1 Department of Biochemistry and Molecular Biology, Mayo Clinic Scottsdale, Scottsdale, Arizona 85259; and 2 Genetics Institute, Incorporated, Cambridge, Massachusetts 02140
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ABSTRACT |
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Lymphocyte and/or eosinophil
recruitment is dependent on the sequential interactions between
adhesion molecules expressed on activated endothelial cells and both
leukocyte subtypes. Endothelial P- and E-selectins mediate tethering
and rolling of leukocytes through interactions with P-selectin
glycoprotein ligand-1 (PSGL-1), and diapedesis subsequently occurs by
engagement of endothelial vascular cell adhesion molecule-1 and CD49d
(4-integrins). The anti-inflammatory potential of
interfering with these adhesive interactions was assessed with an
ovalbumin challenge mouse model of asthma. Administration of a soluble
form of PSGL-1 reduced eosinophils (80%) and lymphocytes (50%) in
bronchoalveolar lavage fluid without affecting epithelial changes or
airway hyperreactivity (AHR). In contrast, although administration of
anti-CD49d monoclonal antibodies (PS/2) resulted in similar reductions
in eosinophils (75%) and lymphocytes (50%), PS/2 reduced and
abolished mucous cell metaplasia and AHR, respectively.
Administration of both PSGL-1 and PS/2 had the additive effect of
eliminating eosinophils from the airways (96% decrease), with few or
no additional reductions (relative to PS/2 administration alone) in
lymphocyte recruitment, mucous cell metaplasia, or AHR. These data show
that eosinophils and lymphocytes differentially utilize adhesive
interactions during recruitment and that the inhibition of AHR is
independent of this recruitment.
airway hyperreactivity; 4-integrin; P-selectin
glycoprotein ligand-1
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INTRODUCTION |
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ALLERGIC AIRWAY INFLAMMATION is characterized by airway and peribronchial leukocyte accumulation that consists of eosinophils and lymphocytes. It is widely believed that lymphocytes, through the production of Th2 cytokines [i.e., interleukin (IL)-4, -5 and -13], mediate the recruitment and activation of eosinophils (34). In allergic airway diseases such as asthma, eosinophils have been hypothesized to secrete toxic granule proteins and other inflammatory mediators that contribute to the hallmark features of the disease, such as excess mucus production and airway dysfunction (8). Sensitization and aerosol challenge of mice with ovalbumin (Ova) is a common and well-characterized method used to produce phenotypic changes associated with human asthma, including mucous cell metaplasia, airway hyperreactivity (AHR), and accumulation of eosinophils and lymphocytes in the lung (7, 10, 11, 24). The protocols used to generate these phenotypes vary in timing and the number of sensitizations and challenges required to elicit these phenotypes. Although specific studies may be limited because they present data from a single strain of mice under one set of conditions, these studies nonetheless display features of human asthma and thus constitute relevant models of allergic pulmonary inflammation.
The current paradigm of eosinophil-mediated inflammation in response to
allergen involves the increased production, maturation, and release of
eosinophils from the marrow into the blood and increased adhesion to
and migration through the capillary endothelium. The cell-cell
interactions that mediate selective eosinophil migration are complex,
overlapping processes controlled by families of cytokines, adhesion
molecules, and chemoattractants (32). Leukocyte adhesion and migration through the vascular endothelium involve the sequential tethering, rolling, and firm adhesion along the endothelium followed by
diapedesis between endothelial cells and directed migration into the
tissue (27). The initial binding and subsequent firm adhesion of eosinophils have been shown to be mediated by binding to
P-selectin and vascular cell adhesion molecule-1 (VCAM-1) receptors on
endothelial cells, respectively (14). Eosinophils bind to these receptors, predominantly through their cell surface ligands P-selectin glycoprotein ligand-1 (PSGL-1) (29) and
heterodideric integrins comprised of the 4-subunit
(CD49) (33).
Previous studies with P-selectin-deficient mice have demonstrated an important role for P-selectin in allergic pulmonary inflammation, including tissue eosinophilia (5, 7) and AHR (7). Similarly, studies have established a role for CD49d in pulmonary inflammation in several species including sheep (2), guinea pigs (23), and mice (19). Furthermore, CD49d-blocking antibodies have also been shown to attenuate AHR after allergen challenge in these species (2, 11, 23).
The tethering, rolling, and adhesion of leukocytes were initially characterized as processes distinctly regulated by unique families of endothelial cell receptors (i.e., selectins and immunoglobulin gene superfamily adhesion receptors) (27); however, increasing evidence suggests that there is an overlap in function of these receptors in the tethering and firm adhesion of eosinophils to the endothelium (12, 20). The objective of this study was to determine whether simultaneously blocking PSGL-1/P-selectin and CD49d/VCAM-1 receptor-ligand interactions in a murine model of allergic pulmonary inflammation significantly reduces observed leukocyte recruitment, mucous cell metaplasia, and AHR compared with the disruption of either interaction individually. The data presented demonstrate that intravenous coadministration of a soluble recombinant form of human PSGL-1 (rsPSGL-Ig) (28) and rat anti-mouse CD49d IgG (PS/2) before allergen challenge had the additive effect of eliminating airway and parenchymal eosinophilia, without additional reductions of recruited lymphocytes, compared with either antagonist administered alone. Administration of rsPSGL-Ig had no effect on mucous cell metaplasia or AHR. In contrast, PS/2 significantly reduced mucous cell metaplasia and abolished AHR. Coadministration of these antagonists further inhibited the development of mucous cells along the airways and also abolished AHR. These observations suggest that blockade of CD49d reduces allergic pulmonary pathologies through a mechanism(s) independent of its effects on leukocyte recruitment.
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MATERIALS AND METHODS |
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Experimental design. BALB/cJ mice (female, 6-8 wks; Jackson Laboratories, Bar Harbor, ME) were sensitized by an intraperitoneal injection (100 µl) of 20 µg of chicken Ova (Sigma, St. Louis, MO) emulsified in 2 mg of Imject Alum [Al(OH)3-Mg(OH)2] (Pierce, Rockford, IL) on days 0 and 14. Mice were subsequently challenged with an aerosol generated from 1% Ova in saline or saline alone for 20 min by ultrasonic nebulization (DeVilbiss, Somerset, PA) on days 24, 25, and 26. Assessments of inflammation and pulmonary pathology, including mucous cell metaplasia and AHR, were made on day 28 (n = 8-12 mice/group). rsPSGL-Ig is a recombinant, chimeric construct containing the 47 NH2-terminal amino acid sequence of human PSGL-1 fused to a mutated human IgG1 Fc heavy chain fragment (Genetics Institute, Cambridge, MA). The molecule is predominantly dimeric and has been demonstrated to have binding activity to P-selectin in vitro (26). rsPSGL-Ig and/or PS/2 (American Type Culture Collection, Manassas, VA) was administered via the tail vein 3 h before each aerosol challenge. The optimal doses for in vivo neutralization of murine allergic inflammation (rsPSGL-Ig, 100 µg in 50 µl; PS/2, 200 µg in 50 µl) were determined in earlier studies (11, 19, 28). All mice were maintained in microisolator cages housed in a specific pathogen-free animal facility. The sentinel cages within this animal colony were negative for viral antibodies and the presence of known mouse pathogens. Protocols and studies involving animals were conducted in accordance with National Institutes of Health and Mayo Clinic Foundation guidelines.
Assessment of allergic inflammation.
Allergic inflammation was assessed on day 28 by enumerating
peripheral blood, lung, and bronchoalveolar lavage (BAL) fluid leukocytes. Assessments of blood leukocytes were determined by recovering blood from the tail vein and removing contaminating red
blood cells by hypotonic lysis. Total white blood cell counts were
quantified with a hemacytometer, and cell differentials were performed
on Wright-stained blood films by counting 300 cells. Lungs were
lavaged three times with 0.5 ml of Hanks' balanced salt solution
(HBSS; GIBCO BRL, Life Technologies, Gaithersburg, MD) containing 2%
FCS. Individual BAL fluid returns were pooled and stored at 4°C until
the cells were counted. Total cell counts were determined with a
hemacytometer, and cell differentials were performed on Wright-stained
cytospin slides (Cytospin 3, Shandon Scientific, Pittsburgh, PA) by
counting
300 cells.
Mucous cell metaplasia. Mucous cell development along the airway epithelium was quantified in paraffin-embedded tissue sections (4 µm) stained with periodic acid-Schiff reagent. Parasaggital sections (n = 5 mice/group) were analyzed by bright-field microscopy with an image analysis software program (ImagePro Plus, Media Cybernetics, Silver Spring, MD) to derive an airway mucus index that was reflective of both the amount of mucus per airway and the number of airways affected. The airway mucus index was calculated by summing the ratio of the periodic acid-Schiff-positive epithelial area to the total epithelial area per section and dividing by the number of airways per section.
Measurements of AHR. AHR was determined by inducing airflow obstruction with a methacholine aerosol. Total pulmonary airflow in unrestrained conscious mice was estimated with a whole body plethysmograph (Buxco Electronics, Troy, NY). Pressure differences between a chamber containing the mice and a reference chamber were used to extrapolate minute volume, tidal volume, breathing frequency, and enhanced paused (Penh). Penh is a dimensionless parameter that is a function of total pulmonary airflow in mice during the respiratory cycle. This parameter closely correlates with airway resistance in BALB/c mice as measured by traditional invasive techniques performed with ventilated mice (10).
Statistical analysis. Data are means ± SE. Statistical analysis was performed on parametric data with t-tests, with differences between means considered significant when P < 0.05.
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RESULTS |
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rsPSGL-Ig and PS/2 administration differentially reduce leukocyte
infiltration of the lung.
Ova-challenged mice exhibited an increase in both airway eosinophils
and lymphocytes recovered in the BAL fluid 48 h after the
last challenge (Fig. 1, A and
B, respectively). Administration of either rsPSGL-Ig
or PS/2 before the Ova challenges resulted in a significant reduction
in airway eosinophils (80 and 76%, respectively) recovered in the BAL
fluid (Fig. 1A). Moreover, administration of rsPSGL-Ig and
PS/2 in combination further reduced eosinophil accumulation (~95%
reduction) in the BAL fluid compared with PS/2 alone (Fig.
1B). In contrast, although treatment with either rsPSGL-Ig
or PS/2 alone significantly reduced (~50%) the number of lymphocytes
in the BAL fluid (Fig. 1B), treatment with both rsPSGL-Ig
and PS/2 did not further reduce the number of lymphocytes recovered in
the BAL fluid. The administration of either antagonist alone or in
combination had no effect on BAL fluid leukocyte counts in
saline-challenged mice.
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Peripheral blood eosinophilia is augmented as a consequence
of administering rsPSGL-Ig and/or PS/2.
Relative to saline control mice, Ova-challenged mice exhibited a
significant increase in peripheral blood eosinophils (73 ± 17 vs.
262 ± 25 cells/mm3) 48 h after the last
challenge (Fig. 4). Administration of
rsPSGL-Ig or PS/2 increased eosinophil accumulation in the blood of
Ova-challenged mice (362 ± 55 and 400 ± 27 cells/mm3, respectively), and treatment with both
antagonists together further increased blood eosinophil counts
(539 ± 56 cells/mm3). No effects on peripheral blood
eosinophil counts were observed in saline-challenged mice treated with
rsPSGL-Ig and/or PS/2.
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Coadministration of rsPSGL-Ig and PS/2 had little additional effect
on airway mucous cell development compared with PS/2 alone.
Mice sensitized and challenged with Ova developed several
histopathologies in the lung, including increased epithelial cell thickness and mucous cell metaplasia along the conducting
airways (Figs. 5, A vs.
B, and 6).
Administration of rsPSGL-Ig had no effect on the
development of mucous cells along the airways (Figs. 5D and
6), whereas PS/2 treatment alone inhibited the production of mucus by
the epithelium (Figs. 5F and 6). This effect was enhanced by
the administration of both antagonists in combination (Figs. 5H and 6).
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Blockade of CD49d obviates antigen-induced AHR.
Mice sensitized and challenged with Ova demonstrated an increased
reactivity (i.e., AHR) to methacholine provocation compared with
saline-challenged mice. This AHR was unaffected by pretreatment with
rsPSGL-Ig (Fig. 7A). In
contrast, treatment with PS/2 alone completely inhibited AHR in
Ova-challenged mice (Fig. 7B). Furthermore, pretreatment
with both antagonists in combination also abolished AHR (Fig.
7C).
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DISCUSSION |
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The migration of leukocytes from the vasculature into the lung
tissue in response to allergen provocation involves tethering, rolling,
and firm adhesion to the endothelial cell surface. These processes are
controlled by cell surface receptor-ligand interactions that include
the binding of leukocyte-expressed PSGL-1 with endothelial cell
P-selectin and the binding of leukocyte CD49d-containing integrins with
VCAM-1 (27). PSGL-1 is a sialomucin consisting of two
120-kDa subunits expressed on the cell surface of most leukocytes,
including eosinophils and T cells (18), and is thought to
be the principal ligand responsible for eosinophil tethering on
endothelial cell-expressed P-selectin (20, 29). The
importance of P-selectin in eosinophil and lymphocyte recruitment has
been established with P-selectin-deficient mice (5, 7, 9). These studies showed that in Ova-induced models of allergic airway inflammation, the onset and magnitude of leukocyte accumulation in the
airways were inhibited in P-selectin-deficient compared with wild-type
mice. This has also been demonstrated with P-selectin antibodies in in
vitro eosinophil adhesion assays (20, 30). CD49d
(4-integrin) is the common subunit of two cell surface heterodimers (
4
1 and
4
7) expressed on leukocytes that mediate cell-cell adhesion to VCAM-1 and cell-matrix adhesion to fibronectin (17). The importance of CD49d expression on eosinophils
and lymphocytes and its role in Ova-induced allergic inflammation has
previously been established by antibody depletion studies in several
species (19, 23, 25). These studies demonstrated that
inhibition of CD49d with blocking antibodies inhibited both eosinophil
and lymphocyte accumulation in the lung, with a concomitant increase in
the circulating levels of these cells.
The incomplete inhibition of pulmonary inflammation commonly observed
by blocking either P-selectin binding (tethering) or VCAM-1 binding
(adhesion) suggests that there are other mechanisms for tethering and
adhesion (i.e., E-selectin, alternate integrin-adhesion molecule
interactions) and/or overlapping functions between P-selectin and
VCAM-1 (i.e., VCAM-1 can support initial attachment of leukocytes to
the endothelium, and P-selectin is sufficient to mediate some degree of
adhesion to the endothelium). Previous evidence demonstrating that
initial attachment and subsequent firm adhesion are not independently controlled is extensive. 1) Eosinophil adhesion to nasal
polyp endothelium is P-selectin dependent and can occur independent of
VCAM-1 (30). Conversely, eosinophils can tether via CD49d to purified VCAM-1 under flow conditions (3), and
CD49d was shown to mediate the initial attachment of eosinophils to
tumor necrosis factor- (TNF-
)-activated endothelium under flow
conditions (31). 2) Hickey et al.
(12) showed that residual eosinophil tethering was
completely abolished by CD49d-blocking antibodies in
P-selectin-deficient mice. 3) Overlapping and cooperative
effects between these two receptors have also been demonstrated in
double-knockout P- and E-selectin-deficient mice (13) and
in in vitro assays with neutralization antibodies and IL-4-stimulated
endothelium (20). Collectively, these experiments do not
exclude the contribution of intercellular adhesion molecule (ICAM)/CD18
interactions, also known to mediate adhesion of eosinophils to vascular
endothelium (5); however, these studies suggest that
interfering with both P-selectin and VCAM-1 effectively eliminates
eosinophilia because of the greater specificity toward eosinophils (as
opposed to neutrophils) displayed by these two receptors
(21). The data presented here (BAL fluid and collagenase
digestion of lung tissue) support the idea that P-selectin interactions
are required for leukocyte accumulation in allergic airway inflammation
and also demonstrate that administration of rsPSGL-Ig is equally
effective as a blockade of CD49d. Interestingly, simultaneous
inhibition of both interactions effectively eliminated (96% reduction)
BAL fluid eosinophilia, likely due to the inability of circulating
cells to interact with the endothelium. In contrast, a further
inhibition of lymphocytes was not observed after the administration of
both antagonists, suggesting that lymphocytes are less dependent on
PSGL-1 and CD49d interactions with the vascular endothelium in order to
accumulate in the lung during allergic inflammation. In addition to
direct effects on relative adhesive interactions, the differential
accumulation of eosinophils and lymphocytes may also reflect
differences in systemic recirculation (i.e., lymphocytes are able to
leave mucosal tissues and return to the circulation, whereas
eosinophils cannot recirculate) or in the local expansion of
lymphocytes that occurs within the lung parenchyma of allergen-exposed
mice (6).
Mucous cell metaplasia and AHR are two primary pathological and
physiological abnormalities associated with allergic pulmonary inflammation. Our results clearly demonstrate that inhibition of
leukocyte recruitment does not correlate with the obviation of these
allergic pathophysiologies. Equivalent inhibition of eosinophil and
lymphocyte accumulation by blocking distinct receptor-ligand interactions produced different effects on mucous cell development and
AHR. Furthermore, only a nominal further decrease in mucous cell
development was observed when eosinophilia was abolished with both
antagonists in combination. These differential effects on pulmonary
pathologies by inhibition of 4-receptor-ligand
interactions alone suggest that these interactions mediate a
generalized effect on the leukocyte activation state or perhaps mediate
specific effects on unique leukocyte subpopulations in the lungs. The
role of P-selectin/PSGL-1 appears to be limited to mediating
extravasation from the circulation because leukocytes entering the
tissue under conditions in which PSGL-1 binding was limited maintained
the capacity to become activated, as evidenced by the development of
mucous cell metaplasia and AHR. Conversely, the
4-integrin system appears to have dual roles in allergic
airway disease. In addition to mediating leukocyte recruitment from the
circulation, these data demonstrate that
4-integrin
activation is necessary for the development of mucous cell metaplasia
and AHR. The mechanism by which and the extent to which CD49d binding
mediates activation and/or survival of either eosinophils or
lymphocytes remain problematic. However, CD49d binding of extravascular
leukocytes to other cells and/or extracellular matrix components may be
required for the functional release of mediators that subsequently lead
to AHR. This is supported by data that demonstrate that eosinophils are activated, as assessed by increased survival in vitro, after CD49d binding to fibronectin (4) and by studies (2,
22) suggesting that eosinophil activation as determined by
granule protein release rather than the number of cells recruited is
associated with the development of bronchial hyperreactivity in sheep
and guinea pigs. Furthermore, small-molecule peptide inhibitors of
CD49d, which selectively block the fibronectin binding domain without
interfering with VCAM binding, effectively inhibited the early- and
late-phase airway responses in allergic sheep (1, 16). In
addition, Henderson et al. (11) have shown inhibition of
Th2 cytokines (IL-4 and IL-5) in the BAL fluid of allergic mice after
intranasal administration of CD49d antibody, suggesting that T-cell
activation and associated functions depend on CD49d interactions.
The different effects on eosinophil and lymphocyte inhibition observed in our study may also be a consequence of perturbing unique subsets of the heterogeneous lymphocyte populations in the lung. Although the total lymphocyte accumulation is equally reduced after rsPSGL-Ig or PS/2 treatment, one or more subtypes that contribute to the observed pulmonary pathologies may have been preferentially inhibited by PS/2. For example, Nakajima and colleagues (19) demonstrated an equal reduction (~75%) in CD4+ and CD8+ T cells after PS/2 administration in Ova-challenged mice, whereas De Sanctis et al. (7) reported a 40% reduction in CD4+ subsets without a change in CD8+ T cells in Ova-challenged P-selectin-deficient mice. Whether these different responses can be attributed to the selective inhibition of unique T-cell subpopulations remains to be determined.
These data demonstrate that administration of rsPSGL-Ig is as effective as CD49d blockade in reducing eosinophil and lymphocyte accumulation in the lungs of Ova-challenged mice, whereas, in combination, the antagonists completely block eosinophil accumulation without additional effects on the accumulation of lymphocytes. This suggests that leukocyte subtypes capable of utilizing both adhesive interactions nonetheless migrate to the lung via independent mechanisms. Moreover, blockade of these cell adhesion interactions also has different effects on the inhibition of airway mucous cell development and AHR, demonstrating that inhibition of these pathologies occurs independent of leukocyte recruitment. These findings indicate that the extent of activation is critical to the development of mucous cell metaplasia and AHR and may represent alternative therapeutic targets of pulmonary pathologies associated with chronic allergic inflammation.
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ACKNOWLEDGEMENTS |
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We acknowledge the technical assistance of the Mayo Clinic Scottsdale Histology Facility (Anita Jennings, Director) and the Mayo Clinic Scottsdale Graphic Arts Department (Marv Ruona). We also thank Edith Hines and Katie O'Neill for excellent technical assistance and Linda Mardel, research program assistant.
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FOOTNOTES |
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This study was supported by funds from the Mayo Clinic Foundation; National Heart, Lung, and Blood Institute (NHLBI) Grant HL-60793-01S (to N. A. Lee), NHLBI Training Grant HL-07897 (to M. T. Borchers); and an individual National Research Service Award (to J. Crosby).
Address for reprint requests and other correspondence: J. J. Lee, Dept. of Biochemistry and Molecular Biology, SCJMRB-Research, Mayo Clinic Scottsdale, 13400 E. Shea Blvd., Scottsdale, AZ 85259 (E-mail: jlee{at}mayo.edu).
The costs of publication of this article were defrayed in part by the payment of page charges. The article must therefore be hereby marked "advertisement" in accordance with 18 U.S.C. Section 1734 solely to indicate this fact.
Received 29 August 2000; accepted in final form 1 November 2000.
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REFERENCES |
---|
![]() ![]() ![]() ![]() ![]() ![]() ![]() |
---|
1.
Abraham, WM,
Ahmed A,
Sielczak MW,
Narita M,
Arrhenius T,
and
Elices MJ.
Blockade of late-phase airway responses and airway hyperresponsiveness in allergic sheep with a small-molecule peptide inhibitor of VLA-4.
Am J Respir Crit Care Med
156:
696-703,
1997
2.
Abraham, WM,
Sielczak MW,
Ahmed A,
Cortes A,
Lauredo IT,
Kim J,
Pepinsky B,
Benjamin CD,
Leone DR,
Lobb RR,
and
Weller PF.
Alpha 4-integrins mediate antigen-induced late bronchial responses and prolonged airway hyperresponsiveness in sheep.
J Clin Invest
93:
776-787,
1994[ISI][Medline].
3.
Alon, R,
Kassner PD,
Carr MW,
Finger EB,
Hemler ME,
and
Springer TA.
The integrin VLA-4 supports tethering and rolling in flow on VCAM-1.
J Cell Biol
128:
1243-1253,
1995[Abstract].
4.
Anwar, AR,
Moqbel R,
Walsh GM,
Kay AB,
and
Wardlaw AJ.
Adhesion to fibronectin prolongs eosinophil survival.
J Exp Med
177:
839-843,
1993[Abstract].
5.
Broide, DH,
Sullivan S,
Gifford T,
and
Sriramarao P.
Inhibition of pulmonary eosinophilia in P-selectin- and ICAM-1-deficient mice.
Am J Respir Cell Mol Biol
18:
218-225,
1998
6.
Chvatchko, Y,
Kosco-Vilbois MH,
Herren S,
Lefort J,
and
Bonnefoy JY.
Germinal center formation and local immunoglobulin E (IgE) production in the lung after an airway antigenic challenge.
J Exp Med
184:
2353-2360,
1996
7.
De Sanctis, GT,
Wolyniec WW,
Green FH,
Qin S,
Jiao A,
Finn PW,
Noonan T,
Joetham AA,
Gelfand E,
Doerschuk CM,
and
Drazen JM.
Reduction of allergic airway responses in P-selectin-deficient mice.
J Appl Physiol
83:
681-687,
1997
8.
Gleich, GJ.
The eosinophil and bronchial asthma: current understanding.
J Allergy Clin Immunol
85:
422-436,
1990[ISI][Medline].
9.
Gonzalo, JA,
Lloyd CM,
Kremer L,
Finger E,
Martinez AC,
Siegelman MH,
Cybulsky M,
and
Gutierrez-Ramos JC.
Eosinophil recruitment to the lung in a murine model of allergic inflammation. The role of T cells, chemokines, and adhesion receptors.
J Clin Invest
98:
2332-2345,
1996
10.
Hamelmann, E,
Schwarze J,
Takeda K,
Oshiba A,
Larsen GL,
Irvin CG,
and
Gelfand EW.
Noninvasive measurement of airway responsiveness in allergic mice using barometric plethysmography.
Am J Respir Crit Care Med
156:
766-775,
1997
11.
Henderson, WR, Jr,
Chi EY,
Albert RK,
Chu SJ,
Lamm WJE,
Rochon Y,
Jonas M,
Christie PE,
and
Harlan JM.
Blockade of CD49D (alpha4 integrin) on intrapulmonary but not circulating leukocytes inhibits airway inflammation and hyperresponsiveness in a mouse model of asthma.
J Clin Invest
100:
3083-3092,
1997
12.
Hickey, MJ,
Granger DN,
and
Kubes P.
Molecular mechanisms underlying IL-4-induced leukocyte recruitment in vivo: a critical role for the alpha 4 integrin.
J Immunol
163:
3441-3448,
1999
13.
Kanwar, S,
Bullard DC,
Hickey MJ,
Smith CW,
Beaudet AL,
Wolitzky BA,
and
Kubes P.
The association between alpha4-integrin, P-selectin, and E-selectin in an allergic model of inflammation.
J Exp Med
185:
1077-1087,
1997
14.
Kitayama, J,
Fuhlbrigge RC,
Puri KD,
and
Springer TA.
P-selectin, L-selectin, and alpha 4 integrin have distinct roles in eosinophil tethering and arrest on vascular endothelial cells under physiological flow conditions.
J Immunol
159:
3929-3939,
1997[Abstract].
15.
Lee, JJ,
McGarry MP,
Farmer SC,
Denzler KL,
Larson KA,
Carrigan T,
Brenneise IE,
Horton MA,
Haczku A,
Gelfand EW,
Leikauf GD,
and
Lee NA.
Interleukin-5 expression in the lung epithelium of transgenic mice leads to pulmonary changes pathognomonic of asthma.
J Exp Med
185:
2143-2156,
1997
16.
Lin, K,
Ateeq HS,
Hsiung SH,
Chong LT,
Zimmerman CN,
Castro A,
Lee WC,
Hammond CE,
Kalkunte S,
Chen LL,
Pepinsky RB,
Leone DR,
Sprague AG,
Abraham WM,
Gill A,
Lobb RR,
and
Adams SP.
Selective, tight-binding inhibitors of integrin 4
1 that inhibit allergic airway responses.
J Med Chem
42:
920-934,
1999[ISI][Medline].
17.
Lobb, RR,
Pepinsky B,
Leone DR,
and
Abraham WM.
The role of alpha 4 integrins in lung pathophysiology.
Eur Respir J Suppl
22:
104s-108s,
1996[Medline].
18.
McEver, RP,
and
Cummings RD.
Perspectives series: cell adhesion in vascular biology. Role of PSGL-1 binding to selectins in leukocyte recruitment.
J Clin Invest
100:
485-491,
1997
19.
Nakajima, H,
Sano H,
Nishimura T,
Yoshida S,
and
Iwamoto I.
Role of vascular cell adhesion molecule 1/very late activation antigen 4 and intercellular adhesion molecule 1/lymphocyte function-associated antigen 1 interactions in antigen-induced eosinophil and T cell recruitment into the tissue.
J Exp Med
179:
1145-1154,
1994[Abstract].
20.
Patel, KD.
Eosinophil tethering to interleukin-4-activated endothelial cells requires both P-selectin and vascular cell adhesion molecule-1.
Blood
92:
3904-3911,
1998
21.
Patel, KD,
and
McEver RP.
Comparison of tethering and rolling of eosinophils and neutrophils through selectins and P-selectin glycoprotein ligand-1.
J Immunol
159:
4555-4565,
1997[Abstract].
22.
Pretolani, M,
Ruffie C,
Joseph D,
Campos MG,
Church MK,
Lefort J,
and
Vargaftig BB.
Role of eosinophil activation in the bronchial reactivity of allergic guinea pigs.
Am J Respir Crit Care Med
149:
1167-1174,
1994[Abstract].
23.
Pretolani, M,
Ruffie C,
Lapa e Silva JR,
Joseph D,
Lobb RR,
and
Vargaftig BB.
Antibody to very late activation antigen 4 prevents antigen-induced bronchial hyperreactivity and cellular infiltration in the guinea pig airways.
J Exp Med
180:
795-805,
1994[Abstract].
24.
Renz, H,
Smith HR,
Henson JE,
Ray BS,
Irvin CG,
and
Gelfand EW.
Aerosolized antigen exposure without adjuvant causes increased IgE production and increased airway responsiveness in the mouse.
J Allergy Clin Immunol
89:
1127-1138,
1992[ISI][Medline].
25.
Richards, IM,
Kolbasa KP,
Hatfield CA,
Winterrowd GE,
Vonderfecht SL,
Fidler SF,
Griffin RL,
Brashler JR,
Krzesicki RF,
Sly LM,
Ready KA,
Staite ND,
and
Chin JE.
Role of very late activation antigen-4 in the antigen-induced accumulation of eosinophils and lymphocytes in the lungs and airway lumen of sensitized brown Norway rats.
Am J Respir Cell Mol Biol
15:
172-183,
1996[Abstract].
26.
Sako, D,
Chang XJ,
Barone KM,
Vachino G,
White HM,
Shaw G,
Veldman GM,
Bean KM,
Ahern TJ,
Furie B,
Cumming DA,
and
Larson GR.
Expression cloning of a functional glycoprotein ligand for P-selectin.
Cell
75:
1179-1186,
1993[ISI][Medline].
27.
Springer, TA.
Traffic signals for lymphocyte recirculation and leukocyte emigration: the multistep paradigm.
Cell
76:
301-314,
1994[ISI][Medline].
28.
Strauss, EC,
Larson KA,
Brenneise I,
Foster CS,
Larsen GR,
Lee NA,
and
Lee JJ.
Soluble P-selectin glycoprotein ligand 1 inhibits ocular inflammation in a murine model of allergy.
Invest Ophthalmol Vis Sci
40:
1336-1342,
1999[Abstract].
29.
Symon, FA,
Lawrence MB,
Williamson ML,
Walsh GM,
Watson SR,
and
Wardlaw AJ.
Functional and structural characterization of the eosinophil P-selectin ligand.
J Immunol
157:
1711-1719,
1996[Abstract].
30.
Symon, FA,
Walsh GM,
Watson SR,
and
Wardlaw AJ.
Eosinophil adhesion to nasal polyp endothelium is P-selectin-dependent.
J Exp Med
180:
371-376,
1994[Abstract].
31.
Ulfman, LH,
Kuijper PH,
van der Linden JA,
Lammers JW,
Zwaginga JJ,
and
Koenderman L.
Characterization of eosinophil adhesion to TNF-alpha-activated endothelium under flow conditions: alpha 4 integrins mediate initial attachment, and E-selectin mediates rolling.
J Immunol
163:
343-350,
1999
32.
Wardlaw, AJ,
Walsh GM,
and
Symon FA.
Adhesion interactions involved in eosinophil migration through vascular endothelium.
Ann NY Acad Sci
796:
124-137,
1996[Abstract].
33.
Weller, PF,
Rand TH,
Goelz SE,
Chi-Rosso G,
and
Lobb RR.
Human eosinophil adherence to vascular endothelium mediated by binding to vascular cell adhesion molecule 1 and endothelial leukocyte adhesion molecule 1.
Proc Natl Acad Sci USA
88:
7430-7433,
1991[Abstract].
34.
Wills-Karp, M.
Immunologic basis of antigen-induced airway hyperresponsiveness.
Annu Rev Immunol
17:
255-281,
1999[ISI][Medline].