Neutrophil Extracellular Trap Formation in Newborn Infants at Risk for Inflammatory Syndromes

Utah System of Higher Education (USHE)

Status: Suspended

Conditions: Prematurity; Necrotizing Enterocolitis

Study type: Observational

Funder types: Other; NIH

Identifiers

NCT01106209

119244

R01HD093826 (U.S. NIH Grant/Contract)

Details and patient eligibility

About

The purpose of this study is to characterize the time to maturation of neutrophil extracellular trap(NET) formation capability in polymorphonuclear leukocytes(PMNs) isolated from newborn premature and term infants as well as infants <1 year of age undergoing elective surgery. This study will also determine whether NETs contribute to the pathogenesis of necrotizing enterocolitis (NEC). We hypothesize that NET formation contributes to the pathogenesis of NEC by inappropriately releasing degradative proteins and tissue destructive enzymes into the inflammatory milieu of the premature infant gastrointestinal tract following bacterial translocation. We also hypothesize that the delay in NEC development in premature infants (3rd - 4th week of life) as compared to at-risk term infants (1st week of life) results from a developmental delay in PMN ability to form NETs.

Full description

Prematurely born infants are at risk for necrotizing enterocolitis (NEC), the most common gastrointestinal emergency encountered in the newborn intensive care unit. This disease occurs in between 5 - 10% of infants born at less than 30 weeks gestation or less than 1500 grams birth weight. In these patients, NEC routinely develops during the 3rd or 4th week of life. NEC rarely occurs in infants born closer to term; for these patients NEC usually develops during the 1st week of life. So far, no one has explained the inverse relationship between gestational age at birth and the delay in NEC development.

Recently, our laboratory described for the first time an inherent deficiency of innate immunity in newborn infants - failure of neutrophil extracellular trap formation. Neutrophil extracellular traps or NETs are complex lattices of extracellular chromatin and DNA decorated with anti-microbial proteins and degradative enzymes which trap and kill microbes. When the neutrophils of newborn infants develop the ability to form NETs and whether the maturation of NET formation correlates with development of NEC in at risk infants remains unknown.

We have therefore undertaken the following study best described as a prospective, in vitro longitudinal cellular biology study of LPS/PAF-stimulated PMNs isolated from the cord and peripheral blood of premature infants at risk for NEC and from term infants not considered at risk for NEC. We will also assay for NET formation in gastrointestinal tissue samples obtained at the time of surgery for severe NEC in enrolled prematurely born infants. These studies are the first of their kind and aim to answer these important questions.

Enrollment: 60 estimated patients

Sex: All

Ages: Under 1 year old

Volunteers: Accepts Healthy Volunteers

Inclusion criteria

1. Preterm infant patients delivered at UUMC and hospitalized in the NICU who are ≤ 1500 grams or <30 weeks gestational age at birth
2. Term infants delivered at UUMC without complication, either via cesarean section or vaginal delivery
3. Infants admitted to the PCMC same-day surgery unit in preparation for elective surgery within the first year of life.

Exclusion criteria

• No other exclusion criteria

Trial design

60 participants in 3 patient groups

Prematurely born infants in the NICU

Description:

Preterm infant patients delivered at UUMC and hospitalized in the NICU who are ≤1500 grams or \<30 weeks gestational age at birth

Healthy term infants

Description:

Term infants delivered at UUMC without complication, either via cesarean section or vaginal delivery

Infants having surgery at <1 year old

Description:

Infants admitted to the PCMC same-day surgery unit in preparation for elective surgery within the first year of life