Grandmaternal cells in cord blood

Area of Science:

• Immunology
• Genetics
• Cell Biology

Background:

• Fetal and maternal cells are exchanged during pregnancy, leading to microchimerism (Mc).
• Maternal cells can acquire cells from their own mother, potentially transferring them to their child.
• Grandmaternal microchimerism (GdMMc) in cord blood has been theoretically proposed but not yet demonstrated.

Purpose of the Study:

• To investigate the presence of grandmaternal microchimerism (GdMMc) in human cord blood (CB).
• To explore potential correlations between GdMMc and factors like invasive prenatal procedures and HLA compatibility.

Main Methods:

• Human Leukocyte Antigen (HLA)-specific quantitative PCR assays were used.
• 28 cord blood samples from healthy primigravid women were analyzed.
• GdMMc was tested in whole blood and various isolated cell types.

Main Results:

• GdMMc was detected in 18% of cord blood samples, distinct from maternal Mc.
• GdMMc quantities were significantly lower than maternal Mc.
• The presence of GdMMc correlated with increased risk of aneuploidies and invasive prenatal procedures.
• Significantly decreased HLA compatibility was observed in families with GdMMc in CB.

Conclusions:

• Transgenerational cell transfer, evidenced by GdMMc, is demonstrated in human cord blood.
• GdMMc may have implications for immunology and evolution.
• Further research is needed to determine if GdMMc transfer is passive or active and if prenatal procedures influence it.