Frigen II improves the reliability of measurement of interleukin-1 related substances in amniotic fluid.
BACKGROUND
To investigate the role of interleukin-1 related substances in amniotic fluid in normal term labor without intrauterine infection.


METHODS
Amniotic fluid samples were collected from forty-one patients with various backgrounds. A novel pre-assay treatment using Frigen II was introduced to improve the recovery rates of cytokines, i.e., interleukin-1alpha, interleukin-1beta and interleukin-1 receptor antagonist, prior to ELISA assay. Urine samples from newborn infants were also tested.


RESULTS
The concentrations of interleukin-1alpha, interleukin-1beta and interleukin-1ra were significantly higher in samples from normal vaginal delivery. The higher levels of interleukin-1alpha were also observed in samples from preterm labor without infection. Preterm infants produced more of interleukin-1 receptor antagonist in urine compared with term infants.


CONCLUSIONS
This study provides evidence of the possible involvement of interleukin-1 related substances in labor without signs of infection. The data from newborn urine suggests that amniotic interleukin-1ra originates from the fetus. However, amniotic fluid interleukin-1alpha and interleukin-1beta may be derived from maternal tissue, such as decidua.
Ishihara
O
O
Department of Obstetrics & Gynecology, Saitama Medical Center, Saitama Medical School, Kawagoe, Japan.
Saitoh
M
M
Kinoshita
K
K
Takanashi
H
H
Arai
Y
Y
Kitagawa
H
H
D000653:Amniotic Fluid / Q000737:chemistry*; D005617:Chlorofluorocarbons, Methane; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D053590:Interleukin 1 Receptor Antagonist Protein; D007375:Interleukin-1 / Q000032:analysis*; D007743:Labor, Obstetric / Q000378:metabolism; D007752:Obstetric Labor, Premature / Q000378:metabolism; D011247:Pregnancy; D011933:Reagent Kits, Diagnostic; D017472:Receptors, Interleukin-1 / Q000037:antagonists & inhibitors; D012795:Sialoglycoproteins / Q000032:analysis
D005617:Chlorofluorocarbons, Methane; C507763:IL1RN protein, human; D053590:Interleukin 1 Receptor Antagonist Protein; D007375:Interleukin-1; D011933:Reagent Kits, Diagnostic; D017472:Receptors, Interleukin-1; D012795:Sialoglycoproteins; C009755:fluorocarbon 22