Experimental modification of rat pituitary growth hormone cell function during and after spaceflight

Space-flown rats show a number of flight-induced changes in the structure and function of pituitary growth hormone (GH) cells after in vitro postflight testing (W. C. Hymen, R. E. Grindeland, I. Krasnov, I, Victorov, K. Motter, P. Mukherjee, K. Shellenberger, and M. Vasques. J. Appl. Physiol. 73, Suppl.: 151S-157S, 1992). To evaluate the possible effects of microgravity on growth hormone (GH) cells themselves, freshly dispersed rat anterior pituitary gland cells were seeded into vials containing serum +/- microM hydrocortisone (HC) before flight. Five different cell preparations were used: the entire mixed-cell population of various hormone-producing cell types, cells of density < 1.071 g/cm3 (band 1), cells of density > 1.071 g/cm3 (band 2), and cells prepared from either the dorsal or ventral part of the gland. Relative to ground control samples, bioactive GH released from dense cells during flight was reduced in HC-free medium but was increased in HC-containing medium. Band 1 and mixed cells usually showed opposite HC-dependent responses. Release of bioactive GH from ventral flight cells was lower; postflight responses to GH-releasing hormone challenge were reduced, and the cytoplasmic area occupied by GH in the dense cells was greater. Collectively, the data show that the chemistry and cellular makeup of the culture system modifies the response of GH cells to microgravity. As such, these cells offer a system to identify gravisensing mechanisms in secretory cells in future microgravity research.

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Different Degrees of Somatotroph Ablation Compromise Pituitary Growth Hormone Cell Network Structure and Other Pituitary Endocrine Cell Types

Endocrinology ◽

10.1210/en.2009-0539 ◽

2010 ◽

Vol 151 (1) ◽

pp. 234-243 ◽

Cited By ~ 29

Author(s):

Eleanor Waite ◽

Chrystel Lafont ◽

Danielle Carmignac ◽

Norbert Chauvet ◽

Nathalie Coutry ◽

...

Keyword(s):

Growth Hormone ◽

Network Structure ◽

Endocrine Cell ◽

Cell Types ◽

Cell Network ◽

Pituitary Growth Hormone ◽

Growth Hormone Cell

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Formation of Centrioles in Some Endocrine Adenomas

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010011550x ◽

1975 ◽

Vol 33 ◽

pp. 376-377

Author(s):

E. Horvath ◽

K. Kovacs

Keyword(s):

Growth Hormone ◽

Pituitary Adenomas ◽

Osmium Tetroxide ◽

Mitotic Division ◽

Mixed Cell ◽

Pituitary Growth Hormone ◽

Parathyroid Adenomas ◽

Growth Hormone Cell ◽

Formation And Evolution ◽

Insight Into

Centrioles, known to play a fundamental role in mitotic division, are regarded as representing self-replicating organelles. They occur with varying frequency in different normal cells and exhibit uniform appearances showing no signs indicative of duplication such as budding or division. In order to obtain a deeper insight into centriole formation and evolution, cases of parathyroid and pituitary adenomas with a high centriole population were investigated by electron microscopy.The material used for the present study consisted of 4 chief cell adenomas of the parathyroid gland, 7 sparsely granulated pituitary growth hormone cell adenomas and 1 mixed cell pituitary adenoma composed of sparsely granulated growth hormone cells and prolactin cells. These adenomas were selected from a large number of cases (26 parathyroid adenomas and 49 pituitary adenomas). All specimens were obtained by surgery from various patients with hyperparathyroidism or acromegaly. Small pieces of tissue were fixed immediately after removal in 2.5 per cent glutaraldehyde in Sorensen's buffer, postfixed in 1 per cent osmium tetroxide in Millonig's buffer, dehydrated in graded ethanol and embedded in Epon 812.

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Role of the 807 C/T Polymorphism of the α2 Gene in Platelet GP Ia Collagen Receptor Expression and Function

Thrombosis and Haemostasis ◽

10.1055/s-0037-1614605 ◽

1999 ◽

Vol 81 (06) ◽

pp. 951-956 ◽

Cited By ~ 59

Author(s):

J. Corral ◽

R. González-Conejero ◽

J. Rivera ◽

F. Ortuño ◽

P. Aparicio ◽

...

Keyword(s):

Venous Thrombosis ◽

Cell Types ◽

Receptor Expression ◽

Case Control Studies ◽

Platelet Surface ◽

Vitro Analysis ◽

And Function ◽

In Vitro Analysis

SummaryThe variability of the platelet GP Ia/IIa density has been associated with the 807 C/T polymorphism (Phe 224) of the GP Ia gene in American Caucasian population. We have investigated the genotype and allelic frequencies of this polymorphism in Spanish Caucasians. The T allele was found in 35% of the 284 blood donors analyzed. We confirmed in 159 healthy subjects a significant association between the 807 C/T polymorphism and the platelet GP Ia density. The T allele correlated with high number of GP Ia molecules on platelet surface. In addition, we observed a similar association of this polymorphism with the expression of this protein in other blood cell types. The platelet responsiveness to collagen was determined by “in vitro” analysis of the platelet activation and aggregation response. We found no significant differences in these functional platelet parameters according to the 807 C/T genotype. Finally, results from 3 case/control studies involving 302 consecutive patients (101 with coronary heart disease, 104 with cerebrovascular disease and 97 with deep venous thrombosis) determined that the 807 C/T polymorphism of the GP Ia gene does not represent a risk factor for arterial or venous thrombosis.

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Modelling the Human Placental Interface In Vitro—A Review

Micromachines ◽

10.3390/mi12080884 ◽

2021 ◽

Vol 12 (8) ◽

pp. 884

Author(s):

Marta Cherubini ◽

Scott Erickson ◽

Kristina Haase

Keyword(s):

Drug Testing ◽

Cell Types ◽

In Vitro Models ◽

Placental Development ◽

Scientific Challenge ◽

Induced Pluripotent ◽

And Function ◽

And Control

Acting as the primary link between mother and fetus, the placenta is involved in regulating nutrient, oxygen, and waste exchange; thus, healthy placental development is crucial for a successful pregnancy. In line with the increasing demands of the fetus, the placenta evolves throughout pregnancy, making it a particularly difficult organ to study. Research into placental development and dysfunction poses a unique scientific challenge due to ethical constraints and the differences in morphology and function that exist between species. Recently, there have been increased efforts towards generating in vitro models of the human placenta. Advancements in the differentiation of human induced pluripotent stem cells (hiPSCs), microfluidics, and bioprinting have each contributed to the development of new models, which can be designed to closely match physiological in vivo conditions. By including relevant placental cell types and control over the microenvironment, these new in vitro models promise to reveal clues to the pathogenesis of placental dysfunction and facilitate drug testing across the maternal–fetal interface. In this minireview, we aim to highlight current in vitro placental models and their applications in the study of disease and discuss future avenues for these in vitro models.

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Exogenous Growth Hormone Inhibits Bovine but Not Murine Pituitary Growth Hormone Secretion in vitro: Evidence for a Direct Feedback of Growth Hormone on the Pituitary

Neuroendocrinology ◽

10.1159/000125779 ◽

1991 ◽

Vol 53 (6) ◽

pp. 597-600 ◽

Cited By ~ 16

Author(s):

Stephen M. Rosenthal ◽

Bernhard L. Silverman ◽

William B. Wehrenberg

Keyword(s):

Growth Hormone ◽

Hormone Secretion ◽

Growth Hormone Secretion ◽

Pituitary Growth Hormone ◽

Exogenous Growth ◽

Direct Feedback

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Faculty Opinions recommendation of The FGFR4-G388R polymorphism promotes mitochondrial STAT3 serine phosphorylation to facilitate pituitary growth hormone cell tumorigenesis.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.717348022.792703132 ◽

2012 ◽

Author(s):

Günter Stalla ◽

Ulrich Renner

Keyword(s):

Growth Hormone ◽

Serine Phosphorylation ◽

Pituitary Growth Hormone ◽

Growth Hormone Cell

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Administration of cardiac mesenchymal cells modulates innate immunity in the acute phase of myocardial infarction in mice

Scientific Reports ◽

10.1038/s41598-020-71580-z ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Yi Kang ◽

Marjan Nasr ◽

Yiru Guo ◽

Shizuka Uchida ◽

Tyler Weirick ◽

...

Keyword(s):

Myocardial Infarction ◽

Innate Immunity ◽

Mechanism Of Action ◽

Cell Activation ◽

Cell Function ◽

Immune Cell ◽

Mesenchymal Cell ◽

Cell Types

Abstract Although cardiac mesenchymal cell (CMC) therapy mitigates post-infarct cardiac dysfunction, the underlying mechanisms remain unidentified. It is acknowledged that donor cells are neither appreciably retained nor meaningfully contribute to tissue regeneration—suggesting a paracrine-mediated mechanism of action. As the immune system is inextricably linked to wound healing/remodeling in the ischemically injured heart, the reparative actions of CMCs may be attributed to their immunoregulatory properties. The current study evaluated the consequences of CMC administration on post myocardial infarction (MI) immune responses in vivo and paracrine-mediated immune cell function in vitro. CMC administration preferentially elicited the recruitment of cell types associated with innate immunity (e.g., monocytes/macrophages and neutrophils). CMC paracrine signaling assays revealed enhancement in innate immune cell chemoattraction, survival, and phagocytosis, and diminished pro-inflammatory immune cell activation; data that identifies and catalogues fundamental immunomodulatory properties of CMCs, which have broad implications regarding the mechanism of action of CMCs in cardiac repair.

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Polymorphonuclear Leukocytes Prepared by Continuous-Flow Filtration Leukapheresis: Viability and Function

Blood ◽

10.1182/blood.v44.5.707.707 ◽

1974 ◽

Vol 44 (5) ◽

pp. 707-713 ◽

Cited By ~ 23

Author(s):

Michael B. Harris ◽

Isaac Djerassi ◽

Elias Schwartz ◽

Richard K. Root

Keyword(s):

Continuous Flow ◽

Polymorphonuclear Leukocytes ◽

Cell Types ◽

High Yield ◽

Trypan Blue Exclusion ◽

Flow Filtration ◽

And Function ◽

Combating Infection

Abstract Preparation of granulocytes for transfusion in high yield and relatively free of contamination by other cell types has been made possible by the technique of continuous-flow filtration leukapheresis (CFFL). Since previous work suggested that granulocytes collected in this manner may have impaired viability and function, a detailed study of the bactericidal, metabolic, and chemotactic properties of such cells was performed and compared to control cells obtained from the same donors prior to CFFL. The granulocyte percentage of the cell suspensions obtained by CFFL averaged 94.5% ± 1.5% compared to 82.5% ± 1.8% for the controls (p < 0.001) with viability of the PMNs determined by trypan blue exclusion being 97.5% ± 0.9% and 98.2% ± 0.5%, respectively. The phogocytic, metabolic (14C-I-glucose oxidation and protein iodination) and chemotactic properties of both cell types were equivalent in suspensions equalized for granulocyte content. These findings indicate that CFFL technique employed does not impair granulocyte viability or function in vitro. Studies of the in vivo survival and function of CFFL granulocytes are necessary to evaluate their efficacy in combating infection in severely leukopenic patients.

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In vitro differentiation of CD34+ hematopoietic progenitor cells toward distinct dendritic cell subsets of the birbeck granule and MIIC- positive Langerhans cell and the interdigitating dendritic cell type

Blood ◽

10.1182/blood.v88.7.2541.bloodjournal8872541 ◽

1996 ◽

Vol 88 (7) ◽

pp. 2541-2548 ◽

Cited By ~ 56

Author(s):

B Herbst ◽

G Kohler ◽

A Mackensen ◽

H Veelken ◽

P Kulmburg ◽

...

Keyword(s):

Dendritic Cell ◽

Progenitor Cells ◽

Mhc Class Ii ◽

Cell Function ◽

Fluorescein Isothiocyanate ◽

Cell Types ◽

Birbeck Granule ◽

Hematopoietic Growth Factors ◽

Necrosis Factor Alpha

We have demonstrated recently that Birbeck granule-positive Langerhans cells (LC) can be derived from CD34+ peripheral blood progenitor cells in the presence of a seven-cytokine cocktail (CC7–7). Here, we show that the sequential use of early-acting hematopoietic growth factors, stem cell factor, interleukin (IL)-3, and IL-6, followed on day 8 by differentiation in the two-factor combination IL-4 plus granulocytemacrophage colony-stimulating factor (GM-CSF) (CC4GM) is more efficient and allows the cells to be arrested in the LC stage for more than 1 week while continuous maturation occurs in CC7–7. Maturation of LC to interdigitating dendritic cells (DC) could specifically be induced within 60 hours by addition of tumor necrosis factor-alpha (20 ng/mL) or lipopolysaccharide (100 ng/mL). Using LC that had been enriched to greater than 90% CD1a+ cells by an immunoaffinity column, we were able to define clear-cut differences between LC and DC that corroborate data of the respective cells derived from epithelial borders (LC) or from lymph nodes (LN) and spleen (DC). Thus, molecules and functions involved in antigen (AG) uptake and processing were highly expressed in LC, while those involved in AG presentation were at maximum in DC. LC were CD1a+2 DR+2, CD23+, CD36+, CD80-, CD86-, and CD25-, while DC were CD1a+/- DR+3, CD23-, CD36-, CD80+, CD86+2, and CD25+, CD40 and CD32 were moderately expressed and nearly unchanged on maturation, in contrast to monocyte-derived DC. Macropinocytosis of fluorescein isothiocyanate-dextran was dominant in LC, as were multilamellar major histocompatibility complex (MHC) class II compartments (MIICs), which were detected by electron microscopy. The functional dichotomy of these cell types was finally supported by testing the AG-presenting cell function for tetanus toxoid to primed autologous T-cell lines, which was optimal when cells were loaded with AG as LC and subsequently induced to become DC.

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