDLINE | ID: mdl-9371232

ABSTRACT

It has been reported that metastatic melanoma cell lines selectively bind in vitro with the synthetic laminin pentapeptide tyrosyl-isoleucyl-glycyl-seryl-arginine (YIGSR). The aim of this study was to investigate whether the same peptide can bind on melanoma cells in vivo as well. Iodine-125-labeled YIGSR was administered to B16 melanoma-bearing animals. Microscopic autoradiography of tumor and organ sections taken 24 h after peptide administration showed that the peptide did accumulate on the surface of certain tumor cells. The peptide binding cells were frequent in metastatic sites and tumors grown for 24 days and rare in tumors grown for 10 days. A similarly radiolabeled control pentapeptide (peptide DRLKY) did not bind to any tumor cell. It is suggested that the YIGSR binding tumor cells may represent a distinct melanoma cell population with a high metastatic potential.


Subject(s)
Antineoplastic Agents/metabolism , Melanoma, Experimental/metabolism , Oligopeptides/metabolism , Animals , Autoradiography , Iodine Radioisotopes , Melanoma, Experimental/pathology , Mice , Mice, Inbred C57BL , Neoplasm Transplantation
12.
Diabetes ; 39(7): 807-14, 1990 Jul.
Article in English | MEDLINE | ID: mdl-2113013

ABSTRACT

Laminin, a basement membrane protein derived from the matrix of the Engelbreth-Holm-Swarm murine tumor, was nonenzymatically glycosylated in vitro in the presence of increasing glucose concentrations. The amount of glucose incorporated per laminin molecule was shown to be proportional to the molarity of glucose used. Nonenzymatic glycosylation resulted in formation of cross-links and alterations of the cruciform shape of laminin molecules; these alterations were dramatic when high concentrations of glucose were used. One of the functions of laminin, the process of self-assembly, was shown to be impaired after in vitro nonenzymatic glycosylation. Glucose incorporation resulted in a dramatic decrease of long-to-long laminin dimers, which normally form during the initial steps of assembly. Furthermore, nonenzymatic glycosylation of laminin reduced its ability to self-associate into complexes larger than dimers, as judged by turbidimetry. The observed decrease of maximal turbidity was proportional to the degree of nonenzymatic glycosylation. Aminoguanidine, which has been suggested to inhibit cross-link formation, was shown to restore to a large extent the shape of laminin, the percentage of long-to-long arm dimers, and the maximal turbidity when included in the mixtures of laminin and glucose. These data suggest that structural and functional alterations of laminin may be primarily due to formation of cross-links. Such modifications of laminin (along with our basement membrane components) may contribute to the morphological and physiological changes observed in basement membranes under diabetic conditions.


Subject(s)
Laminin/metabolism , Animals , Basement Membrane/metabolism , Glucose/metabolism , Glycosylation , Guanidines/pharmacology , Kinetics , Laminin/isolation & purification , Laminin/ultrastructure , Lysine , Mice , Neoplasms, Experimental/metabolism , Nephelometry and Turbidimetry
13.
J Biol Chem ; 264(30): 17971-8, 1989 Oct 25.
Article in English | MEDLINE | ID: mdl-2808359

ABSTRACT

Laminin, a major basement membrane glycoprotein, interacts with many basement membrane- and cell surface-associated heparin-like macromolecules. In order to understand these interactions better, we have tried to map heparin-binding sites on laminin precisely. Electron microscopy revealed three major heparin-binding sites: 1) on the globule of the long arm; 2) on the outer globule of the short arms; and 3) on the inner globule of the short arms. Elution of heparin bound to a laminin affinity column with a linear salt gradient produced three peaks at 0.15, 0.17, and 0.20 M NaCl. When the laminin-heparin interaction was examined in the presence of increasing salt concentrations by the technique of rotary shadowing, the weakest binding was assigned to the inner globule of the short arms and the strongest to the globule of the long arm. One peptide termed AC15, with the sequence Arg-Ile-Gln-Asn-Leu-Leu-Lys-Ile-Thr-Asn-Leu-Arg-Ile-Lys-Phe-Val-Lys from the B1 chain, was identified as a heparin-binding sequence localized on the outer globule of the lateral short arm. Because the two stronger heparin-binding sites were mapped in domains participating in laminin self-association, the effect of heparin on this phenomenon was examined using turbidity and electron microscopy. At low heparin concentrations, laminin oligomer and polymer formation was slightly enhanced. At high heparin concentrations, a drastic inhibition of polymerization was observed, and laminin was detected to be mainly monomeric in rotary-shadowed samples. These results suggest that local variation in the concentration of heparin-like macromolecules might be a crucial factor in determining the association of matrix macromolecules and therefore the structure of basement membranes.


Subject(s)
Heparin/metabolism , Laminin/metabolism , Amino Acid Sequence , Animals , Binding Sites , Chromatography, Affinity , Heparin/isolation & purification , Laminin/isolation & purification , Laminin/ultrastructure , Macromolecular Substances , Mice , Molecular Sequence Data , Neoplasms, Experimental/metabolism
14.
J Biol Chem ; 264(4): 2313-23, 1989 Feb 05.
Article in English | MEDLINE | ID: mdl-2914908

ABSTRACT

Three distinctive heparin-binding sites were observed in type IV collagen by the use of rotary shadowing: in the NC1 domain and at distances 100 and 300 nm from the NC1 domain. Scatchard analysis indicated different affinities for these sites. Electron microscopic analysis of heparin-type IV collagen interaction with increasing salt concentrations showed the different affinities to be NC1 greater than 100 nm greater than 300 nm. The NC1 domain bound specifically to chondroitin/dermatan sulfate side chains as well. This binding was observed at the electron microscope and in solid-phase binding assays (where chondroitin sulfate could compete for the binding of [3H]heparin to NC1-coated substrata). The triple helix-rich, rod-like domain of type IV collagen did not bind to chondroitin/dermatan sulfate side chains. In solid-phase binding assays only heparin could compete for the binding of [3H]heparin to this domain. In order to more precisely map potential heparin-binding sites in type IV collagen, we chemically synthesized 17 arginine- and lysine-containing peptides from the alpha 1(IV) and alpha 2(IV) chains. Three peptides from the known sequence of the alpha 1(IV) and alpha 2(IV) chains were shown to specifically bind heparin: peptide Hep-I (TAGSCLRKFSTM), from the alpha 1(NC1) chain, peptide Hep-II (LAGSCLARFSTM), a peptide corresponding to the same sequence in peptide Hep-I from the alpha 2 (NC1) chain, and peptide Hep-III (GEFYFDLRLKGDK) which contained an interruption of the triple helical sequence of the alpha 1(IV) chain at about 300 nm from the NC1 domain, were demonstrated to bind heparin in solid-phase binding assays and compete for the binding of [3H]heparin to type IV collagen-coated substrata. Therefore, each of these peptides may represent a potential heparin-binding site in type IV collagen. The mapping of the binding of heparin or related structures, such as heparan sulfate proteoglycan, to specific sequences of type IV collagen could help the understanding of several structural and functional properties of this basement membrane protein as well as interactions with other basement membrane and/or cell surface-associated macromolecules.


Subject(s)
Collagen/metabolism , Heparin/metabolism , Amino Acid Sequence , Binding Sites , Binding, Competitive , Collagen/ultrastructure , Indicators and Reagents , Kinetics , Microscopy, Electron , Oligopeptides/chemical synthesis , Protein Binding , Protein Conformation
15.
Hum Hered ; 39(3): 141-9, 1989.
Article in English | MEDLINE | ID: mdl-2591977

ABSTRACT

A new deficient glucose 6-phosphate dehydrogenase (G6PD) variant, G6PD Thessaloniki, which was found in the red blood cells of a 70-year-old woman who had idiopathic myelofibrosis, is described. G6PD Thessaloniki had a low Michaelis constant (Km) for G6P (20 microM), high Km for NADP (10.1 microM), normal pH optimum, reduced heat stability, decreased electrophoretic mobility (96-98% of the normal), increased 2-deoxy-G6P and decreased galactose 6-phosphate utilization. Several other enzymatic activities measured in the patient's red blood cells were normal. Studies of red blood cell survival and glucose utilization gave evidence of haemolysis caused by defective glucose utilization by the pentose phosphate pathway. The only son of the patient had normal G6PD in his red blood cells. In an attempt to investigate the origin of G6PD Thessaloniki, heat stability tests of G6PD extracted from the patient's skin have been performed.


Subject(s)
Glucosephosphate Dehydrogenase Deficiency/complications , Glucosephosphate Dehydrogenase/genetics , Primary Myelofibrosis/complications , Aged , Biopsy , Erythrocytes/enzymology , Female , Genetic Variation , Glucosephosphate Dehydrogenase/metabolism , Humans
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