Mechanism of action of maternal serum on the interleukin2 receptor expression.

Neoplastic Jurkat cells were submitted to a PHA stimulation test after a preincubation in maternal or nulliparous serum (10% dilution). The Il2R expression was significantly downregulated among maternal serum treated cells. Retroplacental serum was significantly more inhibitive than peripheral maternal serum (P less than 0.

Modulation of B cell stimulation by maternal serum.

Anti-IgM stimulation of B cells is decreased in the presence of maternal serum as compared to control media. This inhibiting influence of maternal serum is observed during the priming of the B cells. The progression of B cells into cellular proliferation was not influenced by maternal serum.

Modulation of the HLA class II antigen at a molecular level by maternal serum among cord blood cells and unrelated lymphocytes.

A retroplacental serum factor responsible for the downregulation of the MHC class II antigen expression has been described [1]. We found that maternal serum had the same property. The HLA class II modulating activity is however diminished in the presence of maternal serum as compared to retroplacental serum suggesting that the IA like inhibiting factor is released at the fetomaternal interface.

The interleukin-2 receptor on cord blood and nulliparous mononuclear cells is downregulated by maternal and cord blood serum.

The concentration of interleukin-2 receptor (IL-2R) on maternal, cord blood and unrelated nulliparous mononuclear cells has been studied after a previous phytohaemagglutinin (PHA) stimulation. Furthermore, the inhibitive action of maternal and cord blood serum on the IL-2R expression of stimulated nulliparous and cord blood lymphocytes has been shown. A downregulation of the [3H]-thymidine uptake by these PHA treated cells previously incubated in maternal and cord blood serum has been observed.

Modulation of the interleukin 2 receptor by maternal and cord blood serum.

In this report, the potential inhibitive action, of maternal serum (retroplacental and peripheral), and cord blood serum on the expression of the Il2r has been studied. Calf and male serum were used as a control. In order to have an optimal Il2r expression, a previous PHA cellular stimulation was performed.