Monitoring Laboratory Occupational Exposures to Burkholderia pseudomallei.

Background: Burkholderia pseudomallei is a Tier 1 overlap select agent and subject to the select agent regulations (42 CFR §73 and 9 CFR §121). It is a gram-negative, motile, soil saprophyte, and the etiologic agent of melioidosis. B. pseudomallei infection can produce systemic illness and can be fatal in the absence of appropriate treatment. Laboratory exposures involving this organism may occur when appropriate containment measures are not employed. Current disease treatment inadequacies and the risk factors associated with melioidosis make this an agent of primary concern in research, commercial, and clinical laboratory environments. Results: This study presents data reported to Centers for Disease Control and Prevention (CDC), Division of Select Agents and Toxins for releases involving B. pseudomallei in 2017-2019 that occurred in Biosafety Level (BSL)-2 and BSL-3 laboratories. Fifty-one Animal and Plant Health Inspection Service (APHIS)/CDC Form 3 release reports led to the medical surveillance of 275 individuals. Entities offered post-exposure prophylaxis to ∼76% of the individuals impacted in the presented events. Summary: Laboratory safety can be improved by implementing appropriate safety precautions to minimize exposures. Most of the incidents discussed in this evidence-based report occurred during work conducted in the absence of primary containment. None of the releases resulted in illness, death, or transmission to or among workers, nor was there transmission outside of a laboratory into the surrounding environment or community. Effective risk assessment and management strategies coupled with standard and special microbiological policies and procedures can result in reduced exposures and improved safety at facilities.

The pattern and magnitude of "in vivo thrombin generation" differ in women with preeclampsia and in those with SGA fetuses without preeclampsia.

OBJECTIVE: We aimed to determine the differences in the pattern and magnitude of thrombin generation between patients with preeclampsia (PE) and those with a small-for-gestational-age (SGA) fetus. METHODS: This cross-sectional study included women in the following groups: (1) normal pregnancy (NP) (n = 49); (2) PE (n = 56); and (3) SGA (n = 28). Maternal plasma thrombin generation (TGA) was measured, calculating: (a) lag time (LT); (b) velocity index (VI); (c) peak thrombin concentration (PTC); (d) time-to-peak thrombin concentration (TPTC); and (e) endogenous thrombin potential (ETP). RESULTS: (1) The median TPTC, VI, and ETP differed among the groups (p = .001, p = .006, p < .0001); 2) the median ETP was higher in the PE than in the NP (p < .0001) and SGA (p = .02) groups; 3) patients with SGA had a shorter median TPTC and a higher median VI than the NP (p = .002, p = .012) and PE (p < .0001, p = .006) groups. CONCLUSIONS: (1) Patients with PE had higher in vivo thrombin generation than women with NP and those with an SGA fetus; (2) the difference in TGA patterns between PE and SGA suggests that the latter group had faster TGA, while patients with PE had a longer reaction, generating more thrombin. This observation is important for the identification of a subset of patients who might benefit from low molecular-weight heparin.

The impact of regulations, safety considerations and physical limitations on research progress at maximum biocontainment.

We describe herein, limitations on research at biosafety level 4 (BSL-4) containment laboratories, with regard to biosecurity regulations, safety considerations, research space limitations, and physical constraints in executing experimental procedures. These limitations can severely impact the number of collaborations and size of research projects investigating microbial pathogens of biodefense concern. Acquisition, use, storage, and transfer of biological select agents and toxins (BSAT) are highly regulated due to their potential to pose a severe threat to public health and safety. All federal, state, city, and local regulations must be followed to obtain and maintain registration for the institution to conduct research involving BSAT. These include initial screening and continuous monitoring of personnel, controlled access to containment laboratories, accurate and current BSAT inventory records. Safety considerations are paramount in BSL-4 containment laboratories while considering the types of research tools, workflow and time required for conducting both in vivo and in vitro experiments in limited space. Required use of a positive-pressure encapsulating suit imposes tremendous physical limitations on the researcher. Successful mitigation of these constraints requires additional time, effort, good communication, and creative solutions. Test and evaluation of novel vaccines and therapeutics conducted under good laboratory practice (GLP) conditions for FDA approval are prioritized and frequently share the same physical space with important ongoing basic research studies. The possibilities and limitations of biomedical research involving microbial pathogens of biodefense concern in BSL-4 containment laboratories are explored in this review.

The transcriptome of the fetal inflammatory response syndrome.

PROBLEM: The fetal inflammatory response syndrome (FIRS) is considered the counterpart of the systemic inflammatory response syndrome (SIRS), but similarities in their regulatory mechanisms are unclear. This study characterizes the fetal mRNA transcriptome of peripheral leukocytes to identify key biological processes and pathways involved in FIRS. METHOD OF STUDY: Umbilical cord blood from preterm neonates with FIRS (funisitis, plasma IL-6 >11 pg/mL; n = 10) and neonates with no evidence of inflammation (n = 10) was collected at birth. Results Microarray analysis of leukocyte RNA revealed differential expression of 541 unique genes, changes confirmed by qRT-PCR for 41 or 44 genes tested. Similar to SIRS and sepsis, ontological and pathway analyses yielded significant enrichment of biological processes including antigen processing and presentation, immune response, and processes critical to cellular metabolism. RESULTS: are comparable with microarray studies of endotoxin challenge models and pediatric sepsis, identifying 25 genes across all studies. CONCLUSION: This study is the first to profile genome-wide expression in FIRS, which demonstrates a substantial degree of similarity with SIRS despite differences in fetal and adult immune systems.

Could alterations in maternal plasma visfatin concentration participate in the phenotype definition of preeclampsia and SGA?

OBJECTIVE: Women with preeclampsia and those who delivered a small-for-gestational-age (SGA) neonate share several mechanisms of disease, including chronic uteroplacental ischemia and failure of physiologic transformation of the spiral arteries. However, the clinical manifestation of these obstetrical syndromes is remarkably different. It has been proposed that an altered maternal metabolic state, as well as a unique circulating cytokines milieu, predispose women to develop either preeclampsia or SGA. Compelling evidence suggests that adipose tissue orchestrates both metabolic pathways and immunological responses via the production of adipokines. Visfatin is a novel adipocytokine with metabolic and immunomodulating properties. The objective of this study was to determine whether preeclampsia and SGA are associated with alterations in maternal circulating visfatin concentrations. METHODS: This cross-sectional study included pregnant women in the following groups: (1) normal pregnancy (n = 158); (2) patients with preeclampsia (n = 43) of which 32 had an AGA and 11 had an SGA neonate; (3) patients without preeclampsia who delivered an SGA neonate (n = 55). Maternal plasma visfatin concentrations were measured by ELISA. Nonparametric tests and multiple linear regression analysis were used. RESULTS: (1) Women who delivered an SGA neonate had a higher median maternal plasma visfatin concentration than those with a normal pregnancy (20.0 ng/ml, interquartile range: 17.2-24.6 vs. 15.2 ng/ml, 12.1-19.2, respectively; P < 0.001) and than those with preeclampsia (14.5 ng/ml, 12.5-18.7; P < 0.001); (2) the median maternal plasma visfatin concentration did not differ significantly between patients with preeclampsia and those with a normal pregnancy (P = 0.8); (3) among patients with preeclampsia, there was no significant difference in the median maternal plasma visfatin concentration between those with or without an SGA neonate (P = 0.5); (4) in a linear regression model, delivery of an SGA neonate and pregestational body mass index were independently associated with increased visfatin concentration after adjustment for confounding factors (maternal age, smoking, gestational age at blood collection and the presence of preeclampsia or SGA). CONCLUSION: (1) Patients with SGA, but not those with preeclampsia, had a higher maternal plasma visfatin concentration than those with a normal pregnancy; (2) this finding suggests differential involvement of visfatin in SGA and preeclampsia; (3) we propose that changes in circulating maternal visfatin concentration may be implicated in the phenotypic definitions and distinction of preeclampsia and SGA.

Changes in amniotic fluid concentration of thrombin-antithrombin III complexes in patients with preterm labor: evidence of an increased thrombin generation.

OBJECTIVE: Preterm labor is associated with excessive maternal thrombin generation, as evidenced by increased circulating thrombin-antithrombin (TAT) III complexes concentration. In addition to its hemostatic functions, thrombin has uterotonic properties that may participate in the mechanism leading to preterm birth in cases of intrauterine bleeding. Thrombin also has a proinflammatory role, and inflammation is associated with increased thrombin generation. The aim of this study was to determine whether intra-amniotic infection/inflammation (IAI) is associated with increased amniotic fluid (AF) thrombin generation in women with preterm and term deliveries. STUDY DESIGN: This cross-sectional study included the following groups: (1) mid-trimester (n = 74); (2) term not in labor (n = 39); (3) term in labor (n = 25); (4) term in labor with IAI (n = 22); (5) spontaneous preterm labor (PTL) who delivered at term (n = 62); (6) PTL without IAI who delivered preterm (n = 59); (7) PTL with IAI (n = 71). The AF TAT III complexes concentration was measured by enzyme linked immunosorbent assay (ELISA). Non-parametric statistics were used for analysis. RESULTS: (1) TAT III complexes were identified in all AF samples; (2) patients with PTL who delivered preterm, with and without IAI, had a higher median AF TAT III complexes concentration than those with an episode of PTL who delivered at term (p < 0.001, p = 0.03, respectively); (3) among patients with PTL without IAI, elevated AF TAT III complexes concentration were independently associated with a shorter amniocentesis-to-delivery interval (hazard ratio, 1.5; 95% CI, 1.07-2.1); (4) among patients at term, those with IAI had a higher median AF TAT III complexes concentration than those without IAI, whether in labor or not in labor (p = 0.02); (5) there was no significant difference between the median AF TAT III complexes concentration of patients at term with and without labor; (6) patients who had a mid-trimester amniocentesis had a lower median AF TAT III complexes concentration than that of patients at term not in labor (p < 0.001). CONCLUSIONS: We present herein a distinct difference in the pattern of intra-amniotic thrombin generation between term and preterm parturition. PTL leading to preterm delivery is associated with an increased intra-amniotic thrombin generation regardless of the presence of IAI. In contrast, term delivery is associated with an increased intra-amniotic thrombin generation only in patients with IAI.

A prospective cohort study of the value of maternal plasma concentrations of angiogenic and anti-angiogenic factors in early pregnancy and midtrimester in the identification of patients destined to develop preeclampsia.

OBJECTIVE: Changes in the maternal plasma concentrations of angiogenic (placental growth factor (PlGF) and vascular endothelial growth factor (VEGF)) and anti-angiogenic factors (sEng and vascular endothelial growth factor receptor-1 (sVEGFR-1)) precede the clinical presentation of preeclampsia. This study was conducted to examine the role of maternal plasma PlGF, sEng, and sVEGFR-1 concentrations in early pregnancy and midtrimester in the identification of patients destined to develop preeclampsia. METHODS: This longitudinal cohort study included 1622 consecutive singleton pregnant women. Plasma samples were obtained in early pregnancy (6-15 weeks) and midtrimester (20-25 weeks). Maternal plasma PlGF, sEng, and sVEGFR-1 concentrations were determined using sensitive and specific immunoassays. The primary outcome was the development of preeclampsia. Secondary outcomes included term, preterm, and early-onset preeclampsia. Receiving operating characteristic curves, sensitivity, specificity, positive and negative likelihood ratios, and multivariable logistic regression were applied. A p-value of <0.05 was considered significant. RESULTS: (1) The prevalence of preeclampsia, term, preterm, (<37 weeks) and early-onset preeclampsia (<34 weeks) was 3.8 (62/1622), 2.5 (40/1622), 1.4 (22/1622) and 0.6% (9/1622), respectively; (2) Higher likelihood ratios were provided by ratios of midtrimester plasma concentrations of PlGF, sEng, and sVEGFR-1 than single analytes; (3) Individual angiogenic and anti-angiogenic factors did not perform well in the identification of preeclampsia as a whole; in particular, they perform poorly in the prediction of term preeclampsia; (4) In contrast, a combination of these analytes such as the PlGF/sEng ratio, its delta and slope had the best predictive performance with a sensitivity of 100%, a specificity of 98-99%, and likelihood ratios for a positive test of 57.6, 55.6 and 89.6, respectively, for predicting early-onset preeclampsia. CONCLUSIONS: (1) The PlGF/sEng ratio and its delta and slope had an excellent predictive performance for the prediction of early-onset preeclampsia, with very high likelihood ratios for a positive test result and very low likelihood ratios for a negative test result; and (2) Although the positive likelihood ratios are high and the positive predictive values low, the number of patients needed to be closely followed is 4:1 for the PlGF/sEng ratio and 3:1 for the slope of PlGF/sEng.

Maternal visfatin concentration in normal pregnancy.

OBJECTIVE: Adipose tissue has now emerged as a powerful endocrine organ via the production of adipokines. Visfatin, a novel adipokine with diabetogenic and immuno-modulatory properties has been implicated in the pathophysiology of insulin resistance in patients with obesity and Type-2 diabetes mellitus. The aim of this study was to determine whether there are changes in the maternal plasma concentration of visfatin with advancing gestation and as a function of maternal weight. STUDY DESIGN: In this cross-sectional study, maternal plasma concentrations of visfatin were determined in normal weight and overweight/obese pregnant women in the following gestational age groups: 1) 11-14 weeks (n=52); 2) 19-26 weeks (n=68); 3) 27-34 weeks (n=93); and 4) >37 weeks (n=60). Visfatin concentrations were determined by ELISA. Non parametric statistics were used for analysis. RESULTS: 1) The median maternal plasma visfatin concentration was higher in pregnant women between 19-26 weeks of gestation than that of those between 11-14 weeks of gestation (P<0.01) and those between 27-34 weeks of gestation (P<0.01); 2) among normal weight pregnant women, the median plasma visfatin concentrations of women between 19-26 weeks of gestation was higher than that of those between 11-14 weeks (P<0.01) and those between 27-34 weeks (P<0.01); and 3) among overweight/obese patients, the median maternal visfatin concentration was similar between the different gestational age groups. CONCLUSION: The median maternal plasma concentration of visfatin peaks between 19-26 and has a nadir between 27-34 weeks of gestation. Normal and overweight/obese pregnant women differed in the pattern of changes in circulating visfatin concentrations as a function of gestational age.

Visfatin in human pregnancy: maternal gestational diabetes vis-à-vis neonatal birthweight.

OBJECTIVE: Adipose tissue dysfunction, characterized by dysregulation of adipokines production and/or secretion, has been implicated in the pathophysiology of type-2 diabetes mellitus, a metabolic complication closely related to gestational diabetes mellitus (GDM). Recently, an association between circulating maternal visfatin, a novel adipokine with metabolic and immunoregulatory properties, and impaired glucose metabolism as well as with altered fetal growth, has been proposed. The aims of this study were to determine whether there is an association between maternal plasma visfatin concentration, GDM, and a large-for-gestational-age (LGA) newborn. STUDY DESIGN: This cross-sectional study, included pregnant women at term in the following groups: 1) normal pregnancy and an appropriate-for-gestational-age (AGA) neonate (n=54); 2) normal pregnancy and an LGA newborn (n=47); 3) GDM and an AGA newborn (n=56); 4) GDM and an LGA newborn (n=45). The study population was further stratified by first trimester BMI (<25 vs. > or =25 kg/m(2)). Maternal plasma visfatin concentration was determined by ELISA. Parametric and non-parametric statistics were used for analysis. RESULTS: 1) Among women who delivered an AGA neonate, the median maternal plasma concentration of visfatin was higher in patients with GDM than in those with a normal pregnancy; 2) Among women with a normal pregnancy, those who delivered an LGA neonate had a higher median maternal plasma visfatin concentration than those who delivered an AGA neonate; 3) among patients with normal BMI, there were no significant differences in the median maternal plasma visfatin concentration between the four study groups; and 4) maternal GDM, as well as delivery of an LGA neonate were independently associated with a higher maternal plasma visfatin concentrations. CONCLUSION: The linkage between increased maternal circulating visfatin and the presence of GDM or delivery of an LGA neonate supports the hypothesis that perturbation of adipokines homeostasis may play a role in the pathophysiology of GDM or excess fetal growth.

Resistin in amniotic fluid and its association with intra-amniotic infection and inflammation.

OBJECTIVE: Intra-amniotic infection/inflammation (IAI) is one of the most important mechanisms of disease in preterm birth. Resistin is an adipocytokine that has been linked to insulin resistance, diabetes, obesity and inflammation. The objective of this study was to determine if resistin is present in amniotic fluid (AF) and if its concentration changes with gestational age, in the presence of labour, and in IAI in patients with spontaneous preterm labour (PTL) and intact membranes, preterm prelabour rupture of membranes (PPROM) and clinical chorioamnionitis. STUDY DESIGN: This cross-sectional study included 648 patients in the following groups: (1) women in the mid-trimester of pregnancy (14-18 weeks) who underwent amniocentesis for genetic indications and delivered a normal neonate at term (n = 61); (2) normal pregnant women at term with (n = 49) and without (n = 50) spontaneous labour; (3) patients with an episode of PTL and intact membranes who were classified into: (a) PTL who delivered at term (n = 153); (b) PTL who delivered preterm (<37 weeks gestation) without IAI (n = 108); and (c) PTL with IAI (n = 84); (4) women with PPROM with (n = 47) and without (n = 44) IAI; and (5) patients with clinical chorioamnionitis at term with (n = 22) and without (n = 30) microbial invasion of the amniotic cavity. Resistin concentration in AF was determined by enzyme-linked immunoassay. Non-parametric statistics were used for analyses. RESULTS: (1) Resistin was detected in all AF samples; (2) the median AF resistin concentration at term was significantly higher than in the mid-trimester (23.6 ng/mL vs. 10 ng/mL; p < 0.001); (3) among patients with PTL, the median AF resistin concentration was significantly higher in patients with IAI than in those without IAI (144.9 ng/mL vs. 18.7 ng/mL; p < 0.001) and those with PTL and intact membranes who delivered at term (144.9 ng/mL vs. 16.3 ng/mL; p < 0.001); (4) patients with PPROM with IAI had a significantly higher median AF resistin concentration than those without IAI (132.6 ng/mL vs. 13 ng/mL; p < 0.001); (5) no significant differences were observed in the median AF resistin concentration between patients with spontaneous labour at term and those at term not in labour (28.7 ng/mL vs. 23.6 ng/mL; p = 0.07); and (6) AF resistin concentration > or =37 ng/mL (derived from a receiver-operating characteristic curve) had a sensitivity of 85.4% and a specificity of 94.3% for the diagnosis of intra-amniotic inflammation. CONCLUSIONS: Resistin is a physiologic constituent of the AF, and its concentrations in AF: (1) are significantly elevated in the presence of IAI; (2) increase with advancing gestation; and (3) do not change in the presence of spontaneous labour at term. We propose that resistin may play a role in the innate immune response against intra-amniotic infection.

A role for CXCL13 (BCA-1) in pregnancy and intra-amniotic infection/inflammation.

OBJECTIVES: CXCL13 is a potent chemokine, produced by mature and recently recruited macrophages to sites of inflammation, which has antimicrobial and anti-angiogenic properties. The purpose of this study was to: (1) determine whether CXCL13 is present in maternal serum, umbilical cord blood, and amniotic fluid (AF); (2) to determine if AF concentration changes with intra-amniotic infection/inflammation (IAI); and (3) to localize the production of CXCL13 in chorioamniotic membranes and umbilical cord. STUDY DESIGN: A cross-sectional study on maternal serum was performed including patients in the following groups: (1) non-pregnant women (n = 20), (2) normal pregnant women (n = 49), (3) patients at term not in labor (n = 30), and (4) patients in spontaneous labor at term (n = 29). Umbilical cord blood was collected from term neonates with (n = 30) and without labor (n = 28). Amniotic fluid was obtained from patients in the following groups: (1) midtrimester (n = 65); (2) term not in labor (n = 22); (3) term in labor (n = 47); (4) preterm labor (PTL) with intact membranes leading to term delivery (n = 70); and (5) PTL leading to preterm delivery with IAI (n = 79) and without IAI (n = 60). CXCL13 concentrations were determined by enzyme-linked immunosorbent assay. Chorioamniotic membranes and umbilical cords were examined with immunohistochemistry. Non-parametric statistics were used for analysis. RESULTS: (1) CXCL13 was present in 100% of serum and cord blood samples, and 99% of AF samples (339/343). (2) Serum CXCL13 concentration was significantly higher in pregnant women when compared to non-pregnant women (median 313.3 pg/mL (interquartile range (IQR) 197.2-646.9) vs. 40.5 pg/mL (IQR 29.5-93.5), respectively; p < 0.001). (3) Serum CXCL13 concentration decreased with advancing gestational age (Spearman's Rho = -0.424; p < 0.001). (4) There were no significant differences in the median serum CXCL13 concentration between women at term with and without labor (371.6 pg/mL (IQR 194.3-614.3) vs. 235.1 pg/mL (IQR 182.8-354.7), respectively; p = 0.6). (5) The concentration of CXCL13 in AF did not change with gestational age (p = 0.1). (6) Patients with PTL and delivery with IAI had a significantly higher median concentration of CXCL13 than those without IAI (median 513.2 pg/mL (IQR 199.7-2505.5) vs. 137.3 pg/mL (IQR 96.7-209.6), respectively; p < 0.001) and those who delivered at term (133.7 pg/mL (IQR 97.8-174.8); p < 0.001). (7) Spontaneous labor did not result in a change in the median AF concentration of CXCL13 (labor: 86.9 pg/mL (IQR 55.6-152.0) vs. no labor: 77.8 pg/mL (IQR 68.0-98.0); p = 0.8). (8) CXCL13 was immunolocalized to macrophages in fetal membranes and umbilical vein. CONCLUSIONS: (1) We report for the first time the presence of CXCL13 in AF. (2) AF CXCL13 concentrations are dramatically increased in IAI. (3) Unlike other chemokines, AF and serum CXCL13 concentrations did not change with spontaneous parturition.

CXCL6 (granulocyte chemotactic protein-2): a novel chemokine involved in the innate immune response of the amniotic cavity.

PROBLEM: CXCL6 is a potent pro-inflammatory neutrophil chemoattractant and activator whose activity during pregnancy is not well-established. The purpose of this study was to determine if CXCL6 is present in amniotic fluid (AF) and if CXCL6 concentrations in AF change with labor (pre-term and term) or intra-amniotic infection/inflammation (IAI). METHOD OF STUDY: A cross-sectional study was designed including the following groups: (1) mid-trimester (n = 65); (2) term no labor (n = 20); (3) term labor (n = 44); (4) patients with pre-term labor (PTL) with subsequent term delivery (n = 57); (5) PTL without IAI who delivered pre-term (n = 47); and (6) PTL with IAI (n = 62). AF CXCL6 concentrations were determined by ELISA. RESULTS: CXCL6 was present in all term samples, but undetectable in 64/65 mid-trimester specimens. Patients with PTL and IAI had a significantly higher median AF CXCL6 concentration than those with PTL without IAI [228.9 pg/mL (0.0-8344.8) versus 55.7 pg/mL (0-454.4); P < 0.05] and those with PTL and term delivery [41.5 pg/mL (0-279.0); P < 0.05]. The median AF CXCL6 concentration did not change with spontaneous term labor [term no labor: 81.1 pg/mL (8.5-201.7) versus term labor: 75.2 pg/mL (6.7-378.7): P = 0.7]. CONCLUSION: (1) CXCL6 is detectable in AF and its concentration increases with gestational age; (2) IAI results in increased AF CXCL6 concentrations, suggesting that CXCL6 plays a role in the deployment of an inflammatory response; (3) In contrast to related chemokines, specifically IL-8, AF CXCL6 does not appear to be involved in spontaneous term parturition. These observations are novel, and suggest a role for CXCL6 in the innate immune response to microbial invasion of the amniotic cavity.

Chorioamnionitis and increased galectin-1 expression in PPROM --an anti-inflammatory response in the fetal membranes?

PROBLEM: Galectin-1 can regulate immune responses upon infection and inflammation. We determined galectin-1 expression in the chorioamniotic membranes and its changes during histological chorioamnionitis. METHOD OF STUDY: Chorioamniotic membranes were obtained from women with normal pregnancy (n = 5) and from patients with pre-term pre-labor rupture of the membranes (PPROM) with (n = 8) and without histological chorioamnionitis (n = 8). Galectin-1 mRNA and protein were localized by in situ hybridization and immunohistochemistry. Galectin-1 mRNA expression was also determined by quantitative reverse transcriptase polymerase chain reaction. RESULTS: Galectin-1 mRNA and protein were detected in the amniotic epithelium, chorioamniotic fibroblasts/myofibroblasts and macrophages, chorionic trophoblasts, and decidual stromal cells. In patients with PPROM, galectin-1 mRNA expression in the fetal membranes was higher (2.07-fold, P = 0.002) in those with chorioamnionitis than in those without. Moreover, chorioamionitis was associated with a strong galectin-1 immunostaining in amniotic epithelium, chorioamniotic mesodermal cells, and apoptotic bodies. CONCLUSION: Chorioamnionitis is associated with an increased galectin-1 mRNA expression and strong immunoreactivity of the chorioamniotic membranes; thus, galectin-1 may be involved in the regulation of the inflammatory responses to chorioamniotic infection.

A role for mannose-binding lectin, a component of the innate immune system in pre-eclampsia.

PROBLEM: Mannose-binding lectin (MBL) is a pattern-recognition receptor that activates complement and modulates inflammation. Homozygosity for the most common allele of the MBL2 gene that is associated with high MBL serum concentrations is more prevalent among patients with pre-eclampsia. The objective of this study was to determine maternal plasma MBL concentrations in normal pregnant women and patients with pre-eclampsia. METHOD OF STUDY: This cross-sectional study included normal pregnant women (n = 187) and patients with pre-eclampsia (n = 99). Maternal plasma MBL concentrations were determined by ELISA. RESULTS: Women with pre-eclampsia had a higher median maternal plasma MBL concentration than normal pregnant women. MBL concentration distribution curves were three-modal, the subintervals in normal pregnancy were low (< 143.7), intermediate (143.7-1898.9) and high (> 1898.9 ng/mL). The proportion of normal pregnant women was larger in the low subinterval, while the proportion of patients with preeclampsia was larger in the high subinterval (P = 0.02). Normal pregnant women in the high subinterval had a larger rate of placental underperfusion than those in the low and intermediate subintervals (P = 0.02). CONCLUSIONS: The median maternal plasma MBL concentration is elevated in patients with pre-eclampsia and a larger proportion of these patients are in the high subinterval than normal pregnant women, suggesting that this component of the innate immune system is involved in the mechanisms of disease in pre-eclampsia.

Visfatin/Pre-B cell colony-enhancing factor in amniotic fluid in normal pregnancy, spontaneous labor at term, preterm labor and prelabor rupture of membranes: an association with subclinical intrauterine infection in preterm parturition.

OBJECTIVE: Visfatin, a novel adipokine originally discovered as a pre-B-cell colony enhancing factor, is expressed by amniotic epithelium, cytotrophoblast, and decidua and is over-expressed when fetal membranes are exposed to mechanical stress and/or pro-inflammatory stimuli. Visfatin expression by fetal membranes is dramatically up-regulated after normal spontaneous labor. The aims of this study were to determine if visfatin is detectable in amniotic fluid (AF) and whether its concentration changes with gestational age, spontaneous labor, preterm prelabor rupture of membranes (preterm PROM) and in the presence of microbial invasion of the amniotic cavity (MIAC). METHODS: In this cross-sectional study, visfatin concentration in AF was determined in patients in the following groups: 1) mid-trimester (n=75); 2) term not in labor (n=27); 3) term in spontaneous labor (n=51); 4) patients with preterm labor with intact membranes (PTL) without MIAC who delivered at term (n=35); 5) patients with PTL without MIAC who delivered preterm (n=52); 6) patients with PTL with MIAC (n=25); 7) women with preterm PROM without MIAC (n=26); and 8) women with preterm PROM with MIAC (n=26). Non-parametric statistics were used for analysis. RESULTS: 1) The median AF concentration of visfatin was significantly higher in patients at term than in mid-trimester; 2) Among women with PTL who delivered preterm, the median visfatin concentration was significantly higher in patients with MIAC than those without MIAC; 3) Similarly, patients with PTL and MIAC had a higher median AF visfatin concentration than those with PTL who delivered at term; 4) Among women with preterm PROM, the median AF visfatin concentration was significantly higher in patients with MIAC than those without MIAC. CONCLUSIONS: 1) Visfatin is a physiologic constituent of AF; 2) The concentration of AF visfatin increases with advancing gestational age; 3) AF visfatin concentration is elevated in patients with MIAC, regardless of the membrane status, suggesting that visfatin participates in the host response against infection.

Severe preeclampsia is characterized by increased placental expression of galectin-1.

OBJECTIVE: Galectin-1 is a major anti-inflammatory protein expressed by the placenta and immune cells that can bias the character of inflammatory responses toward the Th2 type. Galectin-1 is expressed in immune privileged sites, it can facilitate immune tolerance and tumor immune escape, and it has been successfully used for the suppression of experimental autoimmune diseases as well as graft-versus-host disease in murine models. We propose that an abnormal immune response in some pregnancy complications may be associated with changes in placental expression of galectin-1. To test this hypothesis, we studied placental galectin-1 mRNA and protein expression and localization in women with preeclampsia (PE) and in those who delivered a small-for-gestational age (SGA) neonate. STUDY DESIGN: This cross-sectional study included pregnant women matched for gestational age at delivery in the following groups: (1) severe PE (n = 10), (2) severe PE complicated with SGA (n = 10), (3) SGA without PE (n = 10), and (4) controls (n = 10). Galectin-1 mRNA and protein were localized in placentas by in situ hybridization and immunofluorescence microscopy. Galectin-1 mRNA expression was determined by quantitative real-time reverse transcription-polymerase chain reaction (RT-PCR), and galectin-1 protein content by Western blot. Non-parametric statistics were used for analysis. RESULT: (1) In normal term placentas, galectin-1 mRNA or immunofluorescence signals were detected in the trophoblasts, villous stromal cells, Hofbauer cells, endothelial cells of the villous blood vessels, and the villous stroma. (2) Placental galectin-1 mRNA expression was significantly higher in severe PE (with or without SGA) than in controls (1.47-fold, p = 0.004; 1.44-fold, p = 0.003, respectively) and in SGA (1.68-fold, p = 0.001; 1.64-fold, p = 0.001, respectively). (3) Trophoblasts in placentas of patients with severe PE had the most intense galectin-1 immunostaining. CONCLUSIONS: (1) We report for the first time the placental expression and localization of galectin-1 mRNA and demonstrate that the protein is abundantly present in third trimester human placentas. (2) Placental galectin-1 expression is higher in severe PE than in normal pregnancy regardless of the presence of SGA. (3) However, it is not altered in SGA without PE. We propose that the increased placental expression of galectin-1 in patients with severe PE may represent a fetal response to an exaggerated systemic maternal inflammation; thus, galectin-1 may be implicated in maternal-fetal immune tolerance in humans.

Angiogenesis gene expression in mouse uterus during the common pathway of parturition.

OBJECTIVE: The objective of the study was to investigate changes in the expression of angiogenesis-related genes during the common terminal pathway of parturition including spontaneous labor at term, as well as preterm labor (PTL), induced by either bacteria or ovariectomy. STUDY DESIGN: Preterm pregnant mice (14.5 days of gestation) were treated with the following: (1) intrauterine injection of media; (2) intrauterine injection of heat-inactivated Escherichia coli; (3) ovariectomy; and (4) sham operation. Tissues from mice at term (19.5 days of gestation) were collected at term not in labor, term in labor, and 12 hours postpartum. Angiogenesis-related gene expression levels were quantitated by the measurement of specific mRNAs in uterine tissue by RT-qPCR and analyzed by repeated-measures analysis of variance. RESULTS: The following results were found: (1) microarray analysis of the uterine transcriptome indicated an enrichment for the gene ontology category of angiogenesis in bacteria-induced PTL samples (P < or = .093); (2) several genes related to angiogenesis demonstrated significantly increased expression in samples in either term spontaneous labor or preterm labor; and (3) qRT-PCR measurements demonstrated that spontaneous term labor and preterm labor induced by either bacteria or ovariectomy all substantially increased the expression of multiple angiogenesis-related genes (P < or = .0003; Angpt2, Ctgf, Cyr61, Dscr1, Pgf, Serpine1, Thbs1, and Wisp 1). CONCLUSION: Spontaneous labor at term, as well as pathologically induced preterm labor, all result in greatly increased expression of angiogenesis-related genes in the uterus.

Placental growth hormone is increased in the maternal and fetal serum of patients with preeclampsia.

OBJECTIVES: Placental growth hormone (PGH) is a pregnancy-specific protein produced by syncytiotrophoblast and extravillous cytotrophoblast. No other cells have been reported to synthesize PGH Maternal. PGH Serum concentration increases with advancing gestational age, while quickly decreasing after delivery of the placenta. The biological properties of PGH include somatogenic, lactogenic, and lipolytic functions. The purpose of this study was to determine whether the maternal serum concentrations of PGH change in women with preeclampsia (PE), women with PE who deliver a small for gestational age neonate (PE + SGA), and those with SGA alone. STUDY DESIGN: This cross-sectional study included maternal serum from normal pregnant women (n = 61), patients with severe PE (n = 48), PE + SGA (n = 30), and SGA alone (n = 41). Fetal cord blood from uncomplicated pregnancies (n = 16) and PE (n = 16) was also analyzed. PGH concentrations were measured by ELISA. Non-parametric statistics were used for analysis. RESULTS: (1) Women with severe PE had a median serum concentration of PGH higher than normal pregnant women (PE: median 23,076 pg/mL (3473-94 256) vs. normal pregnancy: median 12 157 pg/mL (2617-34 016); p < 0.05), pregnant women who delivered an SGA neonate (SGA: median 10 206 pg/mL (1816-34 705); p < 0.05), as well as pregnant patients with PE and SGA (PE + SGA: median 11 027 pg/mL (1232-61 702); p < 0.05). (2) No significant differences were observed in the median maternal serum concentration of PGH among pregnant women with PE and SGA, SGA alone, and normal pregnancy (p > 0.05). (3) Compared to those of the control group, the median umbilical serum concentration of PGH was significantly higher in newborns of preeclamptic women (PE: median 356.1 pg/mL (72.6-20 946), normal pregnancy: median 128.5 pg/mL (21.6-255.9); p < 0.01). (4) PGH was detected in all samples of cord blood. CONCLUSIONS: (1) PE is associated with higher median concentrations of PGH in both the maternal and fetal circulation compared to normal pregnancy. (2) Patients with PE + SGA had lower maternal serum concentrations of PGH than preeclamptic patients without SGA. (3) Contrary to previous findings, PGH was detectable in the fetal circulation. The observations reported herein are novel and suggest that PGH may play a role in the mechanisms of disease in preeclampsia and fetal growth restriction.

Human trophoblast survival at low oxygen concentrations requires metalloproteinase-mediated shedding of heparin-binding EGF-like growth factor.

Heparin-binding EGF-like growth factor (HBEGF), which is expressed in the placenta during normal pregnancy, is down regulated in pre-eclampsia, a human pregnancy disorder associated with poor trophoblast differentiation and survival. This growth factor protects against apoptosis during stress, suggesting a role in trophoblast survival in the relatively low O(2) ( approximately 2%) environment of the first trimester conceptus. Using a well-characterized human first trimester cytotrophoblast cell line, we found that a 4-hour exposure to 2% O(2) upregulates HBEGF synthesis and secretion independently of an increase in its mRNA. Five other expressed members of the EGF family are largely unaffected. At 2% O(2), signaling via HER1 or HER4, known HBEGF receptors, is required for both HBEGF upregulation and protection against apoptosis. This positive-feedback loop is dependent on metalloproteinase-mediated cleavage and shedding of the HBEGF ectodomain. The restoration of trophoblast survival by the addition of soluble HBEGF in cultures exposed to low O(2) and metalloproteinase inhibitor suggests that the effects of HBEGF are mediated by autocrine/paracrine, rather than juxtacrine, signaling. Our results provide evidence that a post-transcriptional mechanism induced in trophoblasts by low O(2) rapidly amplifies HBEGF signaling to inhibit apoptosis. These findings have a high clinical significance, as the downregulation of HBEGF in pre-eclampsia is likely to be a contributing factor leading to the demise of trophoblasts.

Unexplained intrauterine fetal death is accompanied by activation of complement.

OBJECTIVE: Activation of the complement system has recently been implicated in the mechanisms of fetal loss in the antiphospholipid syndrome. It is, however, possible that complement activation is also involved in other causes of fetal death in the second and third trimesters of pregnancy. We therefore conducted a study to determine whether fetal death is associated with changes in the maternal plasma concentrations of complement split products or anaphylatoxins (C3a, C4a and C5a). STUDY DESIGN: A cross-sectional study was designed to include normal pregnant women (n=60) and patients with fetal death (n=60). Patients with fetal death were classified according to the cause of fetal demise into: a) unexplained (n=44); b) associated with preeclampsia (n=8); and c) associated with chromosomal abnormalities or major congenital fetal anomalies (n=8). The plasma concentrations of C3a, C4a and C5a were measured using sensitive and specific ELISAs. Non-parametric statistics were used for analysis. A P value of <0.05 was considered significant. RESULTS: 1) The median plasma concentration of C5a was higher in patients with fetal death than in normal pregnant women [median 16 ng/mL (range 4.5-402.5) vs. median 11.6 ng/mL (range 1.2-87.1), respectively; P<0.001]; 2) patients with an unexplained fetal death and those associated with preeclampsia had a higher median plasma C5a concentration than normal pregnant women (P=0.002 and P<0.001, respectively); 3) no differences were observed in the maternal plasma concentrations of C3a and C4a among the study groups. CONCLUSIONS: Unexplained fetal death is associated with evidence of complement activation.