Devices And Methods For Detecting Amniotic Fluid In Vaginal Secretions

Abstract

The present invention relates to a diagnostic method for the detection of small quantities of amniotic fluid in the vagina. More specifically, the invention relates to the detection of PAMG-1 in the vagina using anti-PAMG-1 antibodies.

1 . A method for diagnosing rupture of fetal membranes (ROM) with 100% negative predictive value in a pregnant woman, the method comprising:
 (a) contacting a vaginal fluid sample obtained from the pregnant woman with a first and a second monoclonal antibody that do not cross-react with each other and which are each specific for the same amniotic protein, wherein at least one of the two monoclonal antibodies binds to the amniotic protein when present in the sample to form an amniotic protein/monoclonal antibody complex;   (b) detecting the presence of the amniotic protein/monoclonal antibody complex in the sample, only when the concentration of the amniotic protein in the sample exceeds a predefined detection threshold, wherein the predefined detection threshold is set at a level that eliminates 100% of false positive results; and   (c) diagnosing ROM with 100% negative predictive value if the amniotic protein is detected in the sample.   
     
     
         2 . The method of  claim 1 , wherein the predefined detection threshold is an amount greater than the regular background level of the amniotic protein in vaginal secretions of pregnant women in the absence of ROM and less than the level of the amniotic protein present in amniotic fluid. 
     
     
         3 . The method of  claim 1 , wherein the first and second monoclonal antibodies have different binding affinities for the amniotic protein. 
     
     
         4 . The method of  claim 1 , further comprising diagnosing rupture of fetal membrane with at least 99% specificity and 100% sensitivity. 
     
     
         5 . The method of  claim 1 , further comprising diagnosing rupture of fetal membrane with 99% positive predictive value. 
     
     
         6 . The method of  claim 1 , wherein the pregnant woman is at 20 to 41 weeks gestation. 
     
     
         7 . The method of  claim 1 , wherein the amniotic protein is placental α 1 -microglobulin (PAMG-1). 
     
     
         8 . The method of  claim 1 ; wherein the predefined detection threshold is 5 ng/ml. 
     
     
         9 . The method of  claim 7 ; wherein the predefined detection threshold is 5 ng/ml. 
     
     
         10 . The method of  claim 7 , wherein the first and second PAMG-1-specific monoclonal antibodies are selected from the group consisting of M271, produced by hybridoma N271, deposited with the Russian National Collection of Industrial Microorganisms (VKPM) Depository and assigned accession number VKPM-93; M52, produced by hybridoma N52, deposited with the VKPM and assigned accession number VKPM-92; and M42, produced by hybridoma N42, deposited with the VKPM and assigned accession number VKPM-94. 
     
     
         11 . A method for diagnosing rupture of fetal membranes (ROM) with at least 99% positive predictive value in a pregnant woman, the method comprising:
 (a) contacting a vaginal fluid sample obtained from the pregnant woman with a first and a second monoclonal antibody that do not cross-react with each other and which are each specific for the same amniotic protein, wherein at least one of the two monoclonal antibodies binds to the amniotic protein when present in the sample to form an amniotic protein/monoclonal antibody complex;   (b) detecting the presence of the amniotic protein/monoclonal antibody complex in the sample, only when the concentration of the amniotic protein in the sample exceeds a predefined detection threshold that is set at a level that reduces false positive results such that at least 99% positive predictive value is achieved; and   (c) diagnosing ROM with at least 99% positive predictive value if the amniotic protein is detected in the sample.   
     
     
         12 . The method of  claim 11 , wherein the predefined detection threshold is an amount greater than the regular background level of the amniotic protein in vaginal secretions of pregnant women in the absence of ROM and less than the level of the amniotic protein present in amniotic fluid. 
     
     
         13 . The method of  claim 11 , wherein the first and second monoclonal antibodies have different binding affinities for the amniotic protein. 
     
     
         14 . The method of  claim 11 , further comprising diagnosing rupture of fetal membrane with at least 99% specificity and 100% sensitivity. 
     
     
         15 . The method of  claim 11 , wherein the pregnant woman is at 20 to 41 weeks gestation. 
     
     
         16 . The method of  claim 11 , wherein the amniotic protein is placental α 1 -microglobulin (PAMG-1). 
     
     
         17 . The method of  claim 16 ; wherein the predefined detection threshold is 5 ng/ml. 
     
     
         18 . The method of  claim 16 , wherein the first and second PAMG-1-specific monoclonal antibodies are selected from the group consisting of M271, produced by hybridoma N271, deposited with the Russian National Collection of Industrial Microorganisms (VKPM) Depository and assigned accession number VKPM-93; M52, produced by hybridoma N52, deposited with the VKPM and assigned accession number VKPM-92; and M42, produced by hybridoma N42, deposited with the VKPM and assigned accession number VKPM-94. 
     
     
         19 . A method for diagnosing rupture of fetal membranes (ROM) in a pregnant woman with at least 99% specificity and 100% sensitivity, the method comprising:
 a) contacting a vaginal fluid sample obtained from the pregnant woman with a first and a second monoclonal antibody that do not cross-react with each other and which are each specific for the same amniotic protein, wherein at least one of the two monoclonal antibodies binds to the amniotic protein when present in the sample to form an amniotic protein/monoclonal antibody complex;   (b) detecting the presence of the amniotic protein/monoclonal antibody complex in the sample, only when the concentration of the amniotic protein in the sample exceeds a predefined detection threshold; and   (c) diagnosing ROM with at least 99% specificity and 100% sensitivity if the amniotic protein is detected in the sample.   
     
     
         20 . (canceled)