Necrotizing enterocolitis (NEC) in preterm infantsjs.a complex, multi-factorial disease typically characterized by an exaggerated inflammatory response to pathogenic flora leading to bowel necrosis and often death. Dysregulated intestinal immune development may play an important role in the disease process, though this area is still poorly defined. To advance our understanding of NEC pathophysiology we propose to isolate adaptive immune cells from the lamina propria of surgically resected tissue from NEC patients and controls. We will test the hypothesis that a relative absence or reduced function of lamina propria F0XP3^ T regulatory cells (Treg) in the ileum of predisposed preterm infants is a risk factor for NEC. Treg are professional immune suppressor cells that are typically characterized as interleukin-2 receptor a (IL-2Ra = CD25)''"3'''CD4^ CD45RO* IL-7R (CD127)*"'T cells expressing high levels of the transcription factor forkhead box protein 3 (FOXPS). Depletion of Treg from the normal CD4* T cell pool or mutation ofthe FOXPS gene results in immune dysregulation involving the intestinal tract.
The Specific Aims ofthis proposal are to test the following three hypotheses: (1) Intestinal T effector cells (Teff) from preterm infants with NEC are less susceptible to Treg function. Intestinal Teff from preterm infants with NEC and controls will be compared for responsiveness to Treg by measuring inhibition of T cell proliferation. IL-2, IL-6, IL-17, TNF, and TGF-p levels in supernatants of Teff cultures will determine if NEC patients provide factors that promote or inhibit Treg generation, (2) Treg function in the ileum of preterm infants with NEC is limited. We will measure if Treg presence and/or function is reduced in NEC patients by comparing T cell suppression, cytokine production and FOXPS mRNA levels between NEC patients and controls and (3) Cord blood from preterm infants with NEC contains lower percentages of gut-homing Treg compared to controls. We will collect cord blood from infants less than 35 weeks gestational age and compare Treg presence and function between NEC patients and controls. Our findings will provide a more robust understanding of the immunological mechanisms that regulate the intestinal development of premature infants. This proposal develops novel translational approaches to identify cellular and molecular targets for reducing the pathologic host immune response in NEC and to detect infants at highest risk of this devastating disease.

Public Health Relevance

Necrotizing enterocolitis (NEC) is a common disease of the intestinal tract of premature infants that requires removal of affected intestinal tissue in one out of three cases and has a mortality rate of up to 50%. The proposed studies will test the role of specific cells (so called Treg) located in intestinal tissue in regulating the damaging immune responses associated with NEC. These studies will help identify patients at highest risk and provide the basis for the development of treatments to prevent or ameliorate this, often fatal, disease.

National Institute of Health (NIH)
Eunice Kennedy Shriver National Institute of Child Health & Human Development (NICHD)
Clinical Investigator Award (CIA) (K08)
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Study Section
Pediatrics Subcommittee (CHHD)
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Raju, Tonse N
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Vanderbilt University Medical Center
Schools of Medicine
United States
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Romano-Keeler, Joann; Weitkamp, Jörn-Hendrik (2015) Maternal influences on fetal microbial colonization and immune development. Pediatr Res 77:189-95
Weitkamp, Jörn-Hendrik; Rosen, Michael J; Zhao, Zhiguo et al. (2014) Small intestinal intraepithelial TCR??+ T lymphocytes are present in the premature intestine but selectively reduced in surgical necrotizing enterocolitis. PLoS One 9:e99042
Romano-Keeler, Joann; Moore, Daniel J; Wang, Chunlin et al. (2014) Early life establishment of site-specific microbial communities in the gut. Gut Microbes 5:192-201
Van Kaer, Luc; Algood, Holly M Scott; Singh, Kshipra et al. (2014) CD8??? innate-type lymphocytes in the intestinal epithelium mediate mucosal immunity. Immunity 41:451-64
Weitkamp, Jörn-Hendrik (2014) More than a gut feeling: predicting surgical necrotising enterocolitis. Gut 63:1205-6
Rosen, Michael J; Chaturvedi, Rupesh; Washington, M Kay et al. (2013) STAT6 deficiency ameliorates severity of oxazolone colitis by decreasing expression of claudin-2 and Th2-inducing cytokines. J Immunol 190:1849-58
Weitkamp, Jorn-Hendrik; Koyama, Tatsuki; Rock, Michael T et al. (2013) Necrotising enterocolitis is characterised by disrupted immune regulation and diminished mucosal regulatory (FOXP3)/effector (CD4, CD8) T cell ratios. Gut 62:73-82
Romano-Keeler, Joann; Weitkamp, Joern-Hendrik; Moore, Daniel J (2012) Regulatory properties of the intestinal microbiome effecting the development and treatment of diabetes. Curr Opin Endocrinol Diabetes Obes 19:73-80
Ullrich, Tim; Tang, Yi-Wei; Correa, Hernan et al. (2012) Absence of gastrointestinal pathogens in ileum tissue resected for necrotizing enterocolitis. Pediatr Infect Dis J 31:413-4
Engelhardt, Brian G; Jagasia, Shubhada M; Crowe Jr, James E et al. (2012) Predicting posttransplantation diabetes mellitus by regulatory T-cell phenotype: implications for metabolic intervention to modulate alloreactivity. Blood 119:2417-21

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