Sinusoidal Cells in Bone Marrow Take Up BSA-Au Conjugates in the Presence of an Artificial Blood Substitute

1985 ◽  
Vol 43 ◽  
pp. 700-701
Author(s):  
J.S. Geoffroy ◽  
R.P. Becker
Keyword(s):  
Bone Marrow ◽  
Los Angeles ◽  
Iliac Artery ◽  
Blood Substitute ◽  
Sprague Dawley ◽  
Coated Pits ◽  
Sinusoidal Cells ◽  
Artificial Blood ◽  
Left Common Iliac Artery

The pattern of BSA-Au uptake in vivo by endothelial cells of the venous sinuses (sinusoidal cells) of rat bone marrow has been described previously. BSA-Au conjugates are taken up exclusively in coated pits and vesicles, enter and pass through an “endosomal” compartment comprised of smooth-membraned tubules and vacuoles and cup-like bodies, and subsequently reside in multivesicular and dense bodies. The process is very rapid, with BSA-Au reaching secondary lysosmes one minute after presentation. (Figure 1)In further investigations of this process an isolated limb perfusion method using an artificial blood substitute, Oxypherol-ET (O-ET; Alpha Therapeutics, Los Angeles, CA) was developed. Under nembutal anesthesia, male Sprague-Dawley rats were laparotomized. The left common iliac artery and vein were ligated and the right iliac artery was cannulated via the aorta with a small vein catheter. Pump tubing, preprimed with oxygenated 0-ET at 37°C, was connected to the cannula.

Abstract 2838: Bone Marrow Mesenchymal Stem Cells Differentiated into Beating Cardiomyocytes In Vivo and Improved Myocardial Function

Circulation ◽  
2007 ◽  
Vol 116 (suppl_16) ◽  
Author(s):  
Tong Wang ◽  
Wanchun Tang ◽  
Shijie Sun ◽  
Min-shan Tsai ◽  
Max Harry Weil
Keyword(s):  
Stem Cells ◽  
Bone Marrow ◽  
Mesenchymal Stem Cells ◽  
Myocardial Function ◽  
Phosphate Buffer Solution ◽  
Sprague Dawley ◽  
Buffer Solution ◽  
Marrow Mesenchymal Stem Cells ◽  
And Control

Background: In settings of heart failure, infusion of bone marrow mesenchymal stem cells (MSCs) improves myocardial function both in experimental and clinical studies. The mechanism by which MSCs improve myocardial function remains unknown. Hypothesis: MSCs may differentiate into beating myocytes in vivo. The contractility of these cells is comparable with those of myocytes. Methods: A thoracotomy was performed in 10 male Sprague-Dawley rats, weighing 350 – 450g. Myocardial infarction was induced by ligation of the left anterior descending artery (LAD). One week later, animals were randomized to receive 5×10 6 MSCs marked with PKH26 in phosphate buffer solution (PBS) or as a PBS bolus injection into local infarcted myocardium. Six weeks after the MSCs or PBS injection, the hearts were harvested and digested with collagease type II and single cardiomyocytes were obtained. PKH26 labeled myocytes differentiating from MSCs were observed with a microscope Olympus I×71. The contractility of labeled and unlabeled beating cells in MSCs-treated animals was compared. The contractility of unlabeled myocytes was compared between MSCs-treated and control groups. Result: The beating fluorescent labeled myocytes can be found in MSCs-treated animals [(1.2±0.4) ×10 6 ] and contractility of these cells were the same as that of unlabeled beating myocytes (Table 1 ). The contractility of unlabeled myocytes, however, was significantly better in MSCs-treated animals. Conclusion: MSCs could differentiate into the beating myocytes. However, this may not be the sole mechanism of improved myocardial function. Table 1 Cells contractility (%)

scholarly journals Glucagon receptors in endothelial and Kupffer cells of mouse liver.

1988 ◽  
Vol 36 (9) ◽  
pp. 1081-1089 ◽  
Author(s):  
J Watanabe ◽  
K Kanai ◽  
S Kanamura
Keyword(s):  
Endothelial Cells ◽  
Plasma Membrane ◽  
Kupffer Cells ◽  
Mouse Liver ◽  
Intracellular Transport ◽  
Coated Pits ◽  
Sinusoidal Cells ◽  
Nonparenchymal Cells ◽  
Glucagon Receptors

To determine whether hepatic sinusoidal cells contain glucagon receptors and, if so, to study the significance of the receptors in the cells, binding of [125I]-glucagon to nonparenchymal cells (mainly endothelial cells and Kupffer cells) isolated from mouse liver was examined by quantitative autoradiography and biochemical methods. Furthermore, the pathway of intracellular transport of colloidal gold-labeled glucagon (AuG) was examined in vivo. Autoradiographic and biochemical results demonstrated many glucagon receptors in both endothelial cells and Kupffer cells, and more receptors being present in endothelial cells than in Kupffer cells. In vivo, endothelial cells internalized AuG particles into coated vesicles via coated pits and transported the particles to endosomes, lysosomes, and abluminal plasma membrane. Therefore, receptor-mediated transcytosis of AuG occurs in endothelial cells. The number of particles present on the abluminal plasma membrane was constant if the amount of injected AuG increased. Therefore, the magnitude of receptor-mediated transcytosis of AuG appears to be regulated by endothelial cells. Kupffer cells internalized the ligand into cytoplasmic tubular structures via plasma membrane invaginations and transported the ligand exclusively to endosomes and lysosomes, suggesting that the ligand is degraded by Kupffer cells.

scholarly journals A Novel Strategy to Enhance Microfracture Treatment With Stromal Cell-Derived Factor-1 in a Rat Model

2021 ◽  
Vol 8 ◽  
Author(s):  
Taylor Mustapich ◽  
John Schwartz ◽  
Pablo Palacios ◽  
Haixiang Liang ◽  
Nicholas Sgaglione ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Cartilage Repair ◽  
Osteochondral Defect ◽  
Control Group ◽  
Sprague Dawley ◽  
Sprague Dawley Rats ◽  
Stromal Cell Derived Factor ◽  
Empty Control

BackgroundMicrofracture is one of the most widely used techniques for the repair of articular cartilage. However, microfracture often results in filling of the chondral defect with fibrocartilage, which exhibits poor durability and sub-optimal mechanical properties. Stromal cell-derived factor-1 (SDF-1) is a potent chemoattractant for mesenchymal stem cells (MSCs) and is expressed at high levels in bone marrow adjacent to developing cartilage during endochondral bone formation. Integrating SDF-1 into an implantable collagen scaffold may provide a chondro-conductive and chondro-inductive milieu via chemotaxis of MSCs and promotion of chondrogenic differentiation, facilitating more robust hyaline cartilage formation following microfracture.ObjectiveThis work aimed to confirm the chemoattractive properties of SDF-1 in vitro and develop a one-step method for incorporating SDF-1 in vivo to enhance cartilage repair using a rat osteochondral defect model.MethodsBone marrow-derived MSCs (BMSCs) were harvested from the femurs of Sprague–Dawley rats and cultured in low-glucose Dulbecco’s modified Eagle’s medium containing 10% fetal bovine serum, with the medium changed every 3 days. Passage 1 MSCs were analyzed by flow cytometry with an S3 Cell Sorter (Bio-Rad). In vitro cell migration assays were performed on MSCs by labeling cells with carboxyfluorescein diacetate, succinimidyl ester (CFDA-SE; Bio-Rad). For the microfracture model, a 1.6-mm-diameter osteochondral defect was created in the femoral trochleae of 20 Sprague–Dawley rats bilaterally until bone marrow spillage was seen under saline irrigation. One knee was chosen at random to receive implantation of the scaffold, and the contralateral knee was left unfilled as an empty control. Type I collagen scaffolds (Kensey Nash) were coated with either gelatin only or gelatin and SDF-1 using a dip coating process. The rats received implantation of either a gelatin-only scaffold (N = 10) or gelatin-and-SDF-1 scaffold (N = 10) at the site of the microfracture. Femurs were collected for histological analyses at 4- and 8-week time points post-operatively, and sections were stained with Safranin O/Fast Green. The samples were graded blindly by two observers using the Modified O’Driscoll score, a validated scoring system for chondral repair. A minimum of 10 separate grading scores were made per sample and averaged. Quantitative comparisons of cell migration in vitro were performed with one-way ANOVA. Cartilage repair in vivo was also compared among groups with one-way ANOVA, and the results were presented as mean ± standard deviation, with P-values < 0.05 considered as statistically significant.ResultsMSC migration showed a dose–response relationship with SDF-1, with an optimal dosage for chemotaxis between 10 and 100 ng/ml. After scaffold implantation, the SDF-1-treated group demonstrated complete filling of the cartilage defect with mature cartilage tissue, exhibiting strong proteoglycan content, smooth borders, and good incorporation into marginal cartilage. Modified O’Driscoll scores after 8 weeks showed a significant improvement of cartilage repair in the SDF-1 group relative to the empty control group (P < 0.01), with a trend toward improvement when compared with the gelatin-only-scaffold group (P < 0.1). No significant differences in scores were found between the empty defect group and gelatin-only group.ConclusionIn this study, we demonstrated a simple method for improving the quality of cartilage defect repair in a rat model of microfracture. We confirmed the chemotactic properties of SDF-1 on rat MSCs and found an optimized dosage range for chemotaxis between 10 and 100 ng/ml. Furthermore, we demonstrated a strategy to incorporate SDF-1 into gelatin–collagen I scaffolds in vivo at the site of an osteochondral defect. SDF-1-treated defects displayed robust hyaline cartilage resurfacing of the defect with minimal fibrous tissue, in contrast to the empty control group. The results of the in vitro and in vivo studies together suggest that SDF-1-mediated signaling may significantly improve the quality of cartilage regeneration in an osteochondral defect.

Serum Antibody Titers in Rats Receiving Repeated Small Subcutaneous Injections of Hemoglobin or Polyhemoglobin: A Preliminary Report

1986 ◽  
Vol 9 (3) ◽  
pp. 179-182 ◽  
Author(s):  
C.M. Hertzman ◽  
P.E. Keipert ◽  
T.M.S. Chang
Keyword(s):  
Preliminary Report ◽  
Serum Antibody ◽  
Blood Substitute ◽  
Cross Linking ◽  
Sprague Dawley ◽  
Subcutaneous Injections ◽  
Artificial Blood ◽  
Double Antibody ◽  
Sprague Dawley Rats ◽  
Antibody Titers

Cross-linking hemoglobin (Hb) into Polyhemoglobin (PolyHb) for use as an artificial blood substitute may affect its antigenicity. To investigate this, male Sprague-Dawley rats are immunized with one of the following: rat stroma-free Hb (rSFHb), rat PolyHb (rPolyHb), human stroma-free Hb (hSFHb), and human PolyHb (hPolyHb). Antibody titers are quantified using a double antibody radioimmunoassay. These results show that more antibodies are produced to hPolyHb than to hSFHb, whereas rSFHB and rPolyHb are relatively non-antigenic. Thus, under homologous conditions, cross-linking hemoglobin does not significantly increase its antigenicity, whereas under heterologous conditions the molecule becomes more antigenic.

Application of Backscattered Electron Imaging to the Study of Scavenger Receptor-Mediated Endocytosis by Sinusoidal Cells in Bone Marrow

1985 ◽  
Vol 43 ◽  
pp. 542-545
Author(s):  
R.P. Becker ◽  
J.S. Geoffroy
Keyword(s):  
Bone Marrow ◽  
Endothelial Cells ◽  
Coated Pits ◽  
Thin Sections ◽  
Backscattered Electron Imaging ◽  
Sinusoidal Cells ◽  
Dense Bodies ◽  
Sinusoidal Cell ◽  
Backscattered Electron ◽  
Electron Imaging

The endothelial cells lining the postcapillary venous sinuses (sinusoids) in bone marrow take up colloidal gold-bovine serum albumin (BSA-Au) conjugates by means of a pathway involving coated pits and vesicles. Endocytosis of BSA- Au by these sinusoidal endothelial cells (sinusoidal cells) is rapid. Within one minute of pulse presentation (5 sec; intraaortic injection) with BSA-Au the probe is internalized and processed through pleomorphic endosomes to dense bodies known to be secondary lysosomes. By this time, 17% of the sinusoidal cell related BSA-Au is associated with the surface, while 83% is internalized, of which 2% is present in lysosomes. By four minutes, less than 8% of the observed BSA-Au is not internalized, the bulk being present predominantly in large pleomorphic vacuoles and dense bodies.That the endocytic process involves coated pits and vesicles prompts the suggestion that it may be receptor mediated. In order to investigate this possibility, biochemical and morphological studies were performed to determine the specificity and saturability of the putative receptor. Morphological analysis of TEM thin sections was aided by viewing large areas of the luminal sinusoidal cell surface in secondary electron (SEI) and backscattered electron imaging (BEI) modes of the scanning electron microscope.

scholarly journals Uptake of chemically modified low density lipoproteins in vivo is mediated by specific endothelial cells.

1985 ◽  
Vol 100 (1) ◽  
pp. 103-117 ◽  
Author(s):  
R E Pitas ◽  
J Boyles ◽  
R W Mahley ◽  
D M Bissell
Keyword(s):  
Bone Marrow ◽  
Endothelial Cells ◽  
Kupffer Cells ◽  
Low Density Lipoproteins ◽  
Low Density ◽  
Coated Pits ◽  
Sinusoidal Endothelial Cells ◽  
Modified Lipoproteins

Acetoacetylated (AcAc) and acetylated (Ac) low density lipoproteins (LDL) are rapidly cleared from the plasma (t1/2 approximately equal to 1 min). Because macrophages, Kupffer cells, and to a lesser extent, endothelial cells metabolize these modified lipoproteins in vitro, it was of interest to determine whether endothelial cells or macrophages could be responsible for the in vivo uptake of these lipoproteins. As previously reported, the liver is the predominant site of the uptake of AcAc LDL; however, we have found that the spleen, bone marrow, adrenal, and ovary also participate in this rapid clearance. A histological examination of tissue sections, undertaken after the administration of AcAc LDL or Ac LDL (labeled with either 125I or a fluorescent probe) to rats, dogs, or guinea pigs, was used to identify the specific cells binding and internalizing these lipoproteins in vivo. With both techniques, the sinusoidal endothelial cells of the liver, spleen, bone marrow, and adrenal were labeled. Less labeling was noted in the ovarian endothelia. Uptake of AcAc LDL by endothelial cells of the liver, spleen, and bone marrow was confirmed by transmission electron microscopy. These data suggest uptake through coated pits. Uptake of AcAc LDL was not observed in the endothelia of arteries (including the coronaries and aorta), veins, or capillaries of the heart, testes, kidney, brain, adipose tissue, and duodenum. Kupffer cells accounted for a maximum of 14% of the 125I-labeled AcAc LDL taken up by the liver. Isolated sinusoidal endothelial cells from the rat liver displayed saturable, high affinity binding of AcAc LDL (Kd = 2.5 X 10(-9) M at 4 degrees C), and were shown to degrade AcAc LDL 10 times more effectively than aortic endothelial cells. These data indicate that specific sinusoidal endothelial cells, not the macrophages of the reticuloendothelial system, are primarily responsible for the removal of these modified lipoproteins from the circulation in vivo.

Complement activation by artificial blood substitute Fluosol: in vitro and in vivo studies

Transfusion ◽  
1991 ◽  
Vol 31 (7) ◽  
pp. 642-647 ◽  
Author(s):  
F Hong ◽  
KA Shastri ◽  
GL Logue ◽  
MB Spaulding
Keyword(s):  
Complement Activation ◽  
Blood Substitute ◽  
In Vivo Studies ◽  
Artificial Blood

Differential Modulation of Erythrogenic Effects of EPO by Prolonged Administration of Glucocorticoids.

Blood ◽  
2007 ◽  
Vol 110 (11) ◽  
pp. 1733-1733
Author(s):  
Zili He ◽  
Maged Khalil ◽  
Srinivas Kodali ◽  
Seema Naik ◽  
Chenthilmuragan Rathnasabapathy ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Body Weight ◽  
Combined Treatment ◽  
Control Treatment ◽  
Prolonged Treatment ◽  
Sprague Dawley ◽  
Research Committee ◽  
Interesting Phenomenon ◽  
In Vivo Effects

Abstract Glucocorticoids have either stimulatory or inhibitory effects on erythropoesis depending upon the timing and the dosage of their administration. We previously reported cases of enhanced hematopoetic recovery in response to erythropoietin (Epo; Procrit) in patients receiving prolonged treatment of glucocortcoids. To examine the differential roles of glucocorticoids on erythropoiesis in chronic settings, we use a murine model in current study and evaluate erythropoietic responses to Epo for rats receiving higher (loading) or lower (maintenance) dosages of dexamethasone(Dex) for a prolonged period of time. Commercially-obtained adult Sprague-Dawley rats were assigned randomly to DEX, EPO, DEX+EPO, or control groups, and maintained at conditions approved by the institutional Animal Care and Research Committee. Rats in the EPO or DEX+EPO groups received subcutaneous injection of Epo at 70 units/100 grams body weight, once a week, for five week. The animals in the DEX or DEX+EPO group were both divided into two subgroups receiving injection of Dex at either higher doses of 0.4mg/350 grams body weight, or lower doses of 0.02 mg/350 grams body weight, three times a week, for five weeks. The animals were sacrificed at the end of study and peripheral blood and bone marrow were used to evaluate levels of erythropoiesis. Weekly administration of Epo (70 units/100 grams body weight) for five weeks produced enhanced erythropoiesis in the EPO group, resulting in an increase of 10.6% in RBC, and 15.3% increase in hemoglobin (Hb), compared to control. Treatment of rats with higher dosage (0.4 mg/350 g, three times a week for five weeks) of dexamethasone increased RBC and Hb by 3% and 2%, respectively, when compared with controls. Combined treatment of Epo and dexamethasone at the higher dosage enhanced the erythropoiesis, and increased RBC and Hb by 20% and 23%, respectively. In contrast, treatment of rats with a lower maintenance dosage of 0.02 mg/350 g body weight, three times a week for five weeks, peripheral RBC and Hb levels were dropped by 7% and 6%, respectively. Combination of Epo and the lower dosage of dexamethasone could only generate an increase in RBC and Hb of 10% each, displaying suppressing effect of dexamethasone at lower dosage. Bone marrow biopsy revealed hypocellularity in all groups using dexamethasone. Marrow iron staining was performed and ruled out any iron deficiency in all groups. These results suggest that glucocorticoids modulate erythropoisis in two ways depending on concentrations, enhancing erythropoiesis greatly at loading dosage while suppressing it at lower maintenance doses. Our data, together with our clinical observations, present an interesting phenomenon of cross modulation of the two widely used medications, Epo and glucocorticoids. It certainly warrants further investigation of involving pathways at molecular levels. In Vivo Effects of Dexamethasone on Epo stimulated erythropoiesis In Vivo Effects of Dexamethasone on Epo stimulated erythropoiesis

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