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456 Depletion of neutrophils promotes T helper 2 cytokine pathway in murine allergic aspergillosis
296
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454
Abstracts
J ALLERGYCLIN IMMUNOL JANUARY 1996
Effects o f a n A n t i b o d y to I n t e r l e u k i n - 5 in a M u r i n e M o d e l o f A i r w a y S e n s i t i z a t i o n . l~W Gelfand MD. J Schwarze MD. A Oshiba MD. K Bradley. J Loader. G Larsen MD. *R Coffman PhD. E Hamelmann MD, Denver, CO and *Palo Alto, CA Intefleukin-5 (IL-5) is a major stimulus for eosinophils, key cells in the development of airway hyperresponsiveness (AHR) in human bronchial asthma and animal models of AHR. The effect of a neutralizing antibody to murine 1L-5 (TRFK-5) was investigated in a mouse model of airway sensitization. BALB/c mice were sensitized via the airways with ovalbumin (OVA) on 10 consecutive days, leading to production of anti-OVA IgE, enhanced in vitro IL-5 production by local draining lymph node cells (165 pg/ml vs 15 pg/ml in controls) and the development of AHR, measured by electrical field stimulation of tracheal segments comparing the frequencies leading to 50% of the maximum contraction (ESso in Hz). Treatment of mice with TRFK-5 (100 I.tg iv) on days 4, 6 and 8 of the protocol did not affect anti-OVA IgE serum levels or development of immediate cutaneous hypersensitivity (ICH), but markedly reduced numbers of eosinophils in interstitial lung cells (p<0.007), BAL fluid and lung sections, and prevented the develc ~mentof AHR ~ )<0.03). IgE ICH Wheal AHR Eos (EU/ml) responder (ram) (Hz) (xlO6) OVA 45±33 10/12 8.3±3.7 2.1 ~0.4 1.17±0.5 TRFI~ 60+46 9/12 8:t:3.6 3.5±0.33 0.18.+_0.1 These data indicate that: 1) eosinophil inflammation triggered by IL-5 production is essential for the development of AHR in a mouse model of airway sensitization; and 2) treatment of mice with anti-IL5 antibody during ongoing airway sensitization prevents eosinophil accumulation in the lung tissue and development of AHR without affecting allergen-specific IgE-production and ICH.
455
D E N D R I T I C C E L L S AND B C E L L S IN r D e r p2 P R E S E N T A T I O N T O M E M O R Y AND N A I V E T CELLS FROM ATOPIC PATIENTS, EA Taketomi*,MD,PhD; SJ Sung,PhD; JB Slunt, BSc; .AM Smith.PhD; TAE Platts-Mills.MD.PhD: SM Fu. MD. PhD Charlottesville, VA, USA and *Uberlandia, MG, Brazil Previous reports have shown that different types of antigen presenting cells (APC) possess varying capacities in presenting allergens to T cells. B Cells but not monocytes can prime T cells in vitro to produce IL--4. Dendritic cells (DC) are one of the most potent APC. The focus of this study was to compare DC and B cells to present allergens to T cell subsets. The responses of highly purified memory CD45RO+ and naive CD45RA +T cells were examined. In proliferation assays, only memory T cells responded to r Der p2 presented by DC or B cells. The APC capabilities of DC and B cells were equivalent. Similar responses were also observed for the conventional tetanus toxoid antigen. Both memory and naive T ceils gave strong proliferative responses to mitogenie stimulation with PHA. In relation to cytokine secretion, both DC and B cells stimulated memory T ceils to produce IFN-7 in the presence of 1-10/~g/ml of rDer p2, but not at lower concentrations. DC induced naive T cells to produce as much 1FN-7 as memory T cells. In contrast, B ceils did not induce this response. The production of IFN-7 induced by tetanus toxoid in memory and naive T cells was similar to that induced by rDer p2. These results show that DC and B cells were equivalent in presenting Der p2 to memory T cells. However, DC but not B cells were able to induce IFN-7 production in naive T cells stimulated with rDer p2.
456
Ty. 8 Cells A n d P a r a m e t e r s O f A l l e r g i c Disease: R e l a t i o n s h i p T o T o t a l IgE, A t o p y , A n d B a s o p h i l H i s t a m i n e Release. David J. V o l k m a n , Piotr Kuna. Ewa Kuna, and Allen P. Kanlan. Lodz, Poland and Stony Brook, NY. Allergic responses ate strongly correlated with TH2 activation and basophil mleasability. Recent evidence has implicated TT.s cells in the down regulation of TH2. We meu~sured circulating T cells, IgE levels and basophil responses in atopic and non-atopic subjects. T cells were examined for o~,[~ or 7,8 TcR, CD4, CD8, and CD25. Basophils histamine release was u-iggered with MCP-1. Total IgE was quantitated by PRIST. Statistical significance was determined by the Student t-test and correlations were assessed by the Spearman test. Symptomatic atopic subjects when compared to asymptomatic controls had higher numbers of circulating CD25(+) T cells, lower numbers of Tv.8 cells, higher levels of IgE, and greater amounts of lfistamine release from basophils (all p<0.05). T~,s numbers were inversely correlated to the percentage of MCP-1 induced basophil histamine release (p<0.01). Thus, the number of circulating T.r,~ is significantly reduced in allergic individuals and is strongly con'elated to increased basophilic responsiveness. Since THI suppress TH2 cells via INF-T and T~,.~ are strong producers of this lymphokine, T.~,~may modulate allergic responses through a similar mechanism.
Depletion of neutrophils promotes T Helper 2 cytokine pathway in murine allergic aspergillosis P.S Murali PhD, J Q~Q MS, $O Xia MD. RL Coffman PhD. V P Kuruv PhD Milwaukee, WI, Palo Alto, C A A model of Allergic Bmnchopulmonary Aspergillosis (ABPA) developed in Balb/c mice, by repeated exposure toAspergillus fumigatus antigens, exhibits characteristic pulmonary infdlrate with an early influx of neulrophils occurring before a detectable eosinophil predominance. The eosinophilia and elevated IgE in these mice suggest a T helper 2 (TH2) cytokine pathway. Neulrophils offer protection in models of blond-borne infections however, their contributions in this model of ABPA are not known. To study this, the neutrophils were depleted in vivo in a model of ABPA by injecting mice (n=5) with RB6-8C5, a monoclonal antibody specific for mature routine neutrophils. A group of mice (n=5) not receiving RB6-8C5 served as controls. Serum lgE, Interleukin-2 (IL-2), IL.-4 and IL-5 produced in vitro by spleen cells were measured by ELISA while eosinophil pcroxidase (EPO) levels were estimated colorimetrically. Serum IgE levels 01g/ml) were significantly elevated in RB6-8C5 injected mice (108.1-+1.2, P<0.001) compared to controls (68.0-k6.5). Spleen cell supematants from mice given RB6-8C5, demonswated elevated levels of IL-4 (pg/ml; 108_+8vs 81+_3,P<0.02) and IL-5 (pg/ml; 838_+115 vs not detectable) but not IL-2 (U/ml; 1A64-+0.13 vs 2.624_+0.605). Significantly elevated EPO levels (Optical Density, 0.556_+0.05 vs 0.328_+0.03, P<0.01) were detected in bone marrow cells from these mice. We conclude that depletion of neutrophils leads to further enhancement of an existing TH2 cytokine pathway in this model of ABPA.
453
454
Abstracts
J ALLERGYCLIN IMMUNOL JANUARY 1996
Effects o f a n A n t i b o d y to I n t e r l e u k i n - 5 in a M u r i n e M o d e l o f A i r w a y S e n s i t i z a t i o n . l~W Gelfand MD. J Schwarze MD. A Oshiba MD. K Bradley. J Loader. G Larsen MD. *R Coffman PhD. E Hamelmann MD, Denver, CO and *Palo Alto, CA Intefleukin-5 (IL-5) is a major stimulus for eosinophils, key cells in the development of airway hyperresponsiveness (AHR) in human bronchial asthma and animal models of AHR. The effect of a neutralizing antibody to murine 1L-5 (TRFK-5) was investigated in a mouse model of airway sensitization. BALB/c mice were sensitized via the airways with ovalbumin (OVA) on 10 consecutive days, leading to production of anti-OVA IgE, enhanced in vitro IL-5 production by local draining lymph node cells (165 pg/ml vs 15 pg/ml in controls) and the development of AHR, measured by electrical field stimulation of tracheal segments comparing the frequencies leading to 50% of the maximum contraction (ESso in Hz). Treatment of mice with TRFK-5 (100 I.tg iv) on days 4, 6 and 8 of the protocol did not affect anti-OVA IgE serum levels or development of immediate cutaneous hypersensitivity (ICH), but markedly reduced numbers of eosinophils in interstitial lung cells (p<0.007), BAL fluid and lung sections, and prevented the develc ~mentof AHR ~ )<0.03). IgE ICH Wheal AHR Eos (EU/ml) responder (ram) (Hz) (xlO6) OVA 45±33 10/12 8.3±3.7 2.1 ~0.4 1.17±0.5 TRFI~ 60+46 9/12 8:t:3.6 3.5±0.33 0.18.+_0.1 These data indicate that: 1) eosinophil inflammation triggered by IL-5 production is essential for the development of AHR in a mouse model of airway sensitization; and 2) treatment of mice with anti-IL5 antibody during ongoing airway sensitization prevents eosinophil accumulation in the lung tissue and development of AHR without affecting allergen-specific IgE-production and ICH.
455
D E N D R I T I C C E L L S AND B C E L L S IN r D e r p2 P R E S E N T A T I O N T O M E M O R Y AND N A I V E T CELLS FROM ATOPIC PATIENTS, EA Taketomi*,MD,PhD; SJ Sung,PhD; JB Slunt, BSc; .AM Smith.PhD; TAE Platts-Mills.MD.PhD: SM Fu. MD. PhD Charlottesville, VA, USA and *Uberlandia, MG, Brazil Previous reports have shown that different types of antigen presenting cells (APC) possess varying capacities in presenting allergens to T cells. B Cells but not monocytes can prime T cells in vitro to produce IL--4. Dendritic cells (DC) are one of the most potent APC. The focus of this study was to compare DC and B cells to present allergens to T cell subsets. The responses of highly purified memory CD45RO+ and naive CD45RA +T cells were examined. In proliferation assays, only memory T cells responded to r Der p2 presented by DC or B cells. The APC capabilities of DC and B cells were equivalent. Similar responses were also observed for the conventional tetanus toxoid antigen. Both memory and naive T ceils gave strong proliferative responses to mitogenie stimulation with PHA. In relation to cytokine secretion, both DC and B cells stimulated memory T ceils to produce IFN-7 in the presence of 1-10/~g/ml of rDer p2, but not at lower concentrations. DC induced naive T cells to produce as much 1FN-7 as memory T cells. In contrast, B ceils did not induce this response. The production of IFN-7 induced by tetanus toxoid in memory and naive T cells was similar to that induced by rDer p2. These results show that DC and B cells were equivalent in presenting Der p2 to memory T cells. However, DC but not B cells were able to induce IFN-7 production in naive T cells stimulated with rDer p2.
456
Ty. 8 Cells A n d P a r a m e t e r s O f A l l e r g i c Disease: R e l a t i o n s h i p T o T o t a l IgE, A t o p y , A n d B a s o p h i l H i s t a m i n e Release. David J. V o l k m a n , Piotr Kuna. Ewa Kuna, and Allen P. Kanlan. Lodz, Poland and Stony Brook, NY. Allergic responses ate strongly correlated with TH2 activation and basophil mleasability. Recent evidence has implicated TT.s cells in the down regulation of TH2. We meu~sured circulating T cells, IgE levels and basophil responses in atopic and non-atopic subjects. T cells were examined for o~,[~ or 7,8 TcR, CD4, CD8, and CD25. Basophils histamine release was u-iggered with MCP-1. Total IgE was quantitated by PRIST. Statistical significance was determined by the Student t-test and correlations were assessed by the Spearman test. Symptomatic atopic subjects when compared to asymptomatic controls had higher numbers of circulating CD25(+) T cells, lower numbers of Tv.8 cells, higher levels of IgE, and greater amounts of lfistamine release from basophils (all p<0.05). T~,s numbers were inversely correlated to the percentage of MCP-1 induced basophil histamine release (p<0.01). Thus, the number of circulating T.r,~ is significantly reduced in allergic individuals and is strongly con'elated to increased basophilic responsiveness. Since THI suppress TH2 cells via INF-T and T~,.~ are strong producers of this lymphokine, T.~,~may modulate allergic responses through a similar mechanism.
Depletion of neutrophils promotes T Helper 2 cytokine pathway in murine allergic aspergillosis P.S Murali PhD, J Q~Q MS, $O Xia MD. RL Coffman PhD. V P Kuruv PhD Milwaukee, WI, Palo Alto, C A A model of Allergic Bmnchopulmonary Aspergillosis (ABPA) developed in Balb/c mice, by repeated exposure toAspergillus fumigatus antigens, exhibits characteristic pulmonary infdlrate with an early influx of neulrophils occurring before a detectable eosinophil predominance. The eosinophilia and elevated IgE in these mice suggest a T helper 2 (TH2) cytokine pathway. Neulrophils offer protection in models of blond-borne infections however, their contributions in this model of ABPA are not known. To study this, the neutrophils were depleted in vivo in a model of ABPA by injecting mice (n=5) with RB6-8C5, a monoclonal antibody specific for mature routine neutrophils. A group of mice (n=5) not receiving RB6-8C5 served as controls. Serum lgE, Interleukin-2 (IL-2), IL.-4 and IL-5 produced in vitro by spleen cells were measured by ELISA while eosinophil pcroxidase (EPO) levels were estimated colorimetrically. Serum IgE levels 01g/ml) were significantly elevated in RB6-8C5 injected mice (108.1-+1.2, P<0.001) compared to controls (68.0-k6.5). Spleen cell supematants from mice given RB6-8C5, demonswated elevated levels of IL-4 (pg/ml; 108_+8vs 81+_3,P<0.02) and IL-5 (pg/ml; 838_+115 vs not detectable) but not IL-2 (U/ml; 1A64-+0.13 vs 2.624_+0.605). Significantly elevated EPO levels (Optical Density, 0.556_+0.05 vs 0.328_+0.03, P<0.01) were detected in bone marrow cells from these mice. We conclude that depletion of neutrophils leads to further enhancement of an existing TH2 cytokine pathway in this model of ABPA.