Characterization of Human Sertoli Cells in Vitro*

SummaryLupus anticoagulants (LAs) are antibodies which interfere with phospholipid-dependent procoagulant reactions. Their clinical importance is due to their apparent association with an increased risk of thrombo-embolic disease. To date there have been few assays for quantifying the specific activity of these antibodies in vitro and this has hampered attempts to purify and characterize these antibodies. Methods for determining phospholipid-dependent generation of thrombin and factor Xa are described. Isolated IgG fractions from 7 of 9 patients with LAs were found to reproducibly inhibit enzyme generation in these assay systems, permitting quantitative expression of inhibitor activity. Different patterns of inhibitory activity, based on the relative inhibition of thrombin and factor Xa generation, were found, further substantiating the known heterogeneity of these antibodies. These systems may prove helpful in further purification and characterization of LAs.

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Characterization of the Original Christmas Disease Mutation (Cysteine 206 → Serine): From Clinical Recognition to Molecular Pathogenesis

Thrombosis and Haemostasis ◽

10.1055/s-0038-1648381 ◽

1992 ◽

Vol 67 (01) ◽

pp. 063-065 ◽

Cited By ~ 6

Author(s):

Sherryl A M Taylor ◽

Jacalyn Duffin ◽

Cherie Cameron ◽

Jerome Teitel ◽

Bernadette Garvey ◽

...

Keyword(s):

Nucleotide Substitution ◽

Novel Mutation ◽

Factor Ix ◽

Causative Mutation ◽

Coding Region ◽

Body Of Knowledge ◽

Polymerase Chain ◽

Splice Junctions

SummaryChristmas disease was first reported as a distinct clinical entity in two manuscripts published in 1952 (1, 2). The eponym associated with this disorder, is the surname of the first patient examined in detail and reported by Biggs and colleagues in a paper describing the clinical and laboratory features of seven affected individuals (3). This patient has severe factor IX coagulant deficiency (less than 0.01 units/ml) and no detectable circulating factor IX antigen (less than 0.01 units/ml). Coding sequence and splice junctions of the factor IX gene from this patient have been amplified in vitro through the polymerase chain reaction (PCR). One nucleotide substitution was identified at nucleotide 30,070 where a guanine was replaced by a cytosine. This mutation alters the amino acid encoded at position 206 in the factor IX protein from cysteine to serine. The non conservative nature of this substitution, the absence of this change in more than 200 previously sequenced factor IX genes and the fact that the remainder of the coding region of this gene was normal, all provide strong circumstantial evidence in favour of this change being the causative mutation in this patient. The molecular characterization of this novel mutation in the index case of Christmas disease, contributes to the rapidly expanding body of knowledge pertaining to Christmas disease pathogenesis.

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Follicle-stimulating hormone-dependent estrogen secretion by rat Sertoli cells in vitro: Modulation by calcium

Acta Endocrinologica ◽

10.1530/acta.0.1250280 ◽

1991 ◽

Vol 125 (3) ◽

pp. 280-285 ◽

Cited By ~ 6

Author(s):

J. Alan Talbot ◽

Ann Lambert ◽

Robert Mitchell ◽

Marek Grabinski ◽

David C. Anderson ◽

...

Keyword(s):

Sertoli Cells ◽

Culture Medium ◽

Follicle Stimulating Hormone ◽

Dibutyryl Camp ◽

Immature Rat ◽

Estradiol Secretion ◽

Old Rats ◽

Stimulating Hormone

Abstract We have investigated the role of Ca2+ in the control of FSH-induced estradiol secretion by Sertoli cells isolated from 8-10 days old rats. Exogenous Ca2+ (4-8 mmol/1) inhibited FSH-stimulated E2 secretion such that, with 8 mmol/l Ca2+ and FSH (8 IU/l) E2 secretion decreased from 2091±322 to 1480±84 pmol/l (p<0.002), whilst chelation of Ca2+ in the culture medium with EGTA (3 mmol/l) increased E2 secretion from 360±45 to 1242±133 pmol/l) in the absence of FSH. Further, EGTA (3 mmol/l) markedly potentiated FSH (8 IU/l), forskolin (1 μmol/l) and dibutyryl cAMP (1 mmol/l)-stimulated E2 secretion. Addition of the Ca2+ ionophores, ionomycin (2-5 μmol/l) and A23187 (2 μmol/l), inhibited FSH (8 IU/l)-stimulated E2 secretion by >80%. The effect of ionomycin was totally reversible, whereas that of A23187 was irreversible. Ionomycin (5 μmol/l) had no effect on EGTA-induced E2 secretion in the absence of FSH, but reduced EGTA-provoked E2 secretion by 59% in the presence of FSH (8 IU/l). Similarly, forskolin- and dibutyryl cAMP-provoked E2 production was inhibited 46-50% by ionomycin (5 μmol/l). We conclude that FSH-induced E2 secretion from immature rat Sertoli cells is modulated by intra- and extracellular Ca2+.

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