Circulating mRNA as diagnostic markers

Abstract

Methods and kits are provided for diagnosing, monitoring, or predicting the conditions of pre-eclaimpsia, fetal chromosomal aneuploidy, and pre-term labor in a pregnant woman, as well as for detecting pregnancy in a woman, by quantitatively measuring in the maternal blood the amount of one or more mRNA species encoding human chorionic gonadotropin β subunit (hCG-β), human placental lactogen (hPL), human corticotropin releasing hormone (hCRH), KiSS-1 metastasis-suppressor (KISS1), tissue factor pathway inhibitor 2 (TPFI2), placenta-specific 1 (PLAC1), or glyceraldehyde-3-phosphate dehydrogenase (GAPDH), and comparing the amount of the mRNA species with a standard control.

Description

CROSS REFERENCE TO RELATED APPLICATIONS

[0001] This application is a divisional of U.S. application Ser. No. 10 / 759,783, filed Jan. 16, 2004. This application also claims priority to U.S. Provisional Application No. 60 / 440,906, filed Jan. 17, 2003, the contents of both are incorporated herein by reference in their entirety.BACKGROUND OF THE INVENTION

[0002] Prenatal diagnosis has been routinely conducted using cells isolated from the fetus through procedures such as chorionic villus sampling (CVS) or amniocentesis. These conventional methods are, however, invasive and present an appreciable risk to both the mother and the fetus despite most careful handling (Tabor et al., Lancet 1:1287-1293, 1986).

[0003] Alternatives to these invasive approaches have been developed for prenatal screening, e.g., to detecting fetal abnormalities, following the discoveries that several types of fetal cells can be found in maternal circulation (Johansen et al., Prenat. Diagn. 15:921-931, 1995) and more impor...

Examples

example 1

Elevated hCRH MRNA Level in Preeclamptic Women

A. Methods

Subjects

[0065]Peripheral blood samples were collected with informed consent and Research Ethics Committee approval from pregnant women, who attended the Department of Obstetrics and Gynecology at the Prince of Wales Hospital, Hong Kong.

[0066]In the first part of this study, blood samples were obtained from 10 healthy pregnant women during the third trimester of gestation. In the second part of the project, 4 pregnant women with uncomplicated pregnancy were recruited just prior to elective cesarean section. Peripheral blood samples were taken from these subjects just prior to delivery and at 2 hours post-delivery. In the third part of the study, two patient groups were studied: (a) 12 preeclamptic women and (b) 10 control pregnancies. The median gestational ages of the preeclamptic and control groups were 37 weeks and 38 weeks, respectively. Preeclampsia was defined on the basis of a sustained increase in diastolic blood pressur...

example 2

Detection of hPL and hCG-β mRNA in the Plasma of Pregnant Women

A. Methods

Subjects

[0078]15-ml blood samples were collected with informed consent and Research Ethics Committee approval from healthy women with singleton uncomplicated pregnancies, who attended the Department of Obstetrics and Gynecology at the Prince of Wales Hospital, Hong Kong.

Processing of Blood Samples

[0079]The blood samples were collected in EDTA-containing and plain tubes, and centrifuged at 1600×g for 10 min at 4° C. Plasma and serum were then carefully transferred into plain polypropylene tubes. The serum samples were stored at −20° C. for immunoassays for the hPL and hCG-β proteins. The plasma samples were re-centrifuged at 16000×g for 10 min at 4° C., and the supernatants were collected into fresh polypropylene tubes. All placental tissue samples were immediately stored in an RNA Later stabilizing solution (Ambion, Austin, Tex.) and kept at −80° C. until RNA extraction. For the filtration study, plasma samples...

example 3

Elevation in Maternal Plasma GAPDH mRNA in Preeclamptic Women

[0091]Pregnant women attending the Department of Obstetrics and Gynecology at the Prince of Wales Hospital were recruited with informed consent. Preeclampsia was diagnosed using the criteria as indicated in Example 1.

A. Methods

[0092]Maternal blood samples were taken into heparinized tubes and processed as indicated in Example 1. Plasma RNA was extracted and GAPDH mRNA level was quantified as indicated in Example 1.

B. Results

[0093]Elevation in maternal plasma GAPDH mRNA concentrations was observed in the preeclamptic group, when compared with the control group (FIG. 5). The median maternal plasma GAPDH mRNA concentrations in control and preeclamptic subjects were 70 pg / ml and 281 pg / ml, respectively. The difference is statistically significant (Mann-Whitney test, p<0.005).

C. Conclusion

[0094]Maternal plasma GAPDH mRNA is a new noninvasive marker for preeclampsia.

CROSS REFERENCE TO RELATED APPLICATIONS

[0001] This application is a divisional of U.S. application Ser. No. 10 / 759,783, filed Jan. 16, 2004. This application also claims priority to U.S. Provisional Application No. 60 / 440,906, filed Jan. 17, 2003, the contents of both are incorporated herein by reference in their entirety.BACKGROUND OF THE INVENTION

[0002] Prenatal diagnosis has been routinely conducted using cells isolated from the fetus through procedures such as chorionic villus sampling (CVS) or amniocentesis. These conventional methods are, however, invasive and present an appreciable risk to both the mother and the fetus despite most careful handling (Tabor et al., Lancet 1:1287-1293, 1986).

[0003] Alternatives to these invasive approaches have been developed for prenatal screening, e.g., to detecting fetal abnormalities, following the discoveries that several types of fetal cells can be found in maternal circulation (Johansen et al., Prenat. Diagn. 15:921-931, 1995) and more impor...

Examples

example 1

Elevated hCRH MRNA Level in Preeclamptic Women

A. Methods

Subjects

[0065]Peripheral blood samples were collected with informed consent and Research Ethics Committee approval from pregnant women, who attended the Department of Obstetrics and Gynecology at the Prince of Wales Hospital, Hong Kong.

[0066]In the first part of this study, blood samples were obtained from 10 healthy pregnant women during the third trimester of gestation. In the second part of the project, 4 pregnant women with uncomplicated pregnancy were recruited just prior to elective cesarean section. Peripheral blood samples were taken from these subjects just prior to delivery and at 2 hours post-delivery. In the third part of the study, two patient groups were studied: (a) 12 preeclamptic women and (b) 10 control pregnancies. The median gestational ages of the preeclamptic and control groups were 37 weeks and 38 weeks, respectively. Preeclampsia was defined on the basis of a sustained increase in diastolic blood pressur...

example 2

Detection of hPL and hCG-β mRNA in the Plasma of Pregnant Women

A. Methods

Subjects

[0078]15-ml blood samples were collected with informed consent and Research Ethics Committee approval from healthy women with singleton uncomplicated pregnancies, who attended the Department of Obstetrics and Gynecology at the Prince of Wales Hospital, Hong Kong.

Processing of Blood Samples

[0079]The blood samples were collected in EDTA-containing and plain tubes, and centrifuged at 1600×g for 10 min at 4° C. Plasma and serum were then carefully transferred into plain polypropylene tubes. The serum samples were stored at −20° C. for immunoassays for the hPL and hCG-β proteins. The plasma samples were re-centrifuged at 16000×g for 10 min at 4° C., and the supernatants were collected into fresh polypropylene tubes. All placental tissue samples were immediately stored in an RNA Later stabilizing solution (Ambion, Austin, Tex.) and kept at −80° C. until RNA extraction. For the filtration study, plasma samples...

example 3

Elevation in Maternal Plasma GAPDH mRNA in Preeclamptic Women

[0091]Pregnant women attending the Department of Obstetrics and Gynecology at the Prince of Wales Hospital were recruited with informed consent. Preeclampsia was diagnosed using the criteria as indicated in Example 1.

A. Methods

[0092]Maternal blood samples were taken into heparinized tubes and processed as indicated in Example 1. Plasma RNA was extracted and GAPDH mRNA level was quantified as indicated in Example 1.

B. Results

[0093]Elevation in maternal plasma GAPDH mRNA concentrations was observed in the preeclamptic group, when compared with the control group (FIG. 5). The median maternal plasma GAPDH mRNA concentrations in control and preeclamptic subjects were 70 pg / ml and 281 pg / ml, respectively. The difference is statistically significant (Mann-Whitney test, p<0.005).

C. Conclusion

[0094]Maternal plasma GAPDH mRNA is a new noninvasive marker for preeclampsia.

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