Perinatal changes in serum mannose-binding protein (MBP) levels.

Changes in serum levels of mannose-binding protein (MBP) from day 0 through day 5 after birth were analyzed for normal newborn infants. A considerable amount of MBP (about 1 microgram/ml) was already present in serum at birth. This level started to elevate from day 2 and attained the highest level in a human lifetime (about 2.5 micrograms/ml) within 5 days after birth. Results indicate that MBP can be produced at birth in response to environmental changes.