Decreased polyamine content of concanavalin a stimulated lymphocytes in Down's syndrome subjects

Increased polyamine content is associated with increased rates of cell growth. Several Down's syndrome (D.S.) tissues have been shown to have decreased growth rates. Studies were undertaken to determine if the polyamine content of stimulated D.S. lymphocytes was similar to that of stimulated normal cells. Lymphocytes were isolated and cultured in the presence of Concanavalin A for 4 or 5 days. Polyamines were than extracted and quantitated. After 4 days spermidine content for normal cells was 930.9 +/- 127 and for D.S. cells 489.2 +/- 113.1 nmoles/10(9) cells (P less than 0.025). Spermine content of normal cells was 1152.8 +/- 157.4 and for D.S. cells 533.9 +/- 82.0 (P less than 0.005). After 5 days in culture spermidine content of normal cells was 803.0 +/- 75.9 and for D.S. cells 446.2 +/- 76.5 nmoles/10(9) cells (P less than 0.005). Spermine content was 1155.7 +/- 121.9 for normal cells and 555.1 +/- 68.4 nmoles/10(9) for D.S. cells. Decreased content of polyamines in D.S.-stimulated lymphocytes is most probably due to decreased rate of polyamine synthesis. Decreased content of polyamines in response to stimulation may be a factor in decreased growth rates and altered immune function seen in D.S. patients.