Cell Renewal in the Gill of the Freshwater Mussel, Margaritifera Margaritifera: An Autoradiographic Study using High Specific Activity Tritiated Thymidine

1974 ◽  
Vol 14 (3) ◽  
pp. 561-569
Author(s):  
S. P. TOMASOVIC_ ◽  
M. C. MIX
Keyword(s):  
Specific Activity ◽  
Tritiated Thymidine ◽  
High Specific Activity ◽  
Freshwater Mussel ◽  
Autoradiographic Study ◽  
Cell Renewal ◽  
Margaritifera Margaritifera ◽  
Gill Epithelium ◽  
Stem Type ◽  
Renewal System

High specific activity tritiated thymidine (50.3 Ci/mM and 56 Ci/mM) and autoradiographic techniques were used to study cell renewal in the gill epithelium of the freshwater mussel, Margaritifera margaritifera. The cell renewal system in the gill epithelium of M. inargaritifera appears to consist of a stem-type population in the gill furrow and gill furrow edges which supplies, through division, cells for a maturing, dividing transient transitional population along the proximal gill ridge sides which, in turn, supplies cells to a simple transient, differentiated, functional population on the distal gill ridge sides and tip. Loss of cells from the cell renewal system appears to be through cell death and/or extrusion from the gill ridge tip. No emigration or immigration of labelled nuclei out of, or into, the gill epithelium was observed. The minimum transit time from the dividing transient population to the functional population in the gill ridge tip may be no more than 24 h. We were unable to detect any radiobiological effects or the presence of cytoplasmic labelling due to the use of high specific activities. However, such possibilities cannot be eliminated from consideration in further studies.

scholarly journals Acidic isoferritins and E-type prostaglandins in sources of colony stimulatory factors mask detection of cycling granulocyte-macrophage progenitor cells

Blood ◽  
1982 ◽  
Vol 60 (4) ◽  
pp. 1042-1045 ◽  
Author(s):  
HE Broxmeyer
Keyword(s):  
Progenitor Cells ◽  
Conditioned Medium ◽  
Bone Marrow Cells ◽  
Specific Activity ◽  
Tritiated Thymidine ◽  
High Specific Activity ◽  
Prostaglandin E ◽  
Blood Leukocytes ◽  
Gm Csf ◽  
Feeder Layers

Abstract The effect of granulocyte-macrophage colony stimulatory factors (GM- CSF), acidic isoferritins, and E-type prostaglandins on the detection of the cycle status of human granulocyte-macrophage progenitor cells (CFU-GM) was investigated. Bone marrow cells were pulse-treated with control medium or high specific activity tritiated thymidine [3HTdr) and subsequently plated over feeder layers containing mononuclear blood leukocytes prepared in the absence or presence of anti-acidic isoferritins and/or indomethacin, or plated in the presence of medium conditioned by placental cell or GCT-conditioned media free of acidic isoferritins and prostaglandin-E. The presence of anti-acidic isoferritins and/or indomethacin in the blood leukocyte feeder layers increased the detectable stimulatory capacity of these cells and permitted detection of a larger proportion of marrow CFU-GM in cycle than in control cultures. The cycle status was not influenced by GM-CSF in conditioned medium regardless of the dilution of conditioned medium used to stimulate colony formation. This suggests that GM-CSF, supplied to the cells after treatment with 3HTdr, does not itself influence the detection of CFU-GM in cycle, but using sources of GM-CSF that contain acidic isoferritins or prostaglandin-E will underestimate the actual number of CFU-GM in S-phase.

scholarly journals Acidic isoferritins and E-type prostaglandins in sources of colony stimulatory factors mask detection of cycling granulocyte-macrophage progenitor cells

Blood ◽  
1982 ◽  
Vol 60 (4) ◽  
pp. 1042-1045
Author(s):  
HE Broxmeyer
Keyword(s):  
Progenitor Cells ◽  
Conditioned Medium ◽  
Bone Marrow Cells ◽  
Specific Activity ◽  
Tritiated Thymidine ◽  
High Specific Activity ◽  
Prostaglandin E ◽  
Blood Leukocytes ◽  
Gm Csf ◽  
Feeder Layers

The effect of granulocyte-macrophage colony stimulatory factors (GM- CSF), acidic isoferritins, and E-type prostaglandins on the detection of the cycle status of human granulocyte-macrophage progenitor cells (CFU-GM) was investigated. Bone marrow cells were pulse-treated with control medium or high specific activity tritiated thymidine [3HTdr) and subsequently plated over feeder layers containing mononuclear blood leukocytes prepared in the absence or presence of anti-acidic isoferritins and/or indomethacin, or plated in the presence of medium conditioned by placental cell or GCT-conditioned media free of acidic isoferritins and prostaglandin-E. The presence of anti-acidic isoferritins and/or indomethacin in the blood leukocyte feeder layers increased the detectable stimulatory capacity of these cells and permitted detection of a larger proportion of marrow CFU-GM in cycle than in control cultures. The cycle status was not influenced by GM-CSF in conditioned medium regardless of the dilution of conditioned medium used to stimulate colony formation. This suggests that GM-CSF, supplied to the cells after treatment with 3HTdr, does not itself influence the detection of CFU-GM in cycle, but using sources of GM-CSF that contain acidic isoferritins or prostaglandin-E will underestimate the actual number of CFU-GM in S-phase.

An Important Role for CD1d and NKT Cells in the Suppression of Hematopoiesis in Mice Induced by Infection with Cytomegalovirus.

Blood ◽  
2005 ◽  
Vol 106 (11) ◽  
pp. 574-574
Author(s):  
Hal E. Broxmeyer ◽  
Alexander Dent ◽  
Scott Cooper ◽  
Giao Hangoc ◽  
Gourapura J. Renukaradhya ◽  
...  
Keyword(s):  
Stem Cell ◽  
Stem Cell Transplantation ◽  
Cell Transplantation ◽  
Specific Activity ◽  
Tritiated Thymidine ◽  
High Specific Activity ◽  
Nkt Cells ◽  
Normal Numbers ◽  
Mcmv Infection

Abstract Cytomegalovirus (CMV) is a serious problem in the context of immunocompromised hosts after conditioning for stem cell transplantation. Infection with CMV impacts hematopoiesis, and inhibits colony formation by myeloid progenitor cells (MPC) in vitro and myelopoiesis in vivo. It is not clear how these effects are mediated. Murine (M)CMV has been used as a model for the study of viral pathogenesis and persistent infections. Little is known how CD1d or Natural Killer T (NKT) cells influence effects of CMV infections on hematopoiesis. We hypothesized that CD1d and NKT cells may play a protective role in this effect. We first assessed a role for CD1d on hematopoiesis and found that absolute numbers of MPC (CFU-GM, BFU-E, CFU-GEMM) in marrow and spleen of CD1d −/− mice were significantly higher than in control mice, an observation reproducible in CD1d −/− mice on either a C57Bl/6 or Balb/c background, suggesting that the effects were not due to mouse strain differences. This increased number of MPC was due to increased proliferation of MPC in marrow and spleen since the percentage of MPC in S phase of the cell cycle in CD1d −/− mice, as determined by a high specific activity tritiated thymidine kill assay, was at least two fold higher than in control (+/+) mice. CD1d −/− mice are deficient in NKT cells. We also used Jα18 −/− (C57Bl/6 and Balb/c) mice, which are deficient in NKT cells but express normal cell surface levels of CD1d expression, to demonstrate that the enhanced hematopoiesis in CD1d −/− mice was not a reflection of NKT cell effects; Jα18 −/− mice had normal numbers and cycling status of MPC in marrow and spleen. We then assessed the effects of MCMV (5 x 104 plaque forming units per mouse) on absolute numbers and cycling of MPC in marrow and spleen of +/+, CD1d −/−, and Jα18 −/− mice. Mice were evaluated 4 days post MCMV infection when viral titers are high. While MCMV had some suppressive effects on MPC numbers and cycling of MPC in +/+ C57Bl/6 and Balb/c mice, this suppression was much more pronounced in CD1d −/− and Jα18 −/− mice, with the most potent MCMV effects manifested on these −/− mice on a Balb/c background strain, suggesting that lack of CD1d and/or NKT cells are involved and likely protective in these suppressive viral effects on hematopoiesis. In order to confirm that NKT cells were responsible for this MCMV-induced decrease in hematopoiesis, we utilized Jα18 −/− mice on a Balb/c background to evaluate effects of adding back to these mice (which don’t contain NKT cells) purified Vα 14 Jα18 T cell receptor positive cells isolated from murine liver using CD1d dimers loaded with αGalCer. Mice were given these NKT cells at 2.5 x 105 cells i.v./mouse and immediately after injected with MCMV i.p. The NKT cells blocked MCMV-induced suppression of absolute numbers and cycling of marrow and spleen CFU-GM, BFU-E, and CFU-GEMM, demonstrating that NKT cells play a role in and can block MCMV effects on murine hematopoiesis. This information may thus be relevant to treatment of CMV infections during stem cell transplantation.

Synthesis of macromolecules by the epithelial surfaces ofSchistosoma mansoni: an autoradiographic study

Parasitology ◽  
1979 ◽  
Vol 78 (3) ◽  
pp. 295-310 ◽  
Author(s):  
R. A. Wilson ◽  
P. E. Barnes
Keyword(s):  
Half Life ◽  
Specific Activity ◽  
High Specific Activity ◽  
Autoradiographic Study ◽  
Secretory Protein ◽  
Membrane Turnover ◽  
Electron Microscope Autoradiography ◽  
Glycoprotein Synthesis ◽  
Gut Epithelium ◽  
Rapid Mass

SUMMARYThe use of tritiated leucine as a marker for protein synthesis and of tritiated glucosamine as a marker for polysaccharide/glycoprotein synthesis, is described. Adult worms were pulse-labelled by incubation in medium containing the substrate. Labelled worms were then incubated in chase medium, without labelled substrate, for varying lengths of time before fixation. The distribution of label which had been incorporated into macromolecules in the worm tissues, was examined by light and electron microscope autoradiography. It was estimated that the tegument and tegument cell bodies were the source of 67–80%, and the gut epithelium of 20–33%, of exportable leucine-containing protein. Conversely, the gut epithelium was the source of 72%, and the tegument cells 28%, of exportable glucosamine-containing polysaccharide. The specific activity of labelled protein reached a peak in the tegument cytoplasm after 1.5 h of chase incubation. Half of the labelled protein was secreted into the worm's environment by 3 h of chase incubation. The half-life of secretory protein in gut cells appears to be around 2 h. Labelled protein disappears from the gut lumen relatively rapidly but labelled polysaceharide remains in the lumen at high specific activity for at least 24 h. The major carbohydrate labelled may be the glycocalyx on the luminal surface of the gut epithelial cells. The results suggest that the bulk of worm secretions have a rapid turnover with a half-life of a few hours. Against this background of rapid mass secretion a slower process of membrane turnover would be difficult to detect and quantitatively small.

Effects of Heparin Oligosaccharides with High Affinity for Antithrombin III in Experimental Venous Thrombosis

1982 ◽  
Vol 47 (03) ◽  
pp. 244-248 ◽  
Author(s):  
D P Thomas ◽  
Rosemary E Merton ◽  
T W Barrowcliffe ◽  
L Thunberg ◽  
U Lindahl
Keyword(s):  
Antithrombin Iii ◽  
Specific Activity ◽  
High Specific Activity ◽  
Factor Xa ◽  
Blood Levels ◽  
Thrombin Time ◽  
High Affinity ◽  
Very High

SummaryThe in vitro and in vivo characteristics of two oligosaccharide heparin fragments have been compared to those of unfractionated mucosal heparin. A decasaccharide fragment had essentially no activity by APTT or calcium thrombin time assays in vitro, but possessed very high specific activity by anti-Factor Xa assays. When injected into rabbits at doses of up to 80 ¼g/kg, this fragment was relatively ineffective in impairing stasis thrombosis despite producing high blood levels by anti-Xa assays. A 16-18 monosaccharide fragment had even higher specific activity (almost 2000 iu/mg) by chromogenic substrate anti-Xa assay, with minimal activity by APTT. When injected in vivo, this fragment gave low blood levels by APTT, very high anti-Xa levels, and was more effective in preventing thrombosis than the decasaccharide fragment. However, in comparison with unfractionated heparin, the 16-18 monosaccharide fragment was only partially effective in preventing thrombosis, despite producing much higher blood levels by anti-Xa assays.It is concluded that the high-affinity binding of a heparin fragment to antithrombin III does not by itself impair venous thrombogenesis, and that the anti-Factor Xa activity of heparin is only a partial expression of its therapeutic potential.

Autoprothrombin C Activity from Prothrombin with Snake Venom or Trypsin

1962 ◽  
Vol 08 (03) ◽  
pp. 425-433 ◽  
Author(s):  
Ewa Marciniak ◽  
Edmond R Cole ◽  
Walter H Seegers
Keyword(s):  
Snake Venom ◽  
Thrombolytic Agent ◽  
Sodium Citrate ◽  
Specific Activity ◽  
High Specific Activity ◽  
Citrate Solution ◽  
Clotting Factors ◽  
Activation Products ◽  
Russell’S Viper ◽  
Autoprothrombin C

SummarySuitable conditions were found for the generation of autoprothrombin C from purified prothrombin with the use of Russell’s viper venom or trypsin. DEAE chromatographed prothrombin is structurally altered and has never been found to yield autoprothrombin C and also did not yield it when Russell’s viper venom or trypsin were used. Autoprothrombin C is derived from prothrombin with tissue extract thromboplastin, but not in large amounts with the intrinsic clotting factors. With the latter thrombin and autoprothrombin III are the chief activation products. Autoprothrombin III concentrates were prepared from serum and upon activation with 25% sodium citrate solution or with Russell’s viper venom large amounts of autoprothrombin C were obtained, and this was of high specific activity. Theoretically trypsin is not a thrombolytic agent, but on the contrary should lead to intravascular clotting.

Progestation

1967 ◽  
Vol 56 (3_Suppla) ◽  
pp. S7-S45 ◽  
Keyword(s):  
Tritiated Thymidine ◽  
Succinic Dehydrogenase ◽  
Glandular Epithelium ◽  
Synthetic Activity ◽  
Cell Renewal ◽  
Pulse Labelling ◽  
Uterine Receptivity ◽  
Alkaline Phosphatases ◽  
Monocytic Cells ◽  
Acid And Alkaline Phosphatases

ABSTRACT Autoradiographic, enzymic and histologic studies on uteri of pregnant rats were carried out to follow the endometrial modifications which take place during progestation (days L0 – L4) and culminate in the state of uterine receptivity essential for ovum-implantation. Pulse labelling with tritiated thymidine (radioactive DNA precursor) on L0, L1 and L2 revealed a sequence of cell renewal in luminal and glandular epithelium and endometrial stroma. On L3 and L4 stromal cells showed extensive incorporation of tritiated thymidine. This synthetic activity was associated with endometrial preparation for decidualization and was evoked at least in part, by the surge of oestrogen on L3. All layers of the uterine wall were heavily infiltrated on L0 and resembled the site of an acute inflammatory reaction. Subsequently, polymorphonuclear infiltration diminished and monocytic cells predominated. On L3 a spatial arrangement was observed: eosinophiles were concentrated in the basal endometrium and monocytic cells in the subepithelial stroma. A comparison was made between such a shift in migratory cells in the uterus and similar phenomena which occur in inflammatory and immune reactions. Activities of acid and alkaline phosphatases, of ATP-ase and succinic dehydrogenase were low on L0 and L1 during the periods of infiltration, degeneration and regeneration of luminal and glandular epithelium. Enzymic activities increased on the following days, (L3 and L4). Vascular dilation and engorgement and endometrial oedema were observed near the blastocysts on L4. Most blastocysts incorporated tritiated thymidine after 14.00 h on L4, but some showed uptake before loss of the zona which occurs usually between 14.00 and 16.00 h; therefore, it was assumed that the permeability of the zona increases prior to being shed. Activities of succinic dehydrogenase and acid and alkaline phosphatases were demonstrable in blastocysts on L4 while they were still »free« in the uterine lumen.

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