Impaired <i>in vitr</i><i>o</i> Response of Circulating Lymphocytes to Phytohemagglutinin in Down’s Syndrome: Dose- and Time-Response Curves and Relation to Cellular Immunity

Derangements of immunoglobulin levels, phytohemagglutinin responsiveness and T and B cell markers in Down's syndrome at different ages

“…This association is also a characteristic feature of Down's Syndrome (DS) [ I , 21. In fact, t h e immune status of patients with DS has been the object of several investigations (reviewed by Rigas et al [3]), often with contradictory results, much of which is likely t o arise from the lack of systematic studies.…”

Curvas padrão pôndero-estatural de portadores de Síndrome de Down procedentes da região urbana da cidade de São Paulo

“…Havendo referências de que as subclasses do tipo IgG1 e IgG3 estão elevadas e IgG2 e IgG4 estão mais freqüentemente reduzidas no início da adolescência, entre 9 e 12 anos de idade (ANNERÉN et al, 1992). Na resposta da imunidade celular dos portadores de SD são descritos vários comprometimentos por anormalidades estruturais: do timo (LEVIN et al, 1979;TROISI et al, 1985); 33 da diferenciação dos linfócitos-T, prejudicando a imunocompetência para vírus, fungos, bactérias e síntese de anticorpo (MURPHY et al, 1995); da produção de interleucinas (GEREZ et al, 1991); e da resposta ao interferon-γ (INFγ) (SASAKI & OBARA, 1969;RIGAS et al, 1970;MURPHY et al, 1993;TORRE et al, 1995).…”

Immunoregulatory CD4+ CD45R+ suppressor/inducer T lymphocyte subsetsand impaired cell-mediated immunity in patients with Down's syndrome

“…The total T cell number has been reported by some laboratories to be normal (Reiser et al, 1976;Epstein & Epstein, 1980) and by others to be depressed (Gulliya & Dowben, 1983). Although values reported for the helper/ inducer (CD4+) to suppressor/cytotoxic (CD8+) ratio of lymphocytes in the blood have been inconsistent (Church et al, 1983;Burgio et al, 1983;Gupta et al, 1983;Karttunen et al, 1984;Philip et al, 1986), the in vitro T lymphocyte responses to a specific bacterial antigen, tetanus toxoid (Philip et al, 1986), and to phytohaemagglutinin (PHA), pokeweed mitogen (PWM), and mitogenic CD3+ antibody are decreased (Rigas et al, 1970;Bertotto et al, 1987). Thus, the defect is believed to involve T rather than B cells, although extensive studies in vitro have failed to reach a consensus regarding the cause of the deficiency.…”