J ALLERGY CLIN IMMUNOL Abstracts S279VOLUME 117, NUMBER 2

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1076 Protollin Adjuvanted Birch Pollen Extract Induces Long-Term Prevention of Airway Inflammation in a Mouse Modelof Allergic Asthma

C. R. Rioux1, N. Karp2, H. Koohsari1, A. Migneault1, D. S. Burt1, J. G.

Martin2, Q. A. Hamid2; 1ID Biomedical, Laval, PQ, CANADA, 2McGill

University, Montreal, PQ, CANADA.

RATIONALE: In birch pollen allergic mice, nasal immunization with

birch pollen extract mixed with the adjuvant Protollin (BPEx/Protollin)

induces a switch from type 2 to type 1 immunity that is maintained upon

subsequent BPEx challenge. In a mouse model of allergic asthma, nasal

immunization with BPEx/Protollin significantly prevented airway hyper-

responsiveness and airway inflammation following BPEx challenges done

a few days post-immunization. We now report on the longevity of this

protective effect on airway inflammation by BPEx/Protollin.

METHODS: BALB/c mice were sensitized intraperitoneally with BPEx

and alum and treated three times nasally on days 7, 10, and 13 with BPEx

or BPEx/Protollin. The mice were then challenged nasally three times on

three consecutive days with BPEx initiated either 2 days, 3 weeks, or 6

weeks post-final immunization. Airway inflammation was evaluated by

differential cell counts in bronchoalveolar lavages (BALs) and by quan-

tification of goblet cells in bronchioles.

RESULTS: In mice challenged with BPEx at either 2 days, 3 weeks, or 6

weeks post-immunization, nasal BPEx/Protollin decreased BAL

eosinophils by 40%, 60%, and 65% and BAL lymphocytes by 70%, 30%,

and 50%, respectively, compared with mice treated with BPEx alone.

Quantities of mucus-producing bronchial goblet cells were decreased by

65% and 48% in BPEx/Protollin treated mice challenged 2 days or 6

weeks respectively post-immunization compared with control mice.

CONCLUSIONS: The ability of Protollin-based allergen formulations to

induce long-lived prevention of airway inflammation in mice suggests

that they are strong candidate prophylactic treatments for the allergic asth-

ma in humans.

Funding: ID Biomedical

1077 Effects of Tacrolimus on Neutrophil Superoxide Productionin Asthmatics Compared to Controls

S. M. Bonilla, N. Bobba, E. Park, B. Goldberg; Allergy and Immunology,

Kaiser Permanente Los Angeles Medical Center, Los Angeles, CA.

RATIONALE: FK-506 (Tacrolimus) has been shown to inhibit superox-

ide O2- anion production in TNF-� primed neutrophils but not in

unprimed cells in vitro. Neutrophils from asthmatics are known to be

primed by cytokines such as TNF-� which enhance production of O2-

upon stimulation with receptor-based agents such as N-formyl-methionyl-

leucyl-phenylalanine (FMLP). We therefore reasoned that neutrophils

from asthmatics may be more susceptible to Tacrolimus inhibition than

those from normal controls.

METHODS: Neutrophils were obtained from 10 subjects with asthma

and 9 non-atopic controls. The neutrophils were incubated with 5 �g/ml

of cytochalasin B and 1 �M Tacrolimus then stimulated by 1 �M FMLP.

Superoxide production was determined by measuring cytochrome c

reduction at 550 nm in the presence and absence of superoxide dismutase.

RESULTS: Mean superoxide production (nM/107 cells) from asthmatic

subjects was 158.3 compared to 144.6 for controls. Addition of

Tacrolimus resulted in mean superoxide production of 134.8 for asthma

patients compared to 145.7 for controls.

CONCLUSIONS: Tacrolimus inhibited superoxide production from neu-

trophils of asthmatic subjects by approximately 15% but did not inhibit

superoxide production from control cells.

Funding: Kaiser Permanente Los Angeles Medical Center

1078 The Effect of BCG Treatment on the Allergic Responses in aMurine Model of Chronic Asthma

S. S. Kwon, C. H. Kim, J. H. Ahn, S. Y. Lee, S. J. Kim, Y. K. Kim, K. H.

Kim, H. S. Moon, J. S. Song, S. H. Park; Dept. of Internal Medicine,

Catholic University of Korea, Medical College, Seoul, REPUBLIC OF

KOREA.

RATIONALE: In order to investigate the effect of BCG on the allergic

responses in a murine model of chronic asthma, we observed the change

of airway remodelling, allergic inflammatory responses and airway hyper-

responsiveness in the established asthmatic mice after BCG via subcuta-

neous injection.

METHODS: Mice in BCG group received 2�104 colony-forming

units/100 �l of BCG subcutaneously on days 14, 21 and 28, whereas mice

in asthma group received phosphate buffer saline (PBS). Subsequently,

mice in asthma and BCG groups were immunization and intranasal chal-

lenge with HDM and 10 �g/25 �l of HDM on days 60, 61 and 62

intranasally. The mice were examined for immunoglobuline E (IgE)

response, HDM-specific IgG1 and IgG2a responses, airway hyperrespon-

siveness, the extent of airway remodelling, cytokine pattern and

eosinophilia in bronchoalveolar lavage (BAL).

RESULTS: Comparison of BCG and asthma groups showed statistically

significant differences in goblet cell numbers, thickness of subepithelial

smooth muscle (p<0.01). BCG group were most significantly protected

from airway hyperresponsiveness to methacholine, BAL eosinophilia

(p<0.01), BAL fluid IL-4 levels (p<0.01), serum total IgE (p<0.01) and

HDM-specific IgG1 (p<0.01). No changes were observed in the BAL

fluid IL-10, IL-13, interferon-gamma, Transforming growth factor-�

levels and the thickness of subepithelial fibrosis.

CONCLUSIONS: These data suggest that BCG could be effective in the

chronic changes of airways due to asthma and associated with the induc-

tion of helper T cell type 1 (TH1) immune response.

1079 IgE Immunotherapy Efficiently Induces NeutralizingAntiHuman IgE Antibodies in Primates

Å. Jansson, A. Fuentes, E. Landström, S. Persson, B. Xu; Resistentia

Pharmaceuticals AB, Uppsala, SWEDEN.

RATIONALE: To evaluate the efficacy of an allergen-independent IgE

immunotherapy to induce neutralizing anti-human IgE antibodies in

cynomolgus monkeys.

METHODS: Cynomolgus monkeys were subcutaneously administered

the immunotherapeutic protein (formulated with the aluminum-based

adjuvant Alhydrogel) at the doses 100, 300 and 600 µg at study weeks 0,

2, 4, 6 and 8. Efficacy was evaluated as (i) anti-human IgE titers and (ii)

the ability of serum to inhibit human IgE-mediated mast cell degranu-

lation in vitro. The study was performed as a dose range study with a

kinetic evaluation of the response.

RESULTS: Treatment of cynomolgus monkeys with Resistentia’s IgE

immunotherapy induced pronounced IgG anti-human IgE titers in all ani-

mals. In addition, the induced antibodies markedly inhibited human IgE-

mediated mast cell degranulation in vitro, from 3 up to at least 9 weeks

following primary injection. At a serum dilution of 1/90 and 50 ng human

IgE/ml, all eight animals of the 100 µg dose group responded with a more

than 50 % inhibition at study week 9 compared to pre-immune serum.

One animal out of eight displayed IgE inhibitory capacity already at study

week 3 (12%), five out of eight (62%) at week 5 and seven out of eight

(88%) at week 7.

CONCLUSIONS: We here demonstrate for the first time that treatment

of cynomolgus monkeys with Resistentia’s IgE immunotherapy induces

anti-human IgE antibodies with a pronounced capacity to inhibit human

IgE-mediated mast cell function in vitro. Clinical evaluation (phase I) of

this novel approach to treat IgE-mediated diseases is planned to com-

mence 2006.

Funding: Resistentia Pharmaceuticals AB