scholarly journals Granulocyte/macrophage-, megakaryocyte-, eosinophil- and erythroid-colony-stimulating factors produced by mouse spleen cells

1980 ◽  
Vol 185 (2) ◽  
pp. 301-314 ◽  
Author(s):  
Antony W. Burgess ◽  
Donald Metcalf ◽  
Sue H. M. Russell ◽  
Nicos A. Nicola

The formation of mature haemopoietic cells is controlled by hormones that specifically stimulate the progenitor cells of the granulocyte/macrophage, eosinophil, megakaryocyte and erythroid pathways. PWMSC medium (pokeweed-mitogen-stimulated spleen-cell-conditioned medium) is known to contain the biological activities that control the clonal proliferation of these four progenitor cells in vitro in semi-solid agar cultures. In this study the molecular properties of these biological activities were characterized, and all four colony-stimulating factors appear to be associated with glycoproteins. These factors were precipitated between 50 and 80%-satd. (NH4)2SO4 and could be concentrated by ultrafiltration over a 10000-mol.wt.-cut-off hollow-fibre membrane. Megakaryocyte- and erythroid-colony-stimulating factors were lost when the conditioned medium was dialysed at low ionic strength (<0.03m). Neither asialo- nor sialo-erythropoietin was detectable in concentrated PWMSC medium or in the fractions purified from it by gel filtration on Sephadex G-150. The factors bound to concanavalin A–Sepharose were eluted with α-methyl-d-glucopyranoside (0.10m). Analysis by gel filtration on Sephadex G-150 indicated that the apparent molecular-weight distributions of all colony-stimulating factors were identical (37000). Treatment with neuraminidase did not alter the biological activities of any of these factors, but when the molecular weights were analysed, after neuraminidase treatment, on Sepharose CL-6B in the presence of guanidine hydrochloride (6m) all were eluted with a mol.wt. of 24000. Although the apparent molecular weights of the different factors were identical, charge differences were detectable by isoelectric focusing on thin-layer granulated gels. There appeared to be considerable charge heterogeneity associated with each factor, as all were focused over 2–4 pH units. The maximum activity of the granulocyte/macrophage-colony-stimulating factor on isoelectric focusing was at pH4.8, whereas the maximum activity for the eosinophil-colony-stimulating factor was at pH5.8. The erythroid- and megakaryocyte-colony-stimulating activities were detected in the pH ranges 4.8–5.8 and 4.6–7.1 respectively. Chromatographic differences between the granulocyte/macrophage- and eosinophil-colony-stimulating factors were also detected by hydrophobic chromatography at low ionic strength (0.15m-NaCl) on Cibacron Blue–Sepharose and at high ionic strength [2m-(NH4)2SO4] on phenyl-Sepharose. Eosinophil-colony-stimulating factor bound more strongly than the other factors to both matrices. The megakaryocyte- and erythroid-colony-stimulating activities were always associated with those for granulocytes/macrophages and eosinophils. Preparations highly enriched for eosinophil-colony-stimulating factor were also obtained by DEAE-cellulose chromatography. An overall purification of 100-fold for all of the factors was achieved with the present techniques, and, although differences were observed, only granulocyte/macrophage-stimulating factors and a small proportion of the eosinophil-stimulating factors could be completely separated from the others. Our results are consistent with the existence of separable factors for granulocyte/macrophage and eosinophil stimulation, but the megakaryocyte- and erythroid-stimulating activities were always associated with the granulocyte/macrophage- and eosinophil-stimulating activities. Thus there may be one molecule that is able to stimulate all four colony types or four very similar molecules that are difficult to separate.

1976 ◽  
Vol 155 (1) ◽  
pp. 19-23 ◽  
Author(s):  
K B M Reid ◽  
R R Porter

1. Unreduced human subcomponent C1q was shown by electrophoresis on polyacrylamide gels run in the presence of sodium dodecyl sulphate to be composed of two types of non-covalently linked subunits of apparent mol.wts. 69 000 and 54 000. The ratio of the two subunits was markedly affected by the ionic strength of the applied sample. At a low ionic strength of applied sample, which gave the optimum value for the 54 000-apparent mol.wt. subunit, a ratio of 1.99:1.00 was obtained for the ratio of the 69 000-apparent mol.wt. subunit to the 5400-apparent-mol.wt. subunit. The amount of the 54 000-apparent-mol.wt. subunit detected in the expected position on the gel was found to be inversely proportional to increases in the ionic strength of the applled sample. 2. Human subcomponent C1q on reduction and alkylation, or oxidation, yields equimolar amounts of three chains designated A, B and C [Reid et al. (1972) Biochem. J. 130, 749-763]. The results obtained by Yonemasu & Stroud [(1972) Immunochemistry 9, 545-554], which showed that the 69 000-apparent-mol.wt. subunit was a disulphide-linked dimer of the A and B chains and that the 54 000-apparent-mol.wt. subunit was a disulphide-linked dimer of the C chain, were confirmed. 3. Gel filtration on Sephadex G-200 in 6.0M-guanidinium chloride showed that both types of unreduced subunit were eluted together as a single symmetrical peak of apparent mol.wt. 49 000-50 000 when globular proteins were used as markers. The molecular weights of the oxidized or reduced A, B and C chains have been shown previously to be very similar all being in the range 23 000-24 000 [Reid et al. (1972) Biochem. J. 130, 749-763; Reid (1974) Biochem. J. 141, 189-203]. 4. It is proposed that subcomponent C1q (mol.wt. 410000) is composed of nine non-covalently linked subunits, i.e. six A-B dimers and three C-C dimers. 5. A structure for subcomponent C1q is proposed and is based on the assumption that the collagen-like regions of 78 residues in each of the A, B and C chains are combined to form a triple-helical structure of the same type as is found in collagens.


2021 ◽  
pp. 107815522110386
Author(s):  
Angela Chen ◽  
Vincent H Ha ◽  
Sunita Ghosh ◽  
Carole R Chambers ◽  
Michael B Sawyer

Introduction The metastatic pancreatic adenocarcinoma clinical trial (MPACT) trial established gemcitabine (gem) and nab-paclitaxel (nab) as a standard treatment for pancreatic cancer utilizing granulocyte colony-stimulating factors to manage neutropenia. This was a challenge for jurisdictions that do not use granulocyte colony-stimulating factors in palliative settings. We developed dosage guidelines to dose modify gem and nab without granulocyte colony-stimulating factors. We undertook a retrospective review to determine the efficacy and safety of these dose adjustment guidelines in the real world. Methods A multi-centered, retrospective chart review was performed on pancreatic patients between December 1, 2014, and August 21, 2018. Provincial electronic medical health records were reviewed. Using Log-rank statistics we determined the patient's progression-free survival and overall survival. Results Of 248 patients, 209 met patient selection criteria. Patients were excluded if they were lost to follow-up, on gem alone prior to nab/gem combination therapy or did not receive nab or gem. Patients who received nab/gem as first-line therapy had a median progression-free survival of 6.3 months (95% CI, 5.1–7.4), and median overall survival of 11.1 months (95% CI, 9.5–12.8). Those who received gem/nab in the second line had a median progression-free survival of 4.6 months (95% CI, 2.8–6.5), and median overall survival of 19.3 months (95% CI, 12.6–26.0). Conclusions The patient’s progression-free survival and overall survival taking nab/gem using our dose modification algorithm were equivalent or superior to the MPACT trial's progression-free survival and overall survival. Gem/nab can be given by our dose modification scheme without granulocyte colony-stimulating factor.


2020 ◽  
pp. 107815522091577 ◽  
Author(s):  
Jennifer R Schenfeld ◽  
Corina W Bennett ◽  
Shuling Li ◽  
Lucy J DeCosta ◽  
Renee R Jaramillo ◽  
...  

Purpose Describe temporal changes in use of myelosuppressive chemotherapy, primary prophylactic colony-stimulating factor, and neutropenia-related hospitalization, in commercially insured patients. Methods Using a large commercial administrative database, we identified annual cohorts of adult patients diagnosed with breast or lung cancer, or non-Hodgkin lymphoma and initiating myelosuppressive chemotherapy during 2005–2017. We described yearly changes in proportions of myelosuppressive chemotherapy by febrile neutropenia risk category (high, intermediate, unclassified) and proportion of prophylactic colony-stimulating factor use and unadjusted incidence of neutropenia-related hospitalization in the first cycle of myelosuppressive chemotherapy. Results Annual cohorts included 4383–5888 eligible patients during 2005–2017. The proportion of eligible patients aged ≥ 65 years increased from 26.0% in 2005 to 58.2% in 2017. Myelosuppressive chemotherapy use with regimens with high risk for febrile neutropenia increased from 15.1% in 2005 to 31.0% in 2017; and regimens with intermediate risk for febrile neutropenia decreased from 63.7% to 48.1% in 2017. Prophylactic colony-stimulating factor use increased from 41.6% in 2005 to 54.3% in 2017. Crude incidence of neutropenia-related hospitalization for all cancers increased from 2.0% to 3.1%, with a substantial increase in neutropenia-related hospitalization observed among non-Hodgkin lymphoma patients (2.8% to 8.5%) during 2005–2017. Conclusion Among adult patients with breast and lung cancer, and non-Hodgkin lymphoma receiving myelosuppressive chemotherapy, use of regimens with high risk for febrile neutropenia increased, as did the use of prophylactic colony-stimulating factors after 2005. Incidence of neutropenia-related hospitalization increased slightly, particularly among non-Hodgkin lymphoma patients. Further studies are required to understand this increasing trend of neutropenia-related hospitalization, changing patient-level risk factors, and febrile neutropenia management.


1970 ◽  
Vol 48 (8) ◽  
pp. 944-946 ◽  
Author(s):  
E. Griffiths

The stability, in solutions of low ionic strength, of aminoacyl-tRNA synthetases from the extremely halophilic bacterium Halobacterium cutirubrum was studied as a preliminary to their fractionation. The enzymes differed considerably in their sensitivity to such solutions. Conditions were found where reactivation from the salt-free and inactive state could be achieved. Removal of both K+ and Mg2+ together generally resulted in better stability than the removal of K+ alone. A low temperature (4°) was also important for stability in buffers of low ionic strength. In some cases the L-amino acid substrates afforded protection against inactivation in the salt-free state. Gel filtration in low ionic strength medium was found to work well as a fractionation procedure; a partial purification of phenylalanyl-tRNA synthetase was effected in this way. The use of other conventional protein fractionation procedures is now possible.


1988 ◽  
Vol 252 (3) ◽  
pp. 865-874 ◽  
Author(s):  
R A Harrison

A study was made of hyaluronidase in ram semen. The end-group assay conditions used to determine activity quantitatively were chosen to ensure reliability as well as sensitivity [Gacesa, Savitsky, Dodgson & Olavesen (1981) Anal. Biochem. 118, 76-84]; they led to 1 W.H.O. Standard International Hyaluronidase Unit displaying 0.1263 EC munit (1 EC unit of activity releases 1 mumol equivalent of N-acetylglucosamine end groups/min at 37 degrees C). All the activity in the semen was shown to be sperm-derived, and intact spermatozoa were estimated to contain 1.23 EC units per 10(9) cells. In a low-ionic-strength medium, only some 20% of the hyaluronidase was extractable, although up to 80% of the activity could be extracted as the ionic strength was increased; further addition of detergent extracted the remainder. During purification of the enzyme, it was found that inclusion of poly(vinyl alcohol) in the media stabilized the activity; detergent inclusion also improved the yield, especially during early stages. As a consequence both of reliable quantitative determination and of stabilization, a number of forms of hyaluronidase could be isolated in high yield, by using anion-exchange chromatography, cation-exchange chromatography, affinity chromatography and gel filtration. The existence of all these forms was confirmed by electrophoresis and immunoblotting with the use of a monoclonal anti-(ram hyaluronidase) antibody, and their presence in very freshly prepared sperm extracts was demonstrated. The specific activity of the isolated major hyaluronidase form was 15.0 EC units/mg; this was equivalent to 119,000 W.H.O. units/mg, higher than any other previously reported values.


1972 ◽  
Vol 128 (5) ◽  
pp. 1033-1041 ◽  
Author(s):  
R. S. Mitra ◽  
B. Bartoov ◽  
J. Monahan ◽  
K. B. Freeman

Mitochondrial ribosomal RNA species from mouse L cells, rat liver, rat hepatoma, hamster BHK-21 cells and human KB cells were examined by electrophoresis on polyacrylamide–agarose gels and sedimentation in sucrose density gradients. The SE (electrophoretic mobility) and S values of mitochondrial rRNA of all species were highly dependent on temperature and ionic strength of the medium; the SE values increased and the S values decreased with an increase in temperature at a low ionic strength. At an ionic strength of 0.3 at 23–25°C or an ionic strength of 0.01 at 3–4°C the S and SE values were almost the same being about 16.2–18.0 and 12.3–13.6 for human and mouse mitochondrial rRNA. The molecular weights under these conditions were calculated to be 3.8×105–4.3×105 and 5.9×105–6.8×105, depending on the technique used. At 25°C in buffers of low ionic strength mouse mitochondrial rRNA species had a lower electrophoretic mobility than those of human and hamster. Under these conditions the smaller mitochondrial rRNA species of hamster had a lower electrophoretic mobility than that of human but the larger component had an identical mobility. Mouse and rat mitochondrial rRNA species had identical electrophoretic mobilities. Complex differences between human and mouse mitochondrial rRNA species were observed on sedimentation in sucrose density gradients under various conditions of temperature and ionic strength. Mouse L-cell mitochondrial rRNA was eluted after cytoplasmic rRNA on a column of methylated albumin–kieselguhr.


1966 ◽  
Vol 15 (03/04) ◽  
pp. 501-510 ◽  
Author(s):  
W Berg ◽  
K Korsan-Bengtsen ◽  
J Ygge

SummaryA simple method for preparation of plasminogen-free human and bovine thrombin is described.Crude thrombin was prepared in the usual manner from oxalated plasma by means of adsorption on BaSO4, elution with trisodium citrate and activating the eluate from BaSO4 with tissue thromboplastin.This crude thrombin was purified by means of gel-filtration and chromatography on CM-Sephadex A-50.The gel-filtration was performed on three types of Sephadex, G-75, G-50, and G--25. By means of Sephadex G-75 the thrombin was well separated from the main part of inert protein and this type of Sephadex was used for the purification in large-scale. Separation of thrombin from protein of higher molecular weight was also obtained with Sephadex G-50 but not with Sephadex G-25 indicating a molecular weight of thrombin between 4000 and 10,000.The importance of using an elution buffer of sufficient high ionic strength for gel-filtration is shown. A great deal of the thrombin was adsorbed to the Sephadex if the gel-filtration was performed at a too low ionic strength.The final preparation contained 30,000 NIH units of thrombin per mg tyrosin and no detectable plasminogen.The commercial preparation “Topostasine” was also purified in the same manner, but the plasminogen content in “Topostasine” was high and could not be completely separated from thrombin.


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