Donald Johnson

Immunoassay reagents for psychoactive drugs. I: The method for the development of antibodies specific to amitriptyline and nortriptyline

Amitriptyline and nortriptyline were structurally modified by the attachment of spacer arms to the aromatic ring which were subsequently attached to bovine serum albumin (BSA). Rabbits inoculated with these conjugates yielded polyclonal antisera with high selectivity and good titers. This approach required novel spacer arms and new conjugation methods. The antisera produced were characterized with respect to their cross-reactivity with amitriptyline, nortriptyline and their hydroxy metabolites as well as selected structurally related compounds.

Immunoassay reagents for psychoactive drugs: II. The method for the development of antibodies specific to imipramine and desipramine

Imipramine and desipramine were structurally modified by the attachment of spacer arms to the aromatic ring which were subsequently attached to bovine serum albumin. This approach utilized novel spacer arms and conjugation methods. This method yielded antisera with excellent selectivity and good titers. Rabbits were used to raise the antisera and the antibodies produced were characterized with respect to their cross-reactivity with imipramine, desipramine and hydroxy metabolites as well as selected structurally related compounds.

Human T Cell Growth Factor (TCGF) produced by repeated stimulation of non-adherent human lymphocytes

T cell growth factor (TCGF) has become a valuable means of maintaining T lymphocytes in long-term culture and of studying T cell function. Numerous problems have been met in the production of TCGF of consistently good quality and in the maintenance of human T cell lines over long periods. We have investigated optimal conditions for TCGF production, and simplified assay systems for TCGF activity. The best TCGF production was obtained by short-term treatment with high concentrations of phytohemagglutinin (PHA). The TCGF producing lymphocytes could be re-used for TCGF production up to 1 month after the first treatment course. Human cultured T cell lines, fresh lymphocytes, short-term PHA stimulated lymphocytes and cultured marmoset T lymphocyte lines were all used for assay of TCGF. We recommend PHA stimulation of human lymphocytes for this assay on a routine basis, comparing results with a standard TCGF batch and calculating a growth index. Adherent cells impair TCGF production. Optimal TCGF production was seen when lymphocyte preparations without adherent cells from different donors were used.

Chromosomes and cell surface markers of marmoset lymphocytes and Epstein-Barr virus-transformed marmoset cell lines

The G-banded karyotypes of both normal lymphocytes and Epstein-Barr virus (EBV)-transformed lymphocytes of cotton-topped marmosets (Saguinus oedipus) were examined. The marmoset lymphocytes and EBV-transformed lymphoblastoid cells had normal diploid chromosomes (2n = 46) with no specific cytogenic change associated with transformation in vitro. EBV-transformed marmoset lymphocytes expressed the cell surface markers of B lymphocytes and EB viral antigens.

Interaction of Herpesvirus Ateles and Herpesvirus Saimiri with Primate Lymphocytes

A semiquantitative infectious bioassay, described by Sairenji and Hinuma for the measurement of Epstein-Barr virus (EBV) receptors, was adapted to study the adsor

Relationship between Herpesvirus ateles-associated Nuclear Antigen (HATNA) and the Number of Virus Genome Equivalents in HVA-carrying Lymphoid Lines

A DNA-binding antigen (HATNA) was demonstrated in 7 out of 14 cell lines carrying Herpesvirus ateles (HVA) by the acid-fixed nuclear-binding technique. The seven HATNA-positive lines had means of 95, 96, 103, 177, 240, 343 and 326 virus genome equivalents/cell. For the seven HATNA-negative lines, the figures were 4, 8, 10, 33, 39, 72 and 110. This indicates a relationship between the number of HVA genome equivalents/cell and the detectability of HATNA. This association was independent of the virus producer status of the lines.

Interaction of herpesvirus ateles with marmoset lymphocytes. II. Identification of target cell population and stimulation of DNA synthesis after infection in vitro

Herpesvirus ateles (HVA) can transform lymphocytes from certain nonhuman primates, leading to established lymphoid lines. We have found that HVA adsorbs preferentially to the T lymphocytes (E-rosette-forming cells) of marmoset monkeys and that DNA synthesis is induced within 2–6 days after infection.

NATURAL KILLER CELL-LIKE CYTOTOXICITY MEDIATED BY HERPESVIRUS TRANSFORMED MARMOSET T CELL LINES

Publisher Summary This chapter examines natural killer (NK) cell-like cytotoxicity mediated by herpesvirus transformed marmoset T-cell lines. In a study described in the chapter, peripheral blood lymphocytes from adult cotton-topped and white-lipped marmosets and from normal human donors were separated by centrifugation on Ficoll/Isopaque and nylon wool. Permanent lymphoid cell lines were established by transformation of marmoset lymphocytes with cell-free Herpesvirus ateles (HVA) obtained from supernatants of HVA-infected marmoset kidney fibroblasts or cocultivation with HVA-producing tumor or lymphoid cells. Seven different HVA– Herpesvirus saimiri (HVS) transformed cell lines were tested for surface markers, killing of different target cells, and other functional characteristics. The cytotoxic specificity was primarily directed against human T-cell lines derived from ALL. The activity of the individual lines was found to be different in intensity and also varied in time when serially tested on a monthly basis. The lines had surface markers typical for the T-cell phenotype and lacked the ability to mediate lectin-dependent cellular cytotoxicity (LDCC) and antibody-dependent cellular cytotoxicity (ADCC). In cold-target inhibition tests (against hot-target Molt-4), K-562 was most inhibitory followed by Molt-4 itself. No inhibition was seen with cold targets Daudi and YAC-1.