The novel phorbol ester 12-deoxyphorbol 13-(3E,5E-decadienoate) [1] was isolated as the anti-HIV principle of Excoecaria agallocha leaves and stems collected in northwest Australia. The structure was determined by spectral means. Compound 1 was also a potent displacer of [3H]-phorbol dibutyrate from rat brain membranes.

The oxidizing mitogens, sodium periodate and galactose oxidase, induce proliferation ofT cells by generation of aldehyde moieties on cell surface glycoproteins (1-3). A brief (30-min) incubation of lymphocytes with these agents is sufficient to generate the mitogenic signal. The oxidizing agent can then easily be removed by washing the cells. These procedures provide a useful tool for investigation of soluble factors that are released from activated lymphocytes and that may play a role in mediating lymphocyte activation. [8,9]). These factors have a variety of biological activities, the most striking being the induction of proliferation in activated lymphocytes, the activation of cytotoxic T cells (CTL), and the maintenance of such cells in long-term tissue culture. We report here that a mitogenic or growth factor is produced by human lymphocytes activated by a brief treatment of the cells with neuraminidase and galactose oxidase (NAGO). The soluble factors produced by NAGO-stimulated lymphocytes are'mitogenic for nonproliferating cells that have previously been exposed to mitogens or allogeneic cells, or that have been incubated without mitogens for 7-14 d. The NAGO-induced factors do not produce proliferation in freshly isolated, unprimed peripheral blood lymphocytes. Moreover, these soluble factors induce differentiation of MLC memory cells to secondary CTL. Materials and MethodsHuman peripheral blood mononuclear cells (PBL) were obtained from healthy normal volunteers, age 21-47 yr, by Ficoll (Pharmacia Fine Chemicals, Div. of Pharmacia, Inc., Piscataway, N. J.) -Hypaque (Winthrop Laboratories, New York) gradient centrifugation as previously described (10). Lectin-induced memory cells were prepared by adding PHA (2 #g/ ml) or Con A (2 pg/ml) to PBL (10e/ml) that were suspended in RPMI-1640 (Grand Island Biological Co., Grand Island, N. Y.) that contained 5% fetal calf serum, 100 U/ml of penicillin, and 100 #g/ml of streptomycin (RPMI-1640 medium). NAGO-induced memory cells were prepared by exposing PBL (10-20 × 10e/ml), suspended in phosphate-buffered saline (PBS), to 50 U/ml of neuraminidase and 2.6 U/ml of galactose oxidase for 30 min at 37°C in a shaking water bath. The treated PBL were then washed twice with PBS and resuspended in RPMI-1640 medium that contained D-galactose (5 mg/ml). The mitogen-treated memory cells

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Basal expression of the glycoprotein hormone alpha-subunit gene in pituitary gonadotrophs is partially dependent on a gonadotroph specific element (GSE) which binds the nuclear receptor, steroidogenic factor-1 (SF-1). We have used surface plasmon resonance (SPR) to determine the association (kappa ass), dissociation (kappa diss) and affinity (KA) constants of SF-1 binding to immobilized oligonucleotides containing either the GSE consensus motif or a GSE mutant with a 2 bp substitution in the GSE site (GSEMUT). In vitro translated SF-1 protein bound the consensus GSE with a threefold increase in affinity constant (P<0.01) compared with the GSEMUT. This was due primarily to a significant increase (P<0.05) in the kappa ass for SF-1 to the GSE and a slower kappa diss (P<0.05). The binding interaction was specific and could be significantly inhibited (P<0. 001) by either anti-SF-1 antibody or excess non-biotinylated GSE. The addition of 14 bp wild-type flanking sequences significantly reduced the affinity of SF-1 to both the GSE (P<0.05) and the GSEMUT (P<0.01). This was due to a significant (P<0.01) decrease in kappa ass for the wild-type and mutant long oligonucleotides compared with the short GSE. Nuclear extracts from alphaT3-1 gonadotroph cells also bound the GSE and GSEMUT, giving kappa diss values which were two- to threefold slower than those obtained with in vitro translated SF-1. Thus, SPR is a powerful technique for examining kinetic interaction between SF-1 and its binding site, and is able to demonstrate the effects of mutations and flanking sequences on that interaction.

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