Biomarker and method for evaluating maternal premature delivery risk in early pregnancy and application

Abstract

The invention discloses a biomarker and a method for evaluating the premature delivery risk of a maternal body at the early pregnancy stage and application of the biomarker, the biomarker is a combination of four microorganisms in intestinal flora, and the four microorganisms are respectively a clostridium-free clostridium strain, an uncertain algal strain, a mucous eubacterium strain CAG: 257 (Blauria sp. CAG: 257) and an eubacterium strain CAG: 251 (Eubacterium sp. CAG: 251). The invention further discloses a method for evaluating the premature delivery risk of the maternal body at the early pregnancy stage. The flora risk score is determined based on the relative abundance information of the various microorganisms in the individual, and the premature delivery risk of the individual can be evaluated in the early pregnancy stage.

Description

Technical Field

[0001] This invention relates to the field of precision medicine for the purpose of predicting the risk of preterm birth in early pregnancy, and in particular to a biomarker, method and use for assessing the risk of maternal preterm birth in early pregnancy. Background Technology

[0002] Preterm birth, generally defined as delivery before 37 weeks of gestation, is the leading cause of neonatal and under-five mortality worldwide. According to the World Health Organization (WHO), approximately 15 million premature infants are born globally each year, accounting for nearly 10% of all newborns. Preterm birth not only increases the risk of neonatal death, but even if the infant survives, they may face a range of long-term health problems, including but not limited to respiratory illnesses, neurodevelopmental disorders, visual and hearing impairments, learning disabilities, and psychological and behavioral issues. The mechanisms underlying preterm birth are complex, involving multiple factors such as genetics, environment, immunity, endocrine function, infection, and maternal lifestyle. Despite significant advancements in medical technology in recent years, our understanding of the molecular mechanisms maintaining full-term pregnancies remains limited. Further systematic and multi-dimensional research is urgently needed to elucidate the underlying biological mechanisms and provide a scientific basis for the prevention and intervention of preterm birth.

[0003] Childbirth is a highly coordinated, multifactorial physiological process, regulated in part by maternal genetic background and environmental exposures during pregnancy. In recent years, increasing research has shown that the maternal microbiome, particularly the gut and vaginal microbiome, acts as a "biosensor" of external environmental exposure, playing a crucial role in metabolic remodeling, immune homeostasis regulation, and the physiological balance of the maternal-fetal interface during pregnancy. Existing studies have indicated a close association between vaginal flora imbalance and preterm birth; for example, bacterial vaginosis not only alters the composition of the vaginal microecology but also significantly increases the risk of preterm birth. Regarding the gut microbiome, although a few studies have suggested differences in species abundance between the gut microbiota of preterm mothers and those who deliver at term, limitations such as inconsistent sample collection times, small sample sizes, and high population heterogeneity in study design have resulted in a lack of consistent and statistically significant conclusions. Therefore, the mechanisms by which the maternal gut microbiome plays a role in preterm birth require further systematic and in-depth exploration.

[0004] Currently, clinical prediction of preterm birth risk mainly relies on a comprehensive assessment of maternal serum metabolites, inflammatory factors, clinical indicators, and past obstetric history. However, these methods are often limited by issues such as invasive sampling, high costs, or late predictive windows, making it difficult to achieve non-invasive and efficient preterm birth risk identification in early pregnancy. In recent years, with the development of metagenomics and multi-omics technologies, the maternal gut microbiome is gradually becoming a new hotspot in preterm birth prediction research due to its advantages such as easy access, dynamic monitoring, and close correlation with host immune metabolism. Preliminary studies have found that changes in the abundance of certain gut microbiota (such as butyric acid-producing bacteria and bifidobacteria) may be significantly correlated with preterm birth risk, suggesting their potential value in preterm birth prediction.

[0005] Therefore, constructing a preterm birth risk prediction model based on the maternal gut microbiome holds promise for early identification of high-risk pregnant women through non-invasive stool sample collection in early pregnancy. This microbiome-based prediction strategy will provide clinicians with a non-invasive, cost-effective, and highly translational tool. Furthermore, after identifying high-risk individuals, early lifestyle modifications, probiotic supplementation, or dietary interventions can be used to reshape the maternal gut microbiota, thereby reducing the risk of preterm birth and providing new ideas and methods for achieving precision prevention and individualized obstetric management. Summary of the Invention

[0006] The purpose of this invention is to address the shortcomings of existing technologies by providing a biomarker, method, and application for assessing maternal preterm birth risk in early pregnancy. This invention assesses maternal preterm birth risk based on gut microbiota characteristics, guiding the host to improve their diet and lifestyle to achieve better delivery outcomes. Specifically, this invention uses a simple calculation and scoring based on the relative abundance of four gut microbial species to assess maternal preterm birth risk in early pregnancy. Furthermore, this scoring has been demonstrated to be validated in independent pregnant women populations, indicating that the method of this invention has extrapolability and universality, and can be widely applied to assess maternal preterm birth risk in early pregnancy, thereby helping individuals choose or adjust their lifestyle, supplement with probiotics, or intervene in their diet.

[0007] The technical solution adopted in this invention is as follows:

[0008] Biomarkers used to assess the risk of preterm birth in early pregnancy are combinations of the following four microorganisms in the gut microbiota:

[0009] Harmless Clostridium innocuum, Alistipes indistinctus, Blautia sp. CAG:257, and Eubacterium sp. CAG:251.

[0010] Based on the relative abundance of various microorganisms in the biomarkers of individual i, the microbial community risk score (MRS) is calculated using the following formula. i :

[0011]

[0012] Among them, M ij The relative abundance of the CLR (center-log ratio) transformed for the marker of the j-th species in the i-th individual. S represents the set of biomarkers, and j ranges from 1 to 4, i.e., S = 4;

[0013] According to the microbial community risk score MRS i To determine the risk of preterm birth in individual i during early pregnancy.

[0014] If MRS i An MRS score ≥1 indicates a high risk of premature birth; if 0 ≤ MRS, the individual is considered a high-risk individual for premature birth. i If <1, the individual is classified as low to medium risk; if MRS i If the value is less than 0, the individual is considered a low-risk premature birth.

[0015] The present invention also provides the use of a product for detecting said biomarker in the preparation of a kit for assessing the risk of preterm birth in early pregnancy, comprising:

[0016] 1) Collect samples from the subjects to be tested;

[0017] 2) Determine the relative abundance information of each of the above biomarkers in the sample obtained in 1);

[0018] 3) Sum the relative abundance information of the four biomarkers obtained, and compare the sum with a preset threshold to determine the risk of preterm birth in the early stages of pregnancy.

[0019] In this scheme, the preset thresholds are 1 and 0; when the sum is ≥1, the individual is determined to be at high risk of premature birth; when the sum is ≥0 and <1, the individual is determined to be at medium or low risk; when the sum is <0, the individual is determined to be at low risk of premature birth.

[0020] Furthermore, the sample is a fecal sample from the subject.

[0021] The present invention also provides a product for assessing the risk of premature birth in early pregnancy. The product is used to detect the relative abundance information of four microorganisms in the mother's fecal sample, sum them and compare them with a preset threshold, and output the risk of premature birth. The four microorganisms are: harmless Clostridium innocuum, indeterminate Alistipes indistinctus, Blautia sp. CAG:257, and Eubacterium sp. CAG:251.

[0022] In this scheme, the preset threshold is 1. When the summation result is ≥1, the mother is output as having a high risk of premature birth.

[0023] When a high risk of premature birth is identified, it may be recommended that the subject improve their gut microbiota and lifestyle to prevent premature birth.

[0024] The beneficial effects of this invention are as follows:

[0025] This invention identifies a set of highly efficient and identifiable biomarkers by studying the maternal gut microbiota associated with the risk of preterm birth in early pregnancy. These biomarkers can be used to assess the maternal risk of preterm birth and guide the host to improve reproductive health by adjusting lifestyle and diet. The biomarkers involved can detect the risk of preterm birth in a non-invasive, rapid, and convenient manner, thereby effectively guiding the adjustment of the maternal lifestyle and diet. Attached Figure Description

[0026] Figure 1 This figure shows the validation results of the association between the gut microbiota score constructed in this invention and preterm birth in the discovery cohort and a completely independent cohort. The horizontal axis in the figure represents the odds ratio (OR) of the constructed gut microbiota score for preterm birth, and the error bar represents the 95% confidence interval (CI). The data show that in both independent cohorts, the constructed gut microbiota score was associated with a higher risk of preterm birth. Data were obtained from a discovery cohort of 4,286 pregnant women from China and a validation cohort of 1,027 women. After initial data collection, all participants underwent longitudinal follow-up assessments throughout pregnancy, tracking them until delivery. Detailed Implementation

[0027] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0028] This invention addresses the problem of maternal preterm birth risk assessment based on gut microbiota by conducting the following experiments:

[0029] 1. The study included 4,286 pregnant Chinese women. Samples were collected during early pregnancy, and gestational age and case information were subsequently tracked. The trial protocol is attached. Figure 1 .

[0030] 2. Fecal samples were collected in early pregnancy (mean gestational age 10.4 ± 2.0 weeks) for gut microbiome metagenomic sequencing to obtain information on the species composition of the gut microbiota;

[0031] 3. Gestational age (in weeks) is extracted from medical records, initially calculated based on the last menstrual period and corrected for by early pregnancy ultrasound measurements. Preterm birth is defined as delivery before 37 weeks of gestation.

[0032] 4. The relative abundance information of gut microbiota species after CLR (central logarithmic ratio) transformation was used to perform logistic regression analysis with preterm birth to obtain the correlation results between gut microbiota species and preterm birth and the corresponding P-values.

[0033] 5. Based on the association analysis results of early pregnancy gut microbiota and preterm birth obtained in step 4, a gut microbiota risk score was constructed. The specific steps are as follows:

[0034] The Pruning+Thresholding method was used to determine the final gut microbiota characteristics to be included, and only microbial species positively correlated with preterm birth were included. The P-value range was set to {0.5, 0.4, 0.3, 0.2, 0.1, 0.05, 0.04, 0.03, 0.02, 0.01, 0.001, 0.0001}. Microbial species meeting the criteria were selected within each P-value range. A gut microbiota risk score was calculated using the selected species, and the relationship between this risk score and preterm birth was analyzed.

[0035] By comparing the variance explained by the gut microbiota risk scores corresponding to different P-values ​​for preterm birth (R0), 2 ), select R 2 The p-value at which the maximum value is reached is used as the optimal threshold. The results show that when the p-value is 0.01, the explained variance (R²) is significantly reduced. 2 The microbial species included at this time are: harmless Clostridium innocuum, Alistipes indistinctus, Blautia sp. CAG:257 and Eubacterium sp. CAG:251.

[0036] The final microbial community risk score MRSi was determined:

[0037]

[0038] Among them, M ij The relative abundance of the CLR (center log ratio) of the marker of the i-th individual and the j-th species is denoted as S, which represents the set of microorganisms obtained by screening by the p-value, and the value of j ranges from 1 to 4, i.e., S = 4.

[0039] The specific microbial markers mentioned above are:

[0040] Harmless Clostridium innocuum, Alistipes indistinctus, Blautia sp. CAG:257, and Eubacterium sp. CAG:251.

[0041] The established criterion is: if MRS i An MRS score ≥1 indicates a high risk of premature birth; if 0 ≤ MRS, the individual is considered a high-risk individual for premature birth. i If <1, the individual is classified as low to medium risk; if MRS i If the value is less than 0, the individual is considered a low-risk premature birth.

[0042] Using the above scoring method, the gut microbiome was sequenced and analyzed in a completely independent group of pregnant women, and a gut microbiota score (MRS) was constructed based on the relative abundance of the four bacterial species.

[0043] The association between the score and the risk of preterm birth was analyzed in two population cohorts. The results showed that in both the discovery and validation cohorts, the MRS score was significantly positively correlated with the risk of preterm birth, especially in the spontaneous preterm birth subgroup. Compared to individuals with an MRS score less than 0 (low risk), a MRS score ≥ 1 significantly increased the risk of preterm birth in pregnant women. These results demonstrate that the gut microbiota score constructed in this invention effectively assesses the risk of preterm birth in pregnant women in completely independent populations, providing a new biomarker and potential intervention target for gut microbiome-based preterm birth prediction.

[0044] Based on the above research protocol and results, this invention analyzes the composition of the gut microbiota in early pregnancy and combines it with clinical follow-up data to identify microbial characteristics significantly associated with preterm birth, successfully constructing a gut microbiota risk score (MRS) for preterm birth risk assessment. This score, based on the relative abundance of several key bacterial species, can effectively distinguish between high-risk and low-risk pregnant women for preterm birth and has been validated in independent cohorts. This invention provides a quantifiable biomarker system for preterm birth risk prediction based on the gut microbiome, facilitating non-invasive screening and early warning of preterm birth risk during pregnancy, and thus providing a scientific basis for clinical intervention and personalized health management.

Claims

1. A biomarker for assessing maternal preterm birth risk in early pregnancy, characterized in that, It is a combination of the following four microorganisms in the gut microbiota: Harmless Clostridium innocuum, Alistipes indistinctus, Blautia sp. CAG:257, and Eubacterium sp. CAG:

251.

2. A method for assessing the risk of preterm birth in early pregnancy, for non-disease diagnostic purposes, characterized in that... The method includes the following: based on the relative abundance of various microorganisms in the biomarkers as described in claim 1 for individual i, a microbial community risk score (MRS) is calculated using the following formula. i : Among them, M ij The relative abundance of the biomarker for the i-th individual and the j-th species after central log-ratio (CLR) transformation is determined using metagenomic methods. S represents the set of biomarkers, and j ranges from 1 to 4, i.e., S = 4. According to the microbial community risk score MRS i To determine the risk of preterm birth in individual i during early pregnancy.

3. The method for assessing maternal preterm birth risk in early pregnancy according to claim 2, characterized in that, If MRS i ≥1 indicates a high risk of premature birth; if 0≤MRS i If <1, the individual is classified as low to medium risk; if MRS i If the value is less than 0, the individual is considered a low-risk premature birth.

4. The use of the product detecting the biomarker of claim 1 in the preparation of a kit for assessing the risk of preterm birth in early pregnancy, characterized in that, include: 1) Collect samples from the subjects to be tested; 2) Determine the relative abundance information of each biomarker according to claim 1 in the sample obtained in 1); 3) Sum the relative abundance information of the four biomarkers as described in claim 1, and compare the sum with a preset threshold to determine the risk of preterm birth in the early stages of pregnancy for the subject.

5. The use according to claim 4, characterized in that, The preset thresholds are 1 and 0; when the sum is ≥ 1, the individual is determined to be at high risk of premature birth; when the sum is ≥ 0 and < 1, the individual is determined to be at medium to low risk; when the sum is < 0, the individual is determined to be at low risk of premature birth.

6. The use according to claim 4, characterized in that, The sample in question was a fecal sample from the subject.

7. A product for assessing the risk of preterm birth in early pregnancy, characterized in that, The product is used to detect the relative abundance of four microorganisms in the mother's fecal sample, sum them up and compare them with a preset threshold, and output the risk of premature birth in the mother. The four microorganisms are: harmless Clostridium innocuum, indeterminate Alistipes indistinctus, Blautia sp. CAG:257, and Eubacterium sp. CAG:

251.

8. The product according to claim 7, characterized in that, The preset threshold is 1. When the summation result is ≥1, the mother is output as having a high risk of premature birth.

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