Serum chemokine levels and developmental outcome in preterm infants

Sex differences in the association of pretransfusion haemoglobin and cognition in preterm infants

OBJECTIVES

To assess sex-specific differences in the association between pre-transfusion haemoglobin values and early neurodevelopmental function.

DESIGN

Observational follow-up of infants with birth weights <1000 g and gestational ages 22-28 weeks who were enrolled in the NICHD Neonatal Research Network Transfusion of Prematures (TOP) Trial at 19 U.S. sites, 2012-2017.

MAIN OUTCOME MEASURES

Pretransfusion haemoglobin values were obtained longitudinally through 36 weeks' postmenstrual age. The infant's mean pretransfusion haemoglobin was used as a marker of degree of anaemia (n=1655 measures). Measures of brain function were obtained at 22-26 months' corrected age using the Bayley Scales of Infant & Toddler Development, third edition (BSID-III) (n=1290 BSID-III scores). Sex-specific estimates for the linear relation between pretransfusion haemoglobin and BSID-III scores were obtained from repeated-measures regression analysis, adjusted for gestational age, birth weight, study site, clinical characteristics, and demographic covariates.

RESULTS

The relation of pretransfusion haemoglobin with 24-month BSID-III scores showed significant, independent interactions with both (1) sex (p=0.046) and (2) retinopathy of prematurity (ROP; p=0.004). In 614 males, BSID-III scores were higher by 1.07 points per g/dL (95% CI 1.58 to 4.33; p=0.008), not differing significantly among the three subscales (cognitive, language and motor; p=0.94). In 247 infants with ROP, BSID-III scores were higher by 2.95 points per g/dL (95% CI 0.28 to 1.87; p<0.0001), uniformly across subscales (p=0.73). These associations were non-significant in 676 females (p=0.96) and 1043 infants without ROP (p=0.81).

CONCLUSIONS

This study demonstrates sex-specific associations between mean pretransfusion haemoglobin (a marker of the severity of anaemia throughout the neonatal intensive care unit [NICU] hospitalisation) and early neurodevelopmental function at 22-26 months' corrected age.

Associations between the human immune system and gut microbiome with neurodevelopment in the first 5 years of life: A systematic scoping review

The aim of this review was to map the literature assessing associations between maternal or infant immune or gut microbiome biomarkers and child neurodevelopmental outcomes within the first 5 years of life. We conducted a PRISMA-ScR compliant review of peer-reviewed, English-language journal articles. Studies reporting gut microbiome or immune system biomarkers and child neurodevelopmental outcomes prior to 5 years were eligible. Sixty-nine of 23,495 retrieved studies were included. Of these, 18 reported on the maternal immune system, 40 on the infant immune system, and 13 on the infant gut microbiome. No studies examined the maternal microbiome, and only one study examined biomarkers from both the immune system and the gut microbiome. Additionally, only one study included both maternal and infant biomarkers. Neurodevelopmental outcomes were assessed from 6 days to 5 years. Associations between biomarkers and neurodevelopmental outcomes were largely nonsignificant and small in effect size. While the immune system and gut microbiome are thought to have interactive impacts on the developing brain, there remains a paucity of published studies that report biomarkers from both systems and associations with child development outcomes. Heterogeneity of research designs and methodologies may also contribute to inconsistent findings. Future studies should integrate data across biological systems to generate novel insights into the biological underpinnings of early development.

Chorioamnionitis-exposure alters serum cytokine trends in premature neonates

OBJECTIVES

Determine if chronologic age and/or chorioamnionitis exposure alter normal serum cytokine and chemokine levels in uninfected preterm neonates during their initial NICU stay.

STUDY DESIGN

A 7-plex immunoassay measured levels of serum IL-1β, IL-6, IL-8, IL-10, TNF-α, CCL2, and CCL3 longitudinally from chorioamnionitis-exposed and unexposed preterm neonates under 33 weeks' gestation.

RESULTS

Chorioamnionitis-exposed and unexposed preterm neonates demonstrated differences in the trends of IL-1β, IL-6, IL-8, IL-10, TNF-α, and CCL2 over the first month of life. The unexposed neonates demonstrated elevated levels of these inflammatory markers in the first two weeks of life with a decrease by the third week of life, while the chorioamnionitis-exposed neonates demonstrated differences over time without a predictable pattern. Chorioamnionitis-exposed and unexposed neonates demonstrated altered IL-10 and TNF-α trajectories over the first twelve weeks of life.

CONCLUSION

Chorioamnionitis induces a state of immune dysregulation in preterm neonates that persists beyond the immediate neonatal period.

Thrombus calcification after removing peripherally inserted central catheters in extremely preterm infants

Pericatheter thrombus calcification is a complication that arises due to central venous catheter insertion and is particularly rare in peripherally inserted central catheters (PICCs). In this case report, we reviewed the clinical course of two neonates experiencing thrombus calcification. The first case involved a male neonate weighing 445 g. His PICC dwelt in the superior vena cava for over 49 days. Although a radiograph after removal did not show any silhouette, subsequent radiographs and CT depicted a catheter-like outline. Percutaneous intravascular retrieval was performed to salvage the object. Pathological examination revealed it to be a calcified cast. The calcified thrombosis was successfully dissolved with 6 months of warfarin therapy. The second case involved a male neonate weighing 534 g. After PICC removal, a catheter-like structure was shown on ultrasonograms. It was determined that invasive procedures were unnecessary for diagnosing the calcified thrombosis based on experience with the first case.

Sex Differences in the Association of Pretransfusion Hemoglobin Levels with Brain Structure and Function in the Preterm Infant

OBJECTIVE

To assess sex-specific differences in early brain structure and function of preterm infants after red blood cell (RBC) transfusions.

STUDY DESIGN

A single-center subset of infants with a birth weight <1000 g and gestational age 22-29 weeks were enrolled from the National Institute of Child Health and Human Development's Neonatal Research Network Transfusion of Prematures Trial. Hemoglobin (Hb) concentration obtained directly before each transfusion (pretransfusion Hb [ptHb]) was obtained longitudinally throughout each infant's neonatal intensive care unit stay and used as a marker of degree of anemia (n = 97). Measures of regional brain volumes using magnetic resonance imaging were obtained at ∼40 weeks postmenstrual age or at hospital discharge, if earlier (n = 29). Measures of brain function were obtained at 12 months corrected age using the Bayley Scales of Infant & Toddler Development, 3rd Edition (n = 34).

RESULTS

PtHb was positively correlated with neonatal cerebral white matter volume in males (B = +0.283; P = .006), but not females (B = -0.099; P = .713), resulting in a significant sex interaction (P = .010). Bayley-III gross motor scores and a pooled mean score were significantly lower in association with higher ptHb in females (gross motor score: B = -3.758; P = .013; pooled mean score: B = -1.225; P = .030), but not males (gross motor score: B = +1.758; P = .167; pooled mean score: B = +0.621; P = .359). Higher ptHb was associated with descriptively lower performance on multiple Bayley-III subscales in females, but not in males.

CONCLUSIONS

This study demonstrates sex-specific associations between an early marker of anemia and RBC transfusion status (ie, ptHb) with both neonatal white matter volume and early cognitive function at age 12 months in preterm infants.

Sex-specific cytokine responses and neurocognitive outcome after blood transfusions in preterm infants

BACKGROUND

The objective of this study was to determine sex-specific differences in inflammatory cytokine responses to red blood cell (RBC) transfusion in preterm infants in the neonatal period and their relationship to later neurocognitive status.

METHODS

Infants with a birth weight <1000 g and gestational age 22-29 weeks were enrolled in the Transfusion of Prematures (TOP) trial. The total number of transfusions was used as a marker of transfusion status. Nineteen cytokines and biomarkers were analyzed from 71 infants longitudinally during the neonatal period. Twenty-six infants completed the Bayley Scales of Infant & Toddler Development, 3rd Edition (Bayley-III) at 12 months' corrected age.

RESULTS

Nine cytokine levels were significantly elevated in proportion to the number of transfusions received. Of those, one cytokine showed a sex-specific finding (p = 0.004): monocyte chemoattractant protein-1, MCP-1, rose substantially in females (8.9% change per additional transfusion), but not in males (-0.8% change). Higher concentrations of MCP-1 exclusively were associated with worse Bayley-III scores: decreased cognitive raw scores (p = 0.0005) and motor scaled scores (p < 0.0001).

CONCLUSIONS

This study provides evidence of a sex-specific difference in the inflammatory response to RBC transfusions during neonatal life, with MCP-1 levels rising only in females and inversely correlating with neurocognitive status at 12 months old.

IMPACT

It is important to understand the risk factors for abnormal neurodevelopment in preterm infants, including anemia and RBC transfusion, in order to improve outcomes and provide potential targets for therapy. Our study investigates and provides the first evidence of sex-specific differences in inflammatory cytokine responses to RBC transfusions in preterm infants in the neonatal period, and their relationship to later cognitive outcomes. This study critically suggests that different transfusion thresholds may have a sex-specific effect on neurodevelopment: females have worse cognitive outcomes with increased number of transfusions, while males have worse outcomes with lower number of transfusions.

Interleukin-8 dysregulation is implicated in brain dysmaturation following preterm birth

BACKGROUND

Preterm birth is associated with dysconnectivity of structural brain networks, impaired cognition and psychiatric disease. Systemic inflammation contributes to cerebral dysconnectivity, but the immune mediators driving this association are poorly understood. We analysed information from placenta, umbilical cord and neonatal blood, and brain MRI to determine which immune mediators link perinatal systemic inflammation with dysconnectivity of structural brain networks.

METHODS

Participants were 102 preterm infants (mean gestational age 29⁺¹ weeks, range 23⁺³-32⁺⁰). Placental histopathology identified reaction patterns indicative of histologic chorioamnionitis (HCA), and a customized immunoassay of 24 inflammation-associated proteins selected to reflect the neonatal innate and adaptive immune response was performed from umbilical cord (n = 55) and postnatal day 5 blood samples (n = 71). Brain MRI scans were acquired at term-equivalent age (41⁺⁰ weeks [range 38⁺⁰-44⁺⁴ weeks]) and alterations in white matter connectivity were inferred from mean diffusivity and neurite density index across the white matter skeleton.

RESULTS

HCA was associated with elevated concentrations of C5a, C9, CRP, IL-1β, IL-6, IL-8 and MCP-1 in cord blood, and IL-8 concentration predicted HCA with an area under the receiver operator curve of 0.917 (95% CI 0.841 - 0.993, p < 0.001). Fourteen analytes explained 66% of the variance in the postnatal profile (BDNF, C3, C5a, C9, CRP, IL-1β, IL-6, IL-8, IL-18, MCP-1, MIP-1β, MMP-9, RANTES and TNF-α). Of these, IL-8 was associated with altered neurite density index across the white matter skeleton after adjustment for gestational age at birth and at scan (β = 0.221, p = 0.037).

CONCLUSIONS

These findings suggest that IL-8 dysregulation has a role in linking perinatal systemic inflammation and atypical white matter development in preterm infants.

Inflammatory predictors of neurobehavior in very preterm infants

BACKGROUND

Preterm infants are at risk for impaired neurodevelopment. Inflammation may be an important modifiable mediator of preterm birth and neurodevelopmental impairment, but few studies have examined longitudinal measures of inflammation.

OBJECTIVE

To determine the relationship between longitudinal measures of inflammation and neurobehavior in very preterm infants.

STUDY DESIGN

Non-experimental, repeated measures cohort study.

METHODS

Very preterm infants were enrolled between October 2017 and December 2018. Blood was collected weekly until 35 weeks post-menstrual age for the quantification of plasma cytokines. Neurobehavior was assessed at 35 weeks post-menstrual age using the cluster scores for motor development and vigor and alertness/orientation from the Neurobehavioral Assessment of the Preterm Infant. Multiple linear regression models with robust standard errors were used to analyze the data. Average levels of individual cytokines, cytokine trends, and composite scores were used as measures of inflammation.

RESULTS

Seventy-three infants were enrolled in the study. Interleukin-1 receptor antagonist was associated with motor development and vigor scores. Interleukin-6 was associated with alertness/orientation scores. Tumor necrosis factor-alpha and composite scores of inflammation were associated with motor development and vigor and alertness/orientation scores. There were interactions with post-menstrual age at birth and infant sex.

CONCLUSION

Inflammation may be an important predictor of short-term neurobehavior in preterm infants. Interleukin-1 receptor antagonist, interleukin-6, and tumor necrosis factor-alpha are key cytokines for studies of preterm infants, but composite scores may be a better measure of inflammation than individual cytokines. Inflammation can be damaging to the immature brain and may be a specific target for future interventions to improve outcomes.

The Role of Brain-Derived Neurotrophic Factor and Glial Cell Line-Derived Neurotrophic Factor in Chronic Fetal Oxygen Deprivation

The aim of the study was to define the role of brain-derived and glial cell line-derived neurotrophic factors (BDNF and GDNF) in realization of compensative and adaptive mechanisms of a neonatal organism to hypoxia.

Inflammatory biomarkers in children with cerebral palsy: A systematic review

BACKGROUND

An exacerbated systemic inflammatory response has been associated with the occurrence of central nervous system injuries that may determine, in long term, motor, sensorial and cognitive disabilities. Persistence of this exacerbated inflammatory response seems to be involved in the pathophysiology of cerebral palsy (CP).

METHODS

A systematic search was conducted in Bireme, Embase, PubMed and Scopus including studies that were published until August 2019. The key words used were "cerebral palsy", "brain injury", "inflammation", "oxidative stress", "cytokines", "chemokines", "neuropsychomotor development", "neurodevelopment outcomes" and "child". The quality of the eligible studies was determined according to the criteria suggested by the Newcastle-Ottawa Scale (NOS).

RESULTS

Fourteen eligible studies aimed to investigate the association between peripheral inflammatory molecules and neurodevelopment in infants. The studies differed regarding CP-related risk factors and its classification. Inflammatory proteins were measured in blood, plasma, serum, cerebrospinal fluid or urine. In ten studies, higher circulating levels of cytokines, including IL-1β, IL-6, TNF and CXCL8/IL-8, were associated with abnormal neurological findings.

CONCLUSION

The investigation of the potential association between inflammatory molecules and neurological development in children with CP requires further original studies in order to clarify the influence of prenatal and perinatal inflammation on neurological outcomes.

Inflammatory mediators of stress exposure and neurodevelopment in very preterm infants: Protocol for the stress neuro-immune study

AIMS

(a) Determine relationships among stress exposure, inflammation, and neurodevelopment in very preterm infants and determine the mediated effect of inflammation on the relationship between stress exposure and neurodevelopment; (b) describe cytokine trajectories following birth and determine the effect of stress exposure on these trajectories; and (c) examine relationships between stress exposure and chronic stress responses in very preterm infants.

DESIGN

Non-experimental, repeated measures.

METHODS

Very preterm infants born 28-31 weeks post menstrual age will be enrolled. Cumulative stress exposure over the first 14 days of life will be measured using the Neonatal Infant Stressor Scale. Blood will be collected weekly for the quantification of cytokines. Neurodevelopment will be assessed using the Neurobehavioral Assessment of the Preterm Infant and hair for quantification of hair cortisol will be collected at 35 weeks post menstrual age. Multiple linear regression and conditional process analysis will be used to analyse the relationships among stress exposure, inflammation and neurodevelopment. Linear mixed models will be used to determine inflammatory trajectories over time. IRB approval for the study was received May 2017, and funding from the National Institute of Nursing Research was awarded July 2017.

DISCUSSION

This study will determine the extent to which inflammation mediates the relationship between stress exposure and neurodevelopment. Interventions to attenuate inflammation in preterm infants may improve outcomes.

IMPACT

Determining the potentially modifiable mediators of stress exposure and neurodevelopment in preterm infants is critical to improving long-term outcomes.

An Integrative Review of Cytokine/Chemokine Predictors of Neurodevelopment in Preterm Infants

Preterm infants are at risk of brain injury and poor neurodevelopmental outcomes including impairments in cognition, behavioral functioning, sensory perception, and motor performance. Systemic inflammation has been identified as an important, potentially modifiable precursor of neurologic and neurodevelopmental impairments. Inflammation is typically measured by quantifying circulating cytokines and chemokines. However, it is unclear which specific cytokines/chemokines most consistently predict neurodevelopment in preterm infants. In this integrative review, we evaluated and analyzed the literature (N = 37 publications) to determine the cytokines/chemokines most predictive of neurodevelopment in preterm infants, the optimal timing for these measurements, and the ideal source for collecting cytokines/chemokines. Synthesis of the findings of these studies revealed that interleukin (IL)-6, IL-1β, IL-8, and tumor necrosis factor (TNF)-α collected during the first 3 weeks of life are most predictive of subsequent neurodevelopment. Methodological variation among studies hinders more specific analysis, including the evaluation of cytokine thresholds and meta-analyses, that would allow for the use of cytokines/chemokines to predict neurodevelopment. Future research should focus on identifying explicit cytokine values, specifically for IL-6, IL-1β, IL-8, and TNF-α, that are most predictive for identifying preterm infants most at risk of impairment, keeping in mind that longitudinal measures of cytokines/chemokines may be more predictive of future outcomes than single-time point measures.

The biological embedding of neonatal stress exposure: A conceptual model describing the mechanisms of stress-induced neurodevelopmental impairment in preterm infants

The biological embedding of early life stress exposure may result in life-long neurodevelopmental impairment in preterm infants. Infants hospitalized in the neonatal intensive care unit are exposed to significant experiential, environmental, and physiologic stressors over the course of their extended hospitalization. Stress exposure during the sensitive period of brain development may alter biological processes, including functioning of the immune system, the autonomic nervous system, and the hypothalamic-pituitary-adrenal axis as well as gene expression. These alterations may subsequently affect brain structure and function. Changes to these processes may mediate the relationship between neonatal stress exposure and neurodevelopment in preterm infants and represent potential therapeutic targets to improve long-term outcomes. The purpose of this paper is to introduce a conceptual model, based on published research, that describes the mechanisms mediating stress exposure and neurodevelopment impairment in preterm infants and to provide the theoretical foundation on which to base future descriptive research, intervention studies, and clinical care.

Inflammatory molecules and neurotrophic factors as biomarkers of neuropsychomotor development in preterm neonates: A Systematic Review

OBJECTIVE

To provide a systematic review investigating the role of inflammatory molecules and neurotrophic factors as biomarkers of neuropsychomotor development in preterm neonates.

DATA SOURCE

Databases including PubMed, BIREME, and Scopus were systematically searched. Observational studies, as well as transversal, and cohort studies using human subjects published from 1990 to September 2017 were eligible for inclusion. Two authors independently identified eligible studies and analyzed their characteristics, quality, and accuracy in depth.

DATA SYNTHESIS

11 eligible studies clearly investigated the association between peripheral inflammation and motor and/or cognitive development in preterm infants. However, the selected populations differed in relation to the events associated with prematurity and the risk factors to abnormal motor and/or cognitive development. These studies measured circulating levels of cytokines, chemokines, adhesion molecules, acute phase proteins, and growth factors. The most commonly analyzed proteins were IL-1β, IL-6, TNF, CCL5/RANTES, CXCL8/IL-8, IGFBP-1, and VEGF. In seven of the eligible studies, plasma levels of IL-6 correlated with development delay. Two studies reported correlation between CXCL8/IL-8 plasma levels with cognitive and motor delay. In one study, higher levels of MCP-1/CCL2 were associated with better cognitive and motor outcome.

CONCLUSION

There is preliminary evidence indicating that circulating inflammatory molecules are associated with motor and cognitive development in preterm neonates, even considering different populations.

Urinary Levels of IL-1β and GDNF in Preterm Neonates as Potential Biomarkers of Motor Development: A Prospective Study

Objectives. To evaluate the association between inflammatory biomarkers, neurotrophic factors, birth conditions, and the presence of motor development abnormalities in preterm neonates. Methods. Plasma and urinary levels of cytokines (IL-1β, IL-6, IL-10, TNF, and IL-12p70), chemokines (CXCL8/IL-8, CCL2/MCP-1, CCL5/RANTES, CXCL10/IP-10, and CXCL9/MIG), and neurotrophic factors (BDNF and GDNF) were evaluated in 40 preterm neonates born between 28 and 32 incomplete weeks of gestation, at four distinct time points: at birth (umbilical cord blood) (T0), at 48 (T1), at 72 hours (T2), and at 3 weeks after birth (T3). Biomarkers levels were compared between different time points and then associated with Test of Infant Motor Performance (TIMP) percentiles. Results. Maternal age, plasma, and urinary concentrations of inflammatory molecules and neurotrophic factors were significantly different between groups with normal versus lower than expected motor development. Higher levels of GDNF were found in the group with lower than expected motor development, while IL-1β and CXCL8/IL-8 values were higher in the group with typical motor development. Conclusion. Measurements of cytokines and neurotrophic factors in spot urine may be useful in the follow-up of motor development in preterm neonates.

Circulating Inflammatory-Associated Proteins in the First Month of Life and Cognitive Impairment at Age 10 Years in Children Born Extremely Preterm

OBJECTIVES

To evaluate whether in children born extremely preterm, indicators of sustained systemic inflammation in the first month of life are associated with cognitive impairment at school age.

STUDY DESIGN

A total of 873 of 966 eligible children previously enrolled in the multicenter Extremely Low Gestational Age Newborn Study from 2002 to 2004 were evaluated at age 10 years. We analyzed the relationship between elevated blood concentrations of inflammation-associated proteins in the first 2 weeks ("early elevations"; n = 812) and the third and fourth week ("late elevations"; n = 532) of life with neurocognition.

RESULTS

Early elevations of C-reactive protein, tumor necrosis factor-α, interleukin (IL)-8, intercellular adhesion molecule (ICAM)-1, and erythropoietin were associated with IQ values >2 SD below the expected mean (ORs: 2.0-2.3) and with moderate to severe cognitive impairment on a composite measure of IQ and executive function (ORs: 2.1-3.6). Additionally, severe cognitive impairment was associated with late protein elevations of C-reactive protein (OR: 4.0; 95% CI 1.5, 10), IL-8 (OR: 5.0; 1.9, 13), ICAM-1 (OR: 6.5; 2.6, 16), vascular endothelial growth factor-receptor 2 (OR: 3.2; 1.2, 8.3), and thyroid-stimulating hormone (OR: 3.1; 1.3, 7.3). Moderate cognitive impairment was most strongly associated with elevations of IL-8, ICAM-1, and vascular endothelial growth factor-receptor 2. When 4 or more inflammatory proteins were elevated early, the risk of having an IQ <70 and having overall impaired cognitive ability was more than doubled (ORs: 2.1-2.4); the presence of 4 or more inflammatory protein elevated late was strongly linked to adverse cognitive outcomes (ORs: 2.9-4.8).

CONCLUSIONS

Extremely preterm children who had sustained elevations of inflammation-related proteins in the first postnatal month are more likely than extremely preterm peers without such elevations to have cognitive impairment at 10 years.

Extremely preterm infants small for gestational age are at risk for motor impairment at 3 years corrected age

BACKGROUND

Few studies have targeted psychomotor development and associated perinatal risk factors in Japanese very low birth weight (VLBW) infants who are severely small for gestational age (SGA).

DESIGN/SUBJECTS

A single-center study was conducted in 104 Japanese VLBW infants who were born preterm, due to maternal, umbilical cord, or placental abnormalities, between 2000 and 2007. Psychomotor development as a developmental quotient (DQ) was assessed using the Kyoto Scale of Psychological Development at 3 years corrected age. Severely SGA was defined as birth weight or length below -2 standard deviation values of the mean values at the same gestation. VLBW infants were divided into 2 subgroups based on gestational age at birth: ⩾28 weeks (n=64) and <28 weeks (n=40). DQs of infants with severe SGA were compared with those of infants who were appropriate for gestational age (AGA). Factors associated with developmental disabilities in VLBW infants with severe SGA (n=23) were determined.

RESULTS

In the group born at ⩾28 weeks gestation, infants with severe SGA had normal DQ values and did not significantly differ from those with AGA. However, in the group born at <28 weeks gestation, severe SGA infants had significantly lower postural-motor DQ values than AGA infants. Gestational age <28 weeks was an independent factor for low postural-motor DQ, regardless of the cause of severe SGA or pregnancy termination.

CONCLUSIONS

Extremely preterm newborns with severe SGA are at risk of motor developmental disability at age 3 years.

Plasma cytokines and markers of endothelial activation increase after packed red blood cell transfusion in the preterm infant

BACKGROUND

Transfusion of packed red blood cells (PRBCs) saves lives in the neonatal critical care setting and is one of the most common interventions in the preterm infant. The number and volume of PRBC transfusions are associated with several major neonatal morbidities, although a direct causal link between transfusion and major neonatal morbidity is still to be proven. Transfusion-related immunomodulation (TRIM) may underlie these adverse outcomes, yet it has received little attention in the high-risk preterm infant.

METHODS

One transfusion event was studied in infants ≤28 wk gestation between 2 and 6 wk postnatal age (n = 28). Plasma inflammatory cytokines and markers of endothelial activation were measured in the infants before and 2-4 h after transfusion, as well as in the donor pack.

RESULTS

Median (range) age at transfusion was 18 (14-39) days with the pretransfusion hemoglobin level at 9.8 (7.4-10.2) g/dl. Interleukin (IL)-1β (P = 0.01), IL-8 (P = <0.001), tumor necrosis factor-α (P = 0.008), and monocyte chemoattractant protein (P = 0.01) were increased after transfusion. A similar elevation in markers of endothelial activation was seen after transfusion with increased plasma macrophage inhibitory factor (P = 0.005) and soluble intracellular adhesion molecule-1 (P = <0.001).

CONCLUSION

Production of inflammatory cytokines and immunoactivation of the endothelium observed after the transfusion of PRBCs in the preterm infant may be a manifestation of TRIM. The implications of this emerging phenomenon within the preterm neonatal population warrant further investigation.

Elevated cytokine and chemokine levels in the placenta are associated with in-utero HIV-1 mother-to-child transmission

OBJECTIVE

To determine whether there is an association between cytokine and chemokine levels in plasma isolated from the placenta and HIV-1 mother-to-child transmission (MTCT).

DESIGN

We designed a case-control study of HIV-infected, pregnant women enrolled in the Malaria and HIV in Pregnancy cohort. Participants were recruited in Blantyre, Malawi, from 2000 to 2004. Patients were women whose children were HIV-1 DNA-positive at birth (in-utero MTCT) or HIV-1 DNA-negative at birth and HIV-1 DNA-positive at 6 weeks postpartum (intrapartum MTCT); controls were women whose children were HIV-1 DNA-negative both at birth and 6 weeks postpartum.

METHODS

After delivery, blood was isolated from an incision on the basal plate of the placenta. We used a Bio-Plex human cytokine assay (Bio-Rad, Hercules, California USA) to simultaneously quantify 27 cytokines, chemokines and growth factors in placental plasma. HIV-1 RNA copies were quantified with the Roche Amplicor kit.

RESULTS

Levels of interleukin (IL) 4, IL-5, IL-6, IL-7, IL-9, eotaxin, IL-1Ra and interferon gamma-induced protein 10 (IP-10) were significantly elevated in placental plasma isolated from cases of in-utero HIV-1 MTCT. In contrast, only granulocyte colony-stimulating factor was elevated in placental plasma isolated from cases of intrapartum MTCT. After adjusting for maternal age, gestational age and peripheral CD4(+) T-cell count, every log(10) increase in placental IP-10 was associated with a three-fold increase in the prevalence of in-utero HIV-1 MTCT.

CONCLUSION

Elevated cytokine and chemokine levels in placental plasma were associated with in-utero and not intrapartum MTCT. IP-10, which is both a T-cell chemokine and potentiator of HIV-replication, was robustly and independently associated with prevalent, in-utero MTCT.