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"Public health is a vital function that is in trouble." (1) This conclusion, reached in 1988 by the prestigious Institute of Medicine, still applies today. In fact, public health now […]

Background: WV Walks replicated the Wheeling Walks community-wide campaign methodology to promote physical activity. Methods: A social marketing intervention promoted walking among insufficiently active 40- to 65-year-olds throughout the television media market in north-central West Virginia. The intervention included participatory planning, an 8-week mass media-based campaign, and policy and environmental activities. Pre and post random-digit-dial cohort telephone surveys were conducted at baseline and immediately postcampaign in intervention and comparison regions. Results: The campaign resulted in maximal message awareness in north-central WV and demonstrated a significant increase in walking behavior represented by an absolute shift of 12% of the target population from insufficiently active to active (≥30 minutes, 5 days per week), versus the comparison community (adjusted odds ratio 1.82, CI: 1.05-3.17). Policy and environmental changes were also evident. Conclusions: This replication study increases our confidence that the initial effects observed in the Wheeling Walks intervention are generalizable to other similar rural communities. [ABSTRACT FROM AUTHOR]

We have generated a panel of potent, selective monoclonal antibodies that bind human and mouse αvβ6 integrin with high affinity (up to 15 pM). A subset of these antibodies blocked the binding of αvβ6 to the transforming growth factor-βl latency-associated peptide with IC50 values as low as 18 pM, and prevented the subsequent αvβ6-mediated activation of transforming growth factor-β1. The antibodies also inhibited αvβ6 binding to fibronectin. The blocking antibodies form two biochemical classes. One class, exemplified by the ligand-mimetic antibody 6.8G6, bound to the integrin in a divalent catlon-dependent manner, contained an RGD motif or a related sequence in CDR3 of the heavy chain, was blocked by RGD-containing peptides, and was internalized by αvβ6-expressing cells. Despite containing an RGD sequence, 6.8G6 was specific for αvβ6 and showed no cross-reactivity with the RGD-binding integrins αvβ3, αvβ8, or αIIbβ3. The nonligand-mimetic blocking antibodies, exemplified by 6.3G9, were cation-independent, were not blocked by RGD-containing peptides, were not internalized, and did not contain RGD or related sequences. These two classes of antibody were unable to bind simultaneously to αvβ6, suggesting that they may bind overlapping epitopes. The ’ligand-mimetic’ antibodies are the first to be described for αvβ6 and resemble those described for αIIbβ3. We also report for the first time the relative abilities of divalent cations to promote αvβ6 binding to latency-associated peptide and to the ligand-mimetic antibodies. These antibodies should provide valuable tools to study the ligand-receptor interactions of αvβ6 as well as the role of αvβ 6 in vivo. [ABSTRACT FROM AUTHOR]

The alpha(v)beta(6) integrin is up-regulated on epithelial malignancies and has been implicated in various aspects of cancer progression. Immunohistochemical analysis of alpha(v)beta(6) expression in 10 human tumor types showed increased expression relative to normal tissues. Squamous carcinomas of the cervix, skin, esophagus, and head and neck exhibited the highest frequency of expression, with positive immunostaining in 92% (n = 46), 84% (n = 49), 68% (n = 56), and 64% (n = 100) of cases, respectively. We studied the role of alpha(v)beta(6) in Detroit 562 human pharyngeal carcinoma cells in vitro and in vivo. Prominent alpha(v)beta(6) expression was detected on tumor xenografts at the tumor-stroma interface resembling the expression on human head and neck carcinomas. Nonetheless, coculturing cells in vitro with matrix proteins did not up-regulate alpha(v)beta(6) expression. Detroit 562 cells showed alpha(v)beta(6)-dependent adhesion and activation of transforming growth factor-beta (TGF-beta) that was inhibited >90% with an alpha(v)beta(6) blocking antibody, 6.3G9. Although both recombinant soluble TGF-beta receptor type-II (rsTGF-beta RII-Fc) and 6.3G9 inhibited TGF-beta-mediated Smad2/3 phosphorylation in vitro, there was no effect on proliferation. Conversely, in vivo, 6.3G9 and rsTGF-beta RII-Fc inhibited xenograft tumor growth by 50% (n = 10, P < 0.05) and >90% (n = 10, P < 0.001), respectively, suggesting a role for the microenvironment in this response. However, stromal collagen and smooth muscle actin content in xenograft sections were unchanged with treatments. Although further studies are required to consolidate in vitro and in vivo results and define the mechanisms of tumor inhibition by alpha(v)beta(6) antibodies, our findings support a role for alpha(v)beta(6) in human cancer and underscore the therapeutic potential of function blocking alpha(v)beta(6) antibodies.

Rationale: Transforming growth factor (TGF)-beta has a central role in driving many of the pathological processes that characterize pulmonary fibrosis. Inhibition of the integrin alpha(v)beta6, a key activator of TGF-beta in lung, is an attractive therapeutic strategy, as it may be possible to inhibit TGF-beta at sites of alpha(v)beta6 up-regulation without affecting other homeostatic roles of TGF-beta., Objectives: To analyze the expression of alpha(v)beta6 in human pulmonary fibrosis, and to functionally test the efficacy of therapeutic inhibition of alpha(v)beta6-mediated TGF-beta activation in murine bleomycin-induced pulmonary fibrosis., Methods: Lung biopsies from patients with a diagnosis of systemic sclerosis or idiopathic pulmonary fibrosis were stained for alpha(v)beta6 expression. A range of concentrations of a monoclonal antibody that blocks alpha(v)beta6-mediated TGF-beta activation was evaluated in murine bleomycin-induced lung fibrosis., Measurements and Main Results: Alpha(v)beta6 is overexpressed in human lung fibrosis within pneumocytes lining the alveolar ducts and alveoli. In the bleomycin model, alpha(v)beta6 antibody was effective in blocking pulmonary fibrosis. At high doses, there was increased expression of markers of inflammation and macrophage activation, consistent with the effects of TGF-beta inhibition in the lung. Low doses of antibody attenuated collagen expression without increasing alveolar inflammatory cell populations or macrophage activation markers., Conclusions: Partial inhibition of TGF-beta using alpha(v)beta6 integrin antibodies is effective in blocking murine pulmonary fibrosis without exacerbating inflammation. In addition, the elevated expression of alpha(v)beta6, an activator of the fibrogenic cytokine, TGF-beta, in human pulmonary fibrosis suggests that alpha(v)beta6 monoclonal antibodies could represent a promising new therapeutic strategy for treating pulmonary fibrosis.

The transforming growth factor (TGF)-beta-inducible integrin alpha v beta6 is preferentially expressed at sites of epithelial remodeling and has been shown to bind and activate latent precursor TGF-beta. Herein, we show that alpha v beta6 is overexpressed in human kidney epithelium in membranous glomerulonephritis, diabetes mellitus, IgA nephropathy, Goodpasture's syndrome, and Alport syndrome renal epithelium. To assess the potential regulatory role of alpha v beta6 in renal disease, we studied the effects of function-blocking alpha v beta6 monoclonal antibodies (mAbs) and genetic ablation of the beta6 subunit on kidney fibrosis in Col4A3-/- mice, a mouse model of Alport syndrome. Expression of alpha v beta6 in Alport mouse kidneys was observed primarily in cortical tubular epithelial cells and in correlation with the progression of fibrosis. Treatment with alpha v beta6-blocking mAbs inhibited accumulation of activated fibroblasts and deposition of interstitial collagen matrix. Similar inhibition of renal fibrosis was observed in beta6-deficient Alport mice. Transcript profiling of kidney tissues showed that alpha v beta6-blocking mAbs significantly inhibited disease-associated changes in expression of fibrotic and inflammatory mediators. Similar patterns of transcript modulation were produced with recombinant soluble TGF-beta RII treatment, suggesting shared regulatory functions of alpha v beta6 and TGF-beta. These findings demonstrate that alpha v beta6 can contribute to the regulation of renal fibrosis and suggest this integrin as a potential therapeutic target.

We have generated a panel of potent, selective monoclonal antibodies that bind human and mouse alpha(v)beta(6) integrin with high affinity (up to 15 pm). A subset of these antibodies blocked the binding of alpha(v)beta(6) to the transforming growth factor-beta1 latency-associated peptide with IC(50) values as low as 18 pm, and prevented the subsequent alpha(v)beta(6)-mediated activation of transforming growth factor-beta1. The antibodies also inhibited alpha(v)beta(6) binding to fibronectin. The blocking antibodies form two biochemical classes. One class, exemplified by the ligand-mimetic antibody 6.8G6, bound to the integrin in a divalent cation-dependent manner, contained an RGD motif or a related sequence in CDR3 of the heavy chain, was blocked by RGD-containing peptides, and was internalized by alpha(v)beta(6)-expressing cells. Despite containing an RGD sequence, 6.8G6 was specific for alpha(v)beta(6) and showed no cross-reactivity with the RGD-binding integrins alpha(v)beta(3), alpha(v)beta(8),or alpha(IIb)beta(3). The nonligand-mimetic blocking antibodies, exemplified by 6.3G9, were cation-independent, were not blocked by RGD-containing peptides, were not internalized, and did not contain RGD or related sequences. These two classes of antibody were unable to bind simultaneously to alpha(v)beta(6), suggesting that they may bind overlapping epitopes. The "ligand-mimetic" antibodies are the first to be described for alpha(v)beta(6) and resemble those described for alpha(IIb)beta(3). We also report for the first time the relative abilities of divalent cations to promote alpha(v)beta(6) binding to latency-associated peptide and to the ligand-mimetic antibodies. These antibodies should provide valuable tools to study the ligand-receptor interactions of alpha(v)beta(6) as well as the role of alpha(v)beta(6) in vivo.