J ALLERGY CLIN IMMUNOL

FEBRUARY 2013

AB102 Abstracts

SUNDAY

370 Association of Stress, Pruruitis and Illness Severity inChildren with Atopic Dermatitis

Kimberly Kelsay, MD1, Eleni Weisnicht2,3, Bruce G. Bender, PhD

FAAAAI4, Donald Y. M. Leung, MD, PhD, FAAAAI4, Mary D. Klinnert,

PhD4,5; 1University of Colorado, School of Medicine, Aurora, 2National

Jewish Health, 3Univeristy of Colorado, Boulder, 4National Jewish

Health, Denver, CO, 5University of Colorado School of Medicine.

RATIONALE: For children with atopic dermatitis (AD), itching is the

primary factor affecting quality of life. In adults with AD, psychological

stress increases inflammation (including total IgE) and pruritus. These

relationships have not been examined in children.We hypothesized that for

children with AD, psychological stress would be associated with increased

IgE levels and also with AD severity and/or pruritus.

METHODS: 69 childrenwithAD,mean age 4.9 (SD53.2) years old, 59%

male, 72% Caucasian, were enrolled upon admission to National Jewish

Health. Parents completed Child Behavior Checklist, and Affective

Disorders scale t-score was used as marker of child stress. Clinicians and

parents completed ratings of atopic dermatitis severity and pruritis using

the SCORAD and Atopic Dermatitis Quickscore (ADQ), respectively.

Total serum IgE levels at admission were obtained from chart review. Total

IgE was log transformed and Spearman’s correlations were computed.

RESULTS: Children’s psychological stress was correlated with clinician

rated pruritis (r50.38, p<0.05) and both parent rated pruritus (r50.28,

p<0.001) and severity of AD (r50.34, p<0.05). Stress was also correlated

with total IgE (r50.27, p<0.05). In addition, total IgE was correlated with

clinician rated severity (r50.22, p<0.001), and both parent rated pruritus

(r50.44, p<0.001) and severity (r50.47, p<0.001).CONCLUSIONS: As hypothesized, children with AD with greater

psychological stress had higher total IgE, increased pruritis and more

severe AD. Reduction of psychological stress may be a key intervention

strategy for children with AD. Investigation is needed to test effects of

behavioral interventions and their physiological mechanisms.

371 Human Basophils Express Novel TSLPR Variants Including aPutative Secreted Form

Martin J. Romeo, PhD1, Rachana Agrawal, PhD1, Anna Pom�es, PhD,

FAAAAI2, Judith A. Woodfolk, MBChB, PhD, FAAAAI1; 1University

of Virginia, Charlottesville, VA, 2Indoor Biotechnologies, Inc., Charlot-

tesville, VA.

RATIONALE: Basophils from atopic dermatitis (AD) patients efficiently

upregulate thymic stromal lymphopoietin receptor (TSLPR) surface

expression upon allergen stimulation, but fail to express interleukin-7

receptor alpha (IL-7Ra). We hypothesized that activated basophils express

non-canonical variants of TSLPR that arise from alternative RNA splicing

events.

METHODS: Sort purified basophils from 2 AD patients and a control

were cultured in complete medium containing autologous serum for 4 to

5 hours in the presence or absence of allergen. Total RNA from these cells

was reverse transcribed into first-strand cDNA and analyzed by quantita-

tive and qualitative PCR using transcript-specific primer pairs. Molecular

modeling of proteins encoded by canonical and non-canonical TSLPR

transcripts was performed using Swiss-Prot.

RESULTS: Two novel TSLPR transcripts were preferentially induced in

activated basophils from AD patients only. Predicted protein products of

these transcripts corresponded to a truncated variant lacking an N-terminal

extracellular fibronectin III domain, and to a putative secreted form with a

unique C-terminus lacking an obvious membrane spanning region.

Molecular modeling based on homology to related cytokine receptors

predicted overall structural similarity among the extracellular domains of

all 3 variants but variable ligand binding potential owing to either

alterations in amino acid side chain orientation or to the presence of unique

residues in the cytokine binding ‘‘elbow’’ regions of these molecules.

CONCLUSIONS: Activated basophils express novel TSLPR splice

variants, including a putative secreted form. We propose that production

of these variants may contribute to regulation of the TSLP pathway in

allergic disease.

372 Early Life Transepidermal Water Loss (TEWL) Values CanPredate Atopic Dermatitis At Six and Twelve Months inAsymptomatic Infants: Results From the Baseline Study

Maeve M. Kelleher1, Audrey Dunn Galvin1, Deirdre Murray1, Alan

David Irvine2, Jonathan O. Hourihane1, Baseline Team1; 1University

College Cork, Ireland, 2Trinity College Dublin, Dublin, Ireland.

RATIONALE: Atopic Dermatitis (AD) is a multifactorial disease. We

sought to ascertain whether a non invasive measurement of skin barrier

function at birth could predict the development of eczema in asymptomatic

infants enrolled in an unselected prospective birth cohort.

METHODS: 1903 infants were enrolled on the Cork BASELINE Birth

Cohort study from July 2009 to Oct 2011. Infants had TEWL measured at

birth, 2 and 6 months. AD was assessed at 6 and 12 months, using the UK

Diagnostic Criteria. Severity was assessed by SCORAD method at

6 months and by both SCORAD and Nottingham Severity Score (NSS)

at 12 months. Multiple regression analyses were conducted to investigate

the relationship between TEWL values and eczema at both time points.

Birthweight, parental allergy, sex, the use of emollient, and washing at

birth were included in the predictive models.

RESULTS: Eczema rate was 19% (292/1537) at 6 months and 16% (212/

1315). The multiple regression model controlling for sex, use of emollient,

washing, and eczema was statistically significant for eczema in asymp-

tomatic 2 month old infants at both 6 months [R2 50.02, F5 3.8, p<0.05]and 12 months [R2 50.04, F5 8.2, p<0.05]. Parental allergy did not con-

tribute to the model.

CONCLUSIONS: A signal for impaired skin barrier function is not seen

at birth. By 2 months TEWL can be used as a predictor for developing AD

in later infancy in asymptomatic infants. An intervention trial in these

infants to maintain skin barrier function would be welcome.

373 Leukotriene B4 Driven Neutrophil Recruitment to the Skin IsEssential for Allergic Skin Inflammation

Michiko K. Oyoshi, PhD1, Rui He1, Yitang Li1, Subhanjan Mondal1,

Juhan Yoon1, Roshi Afshar2, Mei Chen3, David M. Lee, MD, PhD3,

Hongbo Luo1, Andrew D. Luster, MD, PhD2, John Cho4, Lloyd Miller4,

Allison Larson3, George Murphy5, Raif Geha, MD1; 1Boston Children’s

Hospital, Boston, MA, 2Massachusetts General Hospital, Charlestown,

MA, 3Brigham and Women’s Hospital, 4University of California Los

Angeles, 5Brigham and Women’s Hospital/Harvard Medical School,

Boston, MA.

RATIONALE: Scratching triggers skin flares in atopic dermatitis (AD)

with Th2 cell infiltration in the skin lesions. Leukotriene B4 (LTB4) levels

are elevated in AD lesions. We examined the potential role of LTB4 in AD.

METHODS: Scratched skin samples were obtained from healthy adults.

The skin of BLT1-/- and LTA4H-/- mice andWT controls were tape stripped

or epicutaneously (EC) sensitized by application of ovalbumin (OVA) to

tape stripped skin. Skin histology was assessed by H&E staining and im-

munohistochemistry. LTB4 concentrations were determined using solid

phase extraction. Cytokine mRNA expression was examined by qPCR.

RESULTS: Scratching of healthy human skin, and its surrogate, tape

stripping of mouse skin, caused cutaneous neutrophil influx. This influx in

mice was largely dependent on the generation of LTB4 by neutrophils and

their expression of the LTB4 receptor BLT1. Allergic skin inflammation,

evidenced by increased epidermal and dermal thickness, dermal infiltration

by CD4+ T cells and eosinophils, and Th2 cytokine mRNA expression in

the skin in response to EC sensitization with OVAwas severely impaired

in BLT1-/- mice, and required the expression of BLT1 on both T cells

and non-T cells. Co-transfer of WT neutrophils, but not neutrophils defi-

cient in BLT1 or the LTB4 synthesizing enzymeLTA4H, restored the ability

of WT CD4+ effector T cells to transfer allergic skin inflammation to

BLT1-/- recipients. Pharmacologic blockade of LTB4 synthesis inhibited

allergic skin inflammation elicited by cutaneous antigen challenge in pre-

viously EC-sensitized mice.

CONCLUSIONS: The neutrophil-T cell axis reliant on LTB4-BLT1 inter-

action is required for allergic skin inflammation in mice.