Different optimal PHA concentrations for stimulation of Chinese hamster lymphocytes in cultures supplemented with foetal calf serum or horse serum

1. Contact-inhibited confluent monolayers of WI-38 human diploid fibroblasts can be stimulated to divide by replacing the medium with fresh medium containing 30′ foetal calf serum. 2. Of the cells 40–75′ are stimulated to divide with a peak DNA synthesis between 15 and 21h and a peak mitotic index between 28 and 30h after stimulation. 3. In the first 12h before the initiation of DNA synthesis there is a biphasic increase in the incorporation of [3H]uridine into RNA of whole cells. 4. This is paralleled by a similar biphasic stimulation of chromatin template activity measured in vitro in a system in which purified cell chromatin is incubated with an exogenous RNA polymerase isolated from Escherichia coli. 5. The changes in chromatin template activity are believed to represent activation of the genome, with more sites available for RNA synthesis, and to account almost entirely for the changes in RNA synthesis occurring in the whole cell.

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Megakaryocytic Progenitors in Long Term Cultures from MDS Patients.

Blood ◽

10.1182/blood.v106.11.4924.4924 ◽

2005 ◽

Vol 106 (11) ◽

pp. 4924-4924

Author(s):

Maria Juliana Majado ◽

María I. Macizo ◽

Consuelo González-García ◽

Eduardo Salido ◽

José A. Molina ◽

...

Keyword(s):

Bone Marrow ◽

Culture Medium ◽

Horse Serum ◽

Calf Serum ◽

Methyl Cellulose ◽

Refractory Anemia ◽

Foetal Calf Serum ◽

Cell Counts ◽

Control Bone

Abstract Introduction: bone marrow long-term cultures (LTC) have been reported to produce very poor adherent stromal layer in MDS, but there are not many studies about the behaviour of the progenitor cells in supernatant culture medium. In this study we report the results of megakaryocytic progenitors (CFU-MK) in the supernatant of LTC of patients with refractory anemia (RA). Material and method: LTCs were performed to 11 RA patients and to 13 normal multiorgan donors as control. Bone marrow red cells were sedimented with 1% methyl-cellulose and seeded for LTC in 10ml flasks (Nalge Nunc International), with Iscover medium supplemented with horse serum, foetal calf serum, hydrocortisone and carbonic air, at a final concentration of 1x106 per ml. Flasks were placed in an incubator for 8 weeks. Half culture medium volume was renovated weekly, cell counts and assays of CFU-MK (Megacult C, Stem Cell Technologies), were performed. CFU-MK colonies were separated in three groups, containing 3–20 cells, 21–50 cells and more than 50 cells. Student t-test was used for statistical comparisons. Results: Are in the following table, expressed as mean + standard desviation. After the third week no colony growth was observed in normal such as in MDS. Growth of CFU-MK colonies containing more than 50 cells was higher in basal control bone marrow, no statistical differences were found in the rest of the cultures. Results CFU-MK(3–30 Cells) CFU-MK(20–50 Cells) CFU-MK (>50 Cells) CFU-MK total w: week Control basal 15.75±15.79 3.33±5.42 4.88±7.44 22.42±26.43 RA basal 7.85±8.66 0.80±1.01 0.70±0.98 9.45±9.46 t-St ns ns 0.047 ns Control w 1 3.54±4.42 0.7±1.44 0.74±1.48 4.98±6.62 RA w 1 3.29±4.52 0.29±0.93 0.25±0.67 3.82±5.65 t-St ns ns ns ns Control w 2 0.55±1.14 0.07±0.24 0.05±0.25 0.67±1.43 RA w 2 0.18±0.32 0.00±0.00 0.04±0.13 0.21±0.38 t-St ns ns ns ns Control w 3 0.18±0.53 0.00±0.00 0.00±0.00 0.18±0.53 RA w 3 0.00±0.21 0.00±0.00 0.00±0.00 0.00±0.21 t-St ns ns Discussion: No important difference was found in LTC supernatant CFU-MK in our RA patients, and this supports the idea that the stromal damage is more important, in the pathophysyology of MDS, than that of the stem cells.

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P18. Generation of inorganic pyrophosphate (PPi) by human bone cells, stimulation of ecto-nucleoside triphosphate (NTP) pyrophosphatase activity by factors present in foetal calf serum

Bone ◽

10.1016/8756-3282(89)90042-2 ◽

1989 ◽

Vol 10 (2) ◽

pp. 152-152

Author(s):

BO Oyajobi ◽

RGG Russell ◽

AM Caswell

Keyword(s):

Bone Cells ◽

Calf Serum ◽

Human Bone ◽

Nucleoside Triphosphate ◽

Foetal Calf Serum ◽

Inorganic Pyrophosphate ◽

Pyrophosphatase Activity ◽

Stimulation Of

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Control of proteoglycan biosynthesis. Further studies on the effect of serum on cultured bovine articular cartilage

Biochemical Journal ◽

10.1042/bj2370741 ◽

1986 ◽

Vol 237 (3) ◽

pp. 741-747 ◽

Cited By ~ 21

Author(s):

D J McQuillan ◽

C J Handley ◽

H C Robinson

Keyword(s):

Articular Cartilage ◽

Dna Synthesis ◽

Half Life ◽

Rna Synthesis ◽

Core Protein ◽

Calf Serum ◽

Proteoglycan Synthesis ◽

Foetal Calf Serum ◽

Bovine Articular Cartilage ◽

Stimulation Of

Proteoglycan synthesis in explant cultures of adult bovine articular cartilage is stimulated in a dose-dependent manner when the tissue is cultured in the presence of foetal-calf serum. The stimulation of proteoglycan synthesis is paralleled by a similar increase in DNA synthesis; however, when DNA synthesis is inhibited by hydroxyurea the stimulation of proteoglycan synthesis by serum remains essentially the same. The apparent half-life of the pool of proteoglycan core protein precursor was measured in freshly isolated tissue as well as in tissue cultured for 7 days in the presence and in the absence of foetal-calf serum; under all conditions the half-life was the same, suggesting that this value is independent of the net rate of proteoglycan synthesis. In the presence of actinomycin D, an inhibitor of RNA synthesis, there was a difference in the apparent half-life of the available pool of mRNA coding for proteoglycan core protein: 8.5 h for tissue maintained in the presence of serum and 3.8 h for tissue cultured in the absence of serum. It is suggested that proteoglycan synthesis is stimulated by serum factors at the level of DNA-dependent RNA synthesis. Concomitant with an increase in the rate of proteoglycan synthesis induced by the presence of serum in the culture medium, an increase in the concentrations of several glycosyltransferases involved in chondroitin sulphate synthesis was also observed.

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Ethanolamine as well as choline is released to the external medium on phorbol ester and foetal calf serum stimulation of glial cells in primary culture

Biochemical Society Transactions ◽

10.1042/bst019153s ◽

1991 ◽

Vol 19 (2) ◽

pp. 153S-153S ◽

Cited By ~ 2

Author(s):

SHAUN McNULTY ◽

REBECCA SAYNER ◽

MARTIN RUMSBY

Keyword(s):

Primary Culture ◽

Glial Cells ◽

Phorbol Ester ◽

External Medium ◽

Calf Serum ◽

Foetal Calf Serum ◽

Serum Stimulation ◽

Stimulation Of

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The culture of mouse blastocysts in the presence of uterine flushings collected during normal pregnancy, delayed implantation and pro-oestrus

Development ◽

10.1242/dev.41.1.295 ◽

1977 ◽

Vol 41 (1) ◽

pp. 295-300

Author(s):

R. J. Aitken

Keyword(s):

Culture Medium ◽

Cell Transformation ◽

Calf Serum ◽

Normal Pregnancy ◽

Foetal Calf Serum ◽

Delayed Implantation ◽

Simple Medium ◽

Uterine Proteins ◽

Stimulation Of ◽

Blastocyst Hatching

When day-3 mouse embryos were cultured in a simple medium supplemented with uterine fluids of mice autopsied on day 4 of pregnancy, 48 h after administration of oestradiol, or during pro-oestrus, the percentage of blastocysts hatching from the zona pellucida was significantly greater than in unsupplemented medium. In the presence of uterine fluids recovered during delayed implantation this stimulation of blastocyst hatching was not observed. When the culture medium was supplemented with dialysed uterine flushings containing 20 or 30 μg protein/ml, both ‘day 4’ and ‘delay’ uterine proteins were equally effective in enhancing hatching frequency (P < 00·5). The results suggested that ‘delay’ uterine fluids may contain a dialysable inhibitor of blastocyst activity. The putative inhibitor was not effective in the presence of serum, since uterine fluids recovered both on day 4 of pregnancy and during delayed implantation significantly increased the size attained by lastocyst outgrowths in the presence of foetal calf serum (P < 0·001). The percentage of blastocysts exhibiting giant cell transformation and outgrowth was also increased (P < 0·02) by these uterine fluids when the concentration of FCS in the medium was minimal (0·25 %).

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Influence of serum factors on the prevalence of “normal” and “foreign” differentiation pathways in cultures of chick embryo neuroretinal cells

Development ◽

10.1242/dev.62.1.291 ◽

1981 ◽

Vol 62 (1) ◽

pp. 291-308

Author(s):

D. I. de Pomerai ◽

M. A. H. Gali

Keyword(s):

Choline Acetyltransferase ◽

High Glucose ◽

Horse Serum ◽

Calf Serum ◽

Pigment Cells ◽

Retinal Cell ◽

Foetal Calf Serum ◽

Serum Factors ◽

Acetyltransferase Activity ◽

Choline Acetyltransferase Activity

Embryonic (9-day) chick neuroretinal cells transdifferentiate extensively into lens and pigment cells during prolonged culture (4–5 weeks) in media containing foetal calf serum. Medium conditions which promote the attachment and differentiation of neural cells in other culture systems (e.g. horse serum, high glucose levels) both delay the onset and greatly reduce the extent of transdifferentiation in retinal cultures. In the presence of high glucose, horse serum (but not foetal calf serum) also favours cholinergic neuronal differentiation during the early phases of culture, as shown by the levels of choline acetyltransferase activity and accumulation of labelled choline. Substrate conditions have some effect on cholinergic differentiation (promoted by polylysine-coated dishes) but do not affect later transdifferentiation. These effects may be due in part to selective survival or growth of particular retinal cell types under the various medium conditions tested. Cultures stripped of neuronal cells contain negligible choline acetyltransferase activity, but still transdifferentiate into both lens and pigment cells, although more slowly than control cultures. Cell size distributions reveal a significant depletion of the larger cells in high glucose media with foetal calf serum, but not in those with horse serum.

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In vitro stimulation of metacyclogenesis in Leishmania braziliensis, L. donovani, L. major and L. mexicana

Parasitology ◽

10.1017/s0031182097002382 ◽

1998 ◽

Vol 116 (4) ◽

pp. 305-309 ◽

Cited By ~ 58

Author(s):

H. A. ZAKAI ◽

M. L. CHANCE ◽

P. A. BATES

Keyword(s):

Stationary Phase ◽

Cell Body ◽

Calf Serum ◽

Leishmania Braziliensis ◽

Foetal Calf Serum ◽

Acidic Ph ◽

Metacyclic Promastigotes ◽

Stimulation Of

Promastigotes of Leishmania braziliensis, L. donovani, L. major and L. mexicana recently derived from tissue amastigotes were cultured in Schneider's Drosophila medium supplemented with 20% (v/v) heat-inactivated foetal calf serum and 25 μg gentamicin sulfate/ml at pH 5·5. These cultures produced more metacyclic promastigotes in their stationary-phase populations than others cultured at pH 7·0. Metacyclic promastigotes possessed a short ([les ]8 μm) and narrow ([les ]1·5 μm) cell body with a flagellum twice or more the length of the cell body. Promastigotes from acidic cultures were more resistant to complement-mediated lysis and more infective in vivo than those grown at neutral pH. These results demonstrate that induction of metacyclogenesis by acidic pH is a response conserved across a variety of species of Leishmania.

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