Chemotactic activity for polymorphonuclear leukocytes: meconium versus meconium-stained amniotic fluid.
OBJECTIVE
Our previous study indicated that meconium-stained amniotic fluid (turbid AF) possessed a potent chemotactic activity for leukocytes, which may be dependent on interleukin-8. It is not known, however, whether meconium itself possesses this chemotactic activity.


METHODS
Meconium samples were collected from mature neonates with and without turbid AF. A 5% meconium suspension in phosphate buffered saline was prepared and measured for its chemotactic activity for leukocytes using the blind well chamber technique. Concentrations of IL-8, TNFalpha and IL-1beta were also measured with ELISA.


RESULTS
The number of leukocytes that migrated to the meconium suspension (35 +/- 27) was comparable with that of the clear AF (31 +/- 37), but was significantly lower than that of the turbid AF (184 +/- 62, P < 0.0001). The meconium suspension contained much lower levels of IL-8, TNFalpha and IL-1beta than the turbid AF.


CONCLUSIONS
Meconium itself exhibits a lower chemotactic activity for polymorphonuclear leukocytes than turbid AF in vitro. The leukocyte chemotactic activity of turbid AF does not originate from meconium itself.
Yamada
T
T
Department of Obstetrics and Gynecology, Jichi Medical School, Tochigi, Japan. yamada88@jichi.ac.jp
Matsubara
S
S
Minakami
H
H
Kohmura
Y
Y
Hiratsuka
M
M
Sato
I
I
D000653:Amniotic Fluid / Q000502:physiology*; D002634:Chemotaxis, Leukocyte / Q000502:physiology*; D006801:Humans; D007231:Infant, Newborn; D007375:Interleukin-1 / Q000032:analysis; D016209:Interleukin-8 / Q000032:analysis; D008470:Meconium / Q000502:physiology*; D009504:Neutrophils / Q000502:physiology; D014409:Tumor Necrosis Factor-alpha / Q000032:analysis
D007375:Interleukin-1; D016209:Interleukin-8; D014409:Tumor Necrosis Factor-alpha