Natural killer cell function of human neonatal lymphocytes

Area of Science:

• Immunology
• Developmental Biology

Background:

• Natural killer (NK) cells are crucial for innate immunity.
• NK cell activity and maturation during fetal development are not fully understood.

Purpose of the Study:

• To compare NK cell activity between term cord blood and adult peripheral blood.
• To investigate the effect of interferon-alpha on NK cell function in different age groups.

Main Methods:

• 51Cr release assay was used to measure NK cell activity.
• NK cell activity was assessed in 30 term cord blood samples and 20 adult peripheral blood samples.
• The impact of human leukocyte interferon (IFN-alpha) on NK cell function was evaluated in vitro.

Main Results:

• NK cell activity was significantly lower in cord blood (27.4% +/- 11.8%) compared to adult blood (39.6% +/- 11.4%) at a 50:1 effector:target ratio.
• Adult males exhibited higher NK cell activity than adult females, with no significant sex-based difference observed in cord blood.
• IFN-alpha enhanced the in vitro NK cell function in lymphocytes from both newborns and adults.

Conclusions:

• Human NK cells appear and mature during intrauterine development.
• NK cell activity in newborns is lower than in adults but can be enhanced by IFN-alpha, suggesting potential for therapeutic intervention.