Structure-Immune Response Relationships of Hapten-Modified Collagen II Peptides in a T-Cell Model of Allergic Contact Dermatitis

Allergic contact dermatitis (ACD) is mediated by T cells that specifically recognize hapten-modified peptides. T cells are known to recognize antigens as short processed peptides bound to major histocompatibility complex (MHC) molecules on the surface of antigen-presenting cells (APC). It has previously been demonstrated that T cells can specifically recognize carbohydrates on the lysine at position 264 of the immunodominant (256−273) sequence from type II collagen (CII) and that such recognition is critical for the development of arthritis in mice and may play a role in rheumatoid arthritis in humans. In the present study, we have used this approach in modeling ACD, but instead of the carbohydrate, the strong sensitizer 2,4-dinitrofluorobenzene (DNFB) is bound to the ε-amine of the lysine at position 264. Specific T-cell hybridomas of this antigenic peptide, with dinitrophenyl (Dnp) on the ε-amine of lysine at position 264 (CIILysDnp 3), were established from mice immunized with CIILysDnp 3. In an immune response assay, these T-cell hybridomas were tested with a series of new synthetic hapten-modified peptides, all chemically identical except for the stereochemimistry (d,l) and the length of the position-264 amino acid side chain bonding the hapten. The T-cell hybridomas recognized the CIILysDnp 3 peptide used for immunization; interestingly, they also recognized the CII peptide with a one-carbon-longer side chain (homolysine), CIIhLysDnp 6, and CIIAlaPipDnp 11, having a ring structure analogous to that of lysine with the same number of carbons in the bonding chain as in the CIILysDnp 3 peptide used for immunization. Dnp-modified CII peptides with a shorter bonding chain produced no immune response. These data demonstrate that the T-cell recognition of the Dnp-modified peptides is highly specific and moreover dependent on the length of the amino acid side chain that bonds the Dnp

Two new species of Emersonella (Hymenoptera: Eulophidae: Entedoninae) from the Brazilian Atlantic Forest

Emersonella Girault, 1916 is a wasp genus including species that parasitize Chrysomelidae (Coleoptera) eggs, mainly Cassidinae. It occurs only in the Americas, and is primarily distributed in the Neotropical Region. In this paper two new species of Emersonella from the Atlantic Forest of southeastern Brazil are described and compared to similar species. Emersonella appendigastersp. nov. is characterized by an elongate last gastral tergite in female, thoracic dorsum flat, femora and tibiae yellowish in female, malar sulcus absent, frontal suture slightly down-curved laterally, eyes with scattered hairs, frons and vertex smooth, and propodeum smooth with small anteromedian foveae. Emersonella frieirocostaisp. nov. is characterized by an elongate gaster in the female, at most 1.3 times as long as mesosoma and pointed at apex, propodeum with two large anterolateral foveae, pronotum hardly visible in dorsal view, with posterior part smooth, transverse pronotal carina present and malar sulcus absent. Both species are egg parasitoids of Metriona elatior (Klug, 1820) (Chrysomelidae) which feeds on Solanum viarum Dunal (Solanaceae).</div

Locations sampled in Central Mexico.

<p>Locations sampled in Central Mexico with their geographical coordinates. Locations where sampled for bean species (<i>Phaseolus vulgaris</i>, <i>P</i>.<i>coccineus</i> and P. <i>lunatus</i>) and <i>Horismenus</i> parasitoid emergence. Table shows site code for each location, state, bean species present at each location (symp(vc) = sympatric populations of <i>P</i>. <i>vulgaris</i> and <i>P</i>. <i>coccineus</i>; symp(vl) = sympatric populations of <i>P</i>. <i>vulgaris</i> and <i>P</i>. <i>lunatus</i>; allop(c) = allopatric populations of <i>P</i>. <i>coccineus</i>; allop(v) = allopatric populations of <i>P</i>. <i>vulgaris</i> and allop (cult,v) = allopatric population of cultivated <i>P</i>. <i>vulgaris</i>), bean species from which parasitoids emerged, geographical coordinates (altitude, latitude and longitude) and parasitoid species emerging from the beans (B = <i>Horismenus butcheri</i> 1, 2 or 3; D = <i>H</i>. <i>depressus</i>2 and M = <i>H</i>. <i>missourensis</i> 2, or 3.</p

Tritrophic relationships.

<p><i>Phaseolus species</i>: Depicted at the top of the figure are three wild bean species sorted into categories based on the other beans found in their immediate environment. <i>Phaseolus lunatus</i> with a red background is found on the far left with its sympatric partner, <i>P</i>. <i>vulgaris</i> in green. To their right, <i>P</i>. <i>vulgaris</i> (again in green) is depicted alone as it is found at median altitudes to be in allopatry. This is followed by <i>P</i>. <i>vulgaris</i> (in green) and <i>P</i>. <i>coccineus</i> (in blue) found in sympatry and finally <i>P</i>. <i>coccineus</i> (in blue) alone to represent where it is found in allopatry. <i>Altitude range</i>: Directly beneath these is an altitude measure on the y-axis. The bars indicate the range of altitudes within which each of the above categories was collected. <i>Bruchine species</i>: Beneath this are the most common bruchine beetle speces that attack each one of the <i>Phaseolus</i> categories. <i>Horismenus profile</i>: Photos on the left identify the three species of described <i>Horismenus</i> wasp found emerging from bean seeds. Blue bars indicate emergence from the first field season (2006–7) and pink bars indicate emergence from the second field season (2007–8). Numbers below in gray are the number of emerging wasps from that category for that season. The pink and blue bars are the proportions of each wasp species to emerge from that category in each season and will all add to 1.</p

Phylogenetic markers and models of evolution.

<p>* one individual of <i>H</i>. <i>cyaenoviridis</i> has one long indel</p><p>Phylogenetic markers used in the current study and models of evolution applied in Bayesian analyses of the full (128 specimens) and reduced dataset (38 specimens).</p

A. Combined Bayesian half-compatible consensus tree of <i>Horismenus</i> based on mitochondrial and nuclear DNA regions.

<p>The species of parasitoid wasps defined by the Bayesian Poisson tree process coupled with the evolutionary placement algorithm and node supports are represented. Bayesian posterior probabilities and bootstrap support values are displayed below branches. Please see text and <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0136063#pone.0136063.t001" target="_blank">Table 1</a> for abbreviations. <b>B</b>. Barplot of the nucleotide diversities of each species. This analysis does not include information provided by the gaps and species that are not represented have a nucleotide diversity of zero.</p

Pediobius28S

Aligned 28S-D2 sequences in nexus format. Information on the samples given in the Excel readme file

PedioCO1

Aligned CO1 sequences in nexus format