After identifying several biomarkers for prenatal infection, the founders of ProteoGenix now plan to make a non-invasive amniochip that could be used to screen pregnant women for a wide range of prenatal defects, including birth defects and fetal growth restriction.
With the new amniochip, the company hopes to be able to identify prenatal infections early by simply taking a blood sample from the mother and running the processed sample through a mass spectrometer.
“The goal is to avoid invasive procedure and to come up with the next generation of pregnancy screening,” said Chief Operating Officer Srinivasa Nagalla, who oversees most of the biotechnology aspects of the company, including the mass spectrometry and chip development techniques. “A lot of things change in pregnancy and a lot of this new [proteomics] technology can be a good way to monitor several changes at the same time.”
Nagalla said he expects the amniochip to be available for testing in clinical trials next year. If clinical trials go well, the company will then file for approval from the US Food and Drug Administration.
In the July 28 issue of the Journal of the American Medical Association, Nagalla and collaborator Michael Gravett, the chief of maternal-fetal medicine at Oregon Health & Science University, reported that they found three biomarkers whose presence indicates that a mother has a greater than 80 percent risk of an amniotic infection.
The biomarkers, called Calgranulins A, B, and C, were chosen out of 12 prenatal infection biomarkers as being the most sensitive. In their clincal study, researchers identified all of the proteins expressed in samples of amniotic fluid taken from 36 women, then used mass spectrometry and data bank analysis to pick out a subset of proteins that were clearly different between mothers with infections and mothers without infections.
The researchers compared their mass spectrometry results to results from a standard bacterial culture test and found that all positive and negative results matched between the two methods.
“The likely outcome of this finding is that a simple test may be developed to detect the presence of these biomarkers, thereby signaling the pregnant woman has an infection and needs treatment,” said Nagalla.
Uterine infections during pregnancy typically arise from an overgrowth of bacteria that normally live in the vagina. Sometimes the bacteria cause no symptoms until the mother goes into labor prematurely. Currently, prenatal infections are detected using a standard bacterial culture test in which amniotic fluid is plated out and allowed to grow for two to three days.
Gravett and Nagalla hope that their new test will enable mothers to be tested using a non-invasive procedure as soon as they show some sign of clinical infection, such as fever. With proper intervention, pre-term delivery — a major cause of newborn deaths — may be prevented.
More than 10 percent of births in the United States are premature, according to the American College of Obstetricians and Gynecologists. Premature births are responsible for 60 to 80 percent of newborn deaths.
In addition to identifying protein biomarkers for intra-amniotic infections, Gravett and his team also tested the length of time between infection and the appearance of biomarkers using non-human primates.
“Biomarkers for infection were detected in a very short amount of time —within only 12 hours of infection,” Nagalla said.
All products produced by ProteoGenix, a privately funded com pany founded in 2002, are pregnancy related, said Nagalla. The company has begun working to develop diagnostics for birth defects, including neural tube defects and chromosomal abnormalities, such as in Down syndrome. It has also been working on biomarkers for growth restriction or maturation and other aspects of pregnancy such as preeclampsia, a prental condition characterized by high blood pressure.
“The goal is to develop a multi-analyzer assay that will have a very high-throughput application,” said Nagalla. “We can try to analyze 10, 20, 30, 40 biomarkers at the same time with one screening.”
Following the identification of proteins in the amniotic fluid of both humans and a non-human primate species, the company is mining the protiens to find what is relevant to diagnostics, Nagalla added.
Nagalla said the researchers are currently looking at three different sites to do prospective clinical trials of the amniochip.
—TSL