ZnCl2 over a very narrow concentration range was found to be mitogenic for hamster lymph node cells but not for thymocytes or splenocytes. Maximal leucine, [3H]uridine, and [3H]thymidine incorporation. Addition of 10 micron ZnCl2 was found to greatly enhance the stimulation observed with the B-lymphocyte mitogen lipopolysaccharide but not with dextran sulfate or the T-lymphocyte mitogen lipopol...

Platelets contain mitogenic activities for MCF-7 human breast cancer cells when assayed under serum-free chemically defined conditions. Purification from outdated human platelets identified insulinlike growth factor I (IGF-I) as the most potent breast cancer cell mitogen in lysates (Karey KP, Sirbasku DA: see accompanying article, this issue). In this study the release and subcellular localizat...

Ophthalmic mycoses caused by infectious fungi are being recognized as a serious concern since they lead to total blindness. Cephalosporium is one amongst several opportunistic fungal species implicated in ophthalmic infections leading to mycotic keratitis. A mitogenic lectin has been purified from the mycelia of fungus Cephalosporium, isolated from the corneal smears of a keratitis patient. Cep...

Goat and rat antisera directed against Friend leukemia virus (anti-FLV) were found to be B-lymphocyte mitogens stimulating DNA synthesis in these cells but not in T lymphocytes. Membrane fluorescence microscopy showed that anti-FLV reacts with a subset of B lymphocytes of which the majority express immunoglobulin mu chains. The mitogenic effect was found with all mouse strains tested including ...

Platelets contain mitogenic activities for MCF-7 human breast cancer cells when assayed under serum-free chemically defined conditions. Purification from outdated human platelets identified insulinlike growth factor I (IGF-I) as the most potent breast cancer cell mitogen in lysates (Karey KP, Sirbasku DA: see accompanying article, this issue). In this study the release and subcellular localizat...

Reversed micelles were used to extract lectin from red kidney beans and factors affecting reverse micellar systems (pH value, ionic strength and extraction time) were studied. The optimal conditions were extraction at pH 4-6, back extraction at pH 9-11, ion strength at 0.15 M NaCl, extraction for 4-6 minutes and back extraction for 8 minutes. The reverse micellar system was compared with tradit...

Cellular proliferation depends on the integration of mitogenic stimuli with environmental conditions. Increasing evidence suggests that microRNAs play a regulatory role in this integration. Here we show that during periods of cellular quiescence, mature microRNAs are stabilized and stored in Argonaute protein complexes that can be activated by mitogenic stimulation to repress mitogen-stimulated...

We investigated native structures and mitogenic properties of pokeweed lectin-D isoforms (PL-D1 and -D2) on human peripheral blood lymphocytes along with other isolectins (PL-A to -C). Both native PL-D isoforms appeared to behave as monomers. PL-D2 proliferated the lymphocytes like PL-C, whereas PL-D1 had no mitogenicity. PL-D1 acquired mitogenic activity after trimming of the C-terminal dipept...

Polyadenylic-polyuridylic acid complexes (poly A:U) at the 1-5 mu g level, were mitogenic for spleen cells when given intravenously to normal Balb or cortisone-treated mice. Similarly, mitogenicity was evident when poly A:U was added to tissue culture fluids containing spleen cells from normal or cortisone-treated mice, or bone marrow cells from normal mice. Under these conditions, this adjuvan...

Long-term cultures of bovine retinal capillary endothelial cells (BRCEC) have been established using bovine retinal pericyte conditioned medium (PCM). PCM had greater mitogenic activity on BRCEC than unconditioned medium (P less than 0.01). The mitogenic activity of PCM was not cell specific since bovine Tenon's fibroblast conditioned medium also had significant activity. PCM's activity was not...