GrassPlot v. 2.00 – first update on the database of multi-scale plant diversity in Palaearctic grasslands

Abstract: GrassPlot is a collaborative vegetation-plot database organised by the Eurasian Dry Grassland Group (EDGG) and listed in the Global Index of Vegetation-Plot Databases (GIVD ID EU-00-003). Following a previous Long Database Report (Dengler et al. 2018, Phyto- coenologia 48, 331–347), we provide here the first update on content and functionality of GrassPlot. The current version (GrassPlot v. 2.00) contains a total of 190,673 plots of different grain sizes across 28,171 independent plots, with 4,654 nested-plot series including at least four grain sizes. The database has improved its content as well as its functionality, including addition and harmonization of header data (land use, information on nestedness, structure and ecology) and preparation of species composition data. Currently, GrassPlot data are intensively used for broad-scale analyses of different aspects of alpha and beta diversity in grassland ecosystems

The Involvement of Immune Semaphorins in the Pathogenesis of Inflammatory Bowel Diseases (IBDs).

Immune semaphorins are a large family of proteins involved in the pathogenesis of inflammatory diseases through the regulation of immune homeostasis and tissue inflammation. We aim to assess the possible involvement of semaphorin3A (sema3A) and 4A (sema4A) in peripheral immune responses and bowel tissue inflammation of patients suffering from Crohn's disease (CD) and ulcerative colitis (UC).Twenty-seven CD patients and 10 UC patients were studied and compared to 10 patients followed for acute diverticulitis (disease control) and 12 healthy individuals. All were evaluated for sema3A expression on T regulatory cells (Tregs), serum levels of sema3A and sema4A, and tissue expression of sema3A and sema4A in bowel biopsies.The percentage (%) of T regulatory cells (Tregs) expressing sema3A in patients with active CD (64.5% ± 14.49%) and active UC (49.8% ± 16.45%) was significantly lower when compared to that of healthy controls (88.7% ± 3.6%, p< 0.001 and p< 0.0001, respectively). This expression was seen to be in negative correlation with CD activity. Serum levels of Sema4A were significantly lower in patients with CD and UC when compared to that of controls (5.69 ± 1 .48 ng\ml for CD, 5.26 ± 1.23 ng/ml for UC patients vs 9.74 ± 2.73 ng/ml for normal controls, P<0.001). Sema4A was highly expressed in lymphocytes of the lamina propria of CD and UC patients but absent in patients with diverticulitis or in normal individuals.Altered % of Tregs expressing sema3A in patients with inflammatory bowel diseases (IBD) is partially responsible for their failure in preventing CD4+ effector T cell induced inflammation in IBD in peripheral blood. The increased expression of sema4A in bowel biopsies from CD and UC patients is suggestive of its central role in regulating local tissue inflammation in the bowel

Clinical characteristics of Crohn’s disease patients.

<p>Clinical characteristics of Crohn’s disease patients.</p

Clinical correlation.

<p>The percentage of Treg cells expressing sema3A in peripheral blood of CD patients is found to be in negative correlation with the CDAI score (r = -0.46, p = 0.016).</p

The Involvement of Immune Semaphorins in the Pathogenesis of Inflammatory Bowel Diseases (IBDs) - Fig 1

<p>A: The percentage of Treg cells expressing sema3A. The percentage of Treg cells expressing sema3A in peripheral blood in patients suffering from Crohn’s disease [both active (n = 15) or in remission (n = 12)], ulcerative colitis (active, n = 10), and from patients suffering from acute diverticulitis (n = 10) compared to that from healthy controls (n = 12). Note the significantly altered percentage of Treg cells expressing sema3A in all IBD patients when compared to that of normal individuals. B: A representative figure of Treg cell expressing sema3A. A representative FACS analysis of Treg cell expressing sema3A in a CD patient compared to that of normal individual.</p

Sema3A staining in IBD.

<p>A representative biopsy from an active CD patient in which sema3A is intensely stained (+3) in the macrophages of the lamina propria (similarly in all studied groups). Black arrows denote positively stained macrophages.</p

Immunohistochemistry staining of sema4A.

<p>Sema4A is clearly detected in lymphocytes of the lamina propria in a biopsy taken from a CD patient (<b>A</b>), but was not detected in a biopsy taken from a diverticulitis patient (<b>B</b>) or from a normal individual. Black arrows denote positively stained lymphocytes.</p

Serum levels of sema4A.

<p>Serum levels of sema4A are significantly lower in CD (in active disease, n = 15) and UC patients (n = 10), when compared to the level of sema4A in normal individuals (n = 30).</p