Fetus-Placenta-NewbornSoluble HLA-G circulates in maternal blood during pregnancy☆,☆☆
Section snippets
Material and methods
Serum samples from nonpregnant female control subjects (n = 44) were obtained from the Community Blood Center of Greater Kansas City with the kind assistance of G. Tegtmeier, director of the Viral Testing Laboratory. Serum samples from pregnant women (n = 137) were collected between 1980 and 1985 from women with and without diabetes as described elsewhere.20 The samples were continuously maintained at –80°C and were shipped to the University of Kansas Medical Center on dry ice. The 137 samples
Results
The capture ELISA that used monoclonal and polyclonal antibodies directed toward an amino acid sequence derived from intron 4 specifically detected sHLA-G in serum, as determined by inclusion of positive and negative control preparations in each experiment. The positive control preparation consisted of undiluted supernatant culture medium from an HLA-G–transfected mouse fibroblast cell line, the S14/8 cells. The mean (±SEM) specific binding for S14/8 supernatants in 23 separate experiments was
Comment
The data presented in this report show for the first time that sHLA-G circulates in mothers during pregnancy. Multiple control preparations were used to verify the specificity and sensitivity of the capture ELISA. Supernatant culture media of the HLA-G–transfected mouse fibroblast cell line S14/8, which has been shown previously to transcribe messenger ribonucleic acid encoding for sHLA-G,12 was used as a positive control preparation. Values in supernatants were consistently 2-fold greater than
Acknowledgements
We appreciate the kind gifts by Drs G. Tegtmeier and P. Brown of serum samples from nonpregnant control subjects and cord blood, and we acknowledge the expert technical assistance of T. Phillips and S. Platt.
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Cited by (0)
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Supported by grants from the National Institutes of Health awarded to Joan S. Hunt, PhD (HD26429), Daniel E. Geraghty, PhD (AI31874), and Carole Ober, PhD (HD27626) and by core facilities of the Kansas Reproductive Science National Institutes of Health P30 Center (HD33994) and the Kansas Mental Retardation Research Center (HD02528). Wenjiang Chu, MD, PhD, was supported by a fellowship from the Kansas Health Foundation Training Program.
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Reprint requests: Joan S. Hunt, PhD, Department of Anatomy and Cell Biology, University of Kansas Medical Center, 3901 Rainbow Blvd, Kansas City, KS 66160-7400.