Utility of gastric biopsy in diagnosing IgG4‐related gastrointestinal disease

The utility of gastric biopsy for diagnosing immunoglobulin (Ig)G4‐related gastrointestinal disease (IgG4‐GID) remains unclear. Bottom‐heavy plasmacytosis (BHP) is a distinct feature of IgG4‐GID. To clarify the feasibility of using gastric biopsies to diagnose BHP in IgG4‐GID, we analyzed the histological features and immunostaining of gastric biopsy specimens from 31 known IgG4‐related disease (IgG4‐RD) patients and we assessed the presence of BHP in 1696 consecutive routine gastric biopsies. Cases with both >10 IgG4‐positive plasma cells per high‐power field and an IgG4/IgG‐positive ratio >40% were defined as IgG4‐high. Ten of the 31 IgG4‐RD patients were concluded to have IgG4‐GID, in which IgG4‐positive plasma cells were notably detected at the deeper part of the mucosa. Six cases displayed BHP whereas the remaining four cases showed transmural infiltration with concomitant Helicobacter pylori‐associated gastritis. In addition to BHP, we identified two unique histologic features for IgG4‐GID: plasmacytic aggregation in the muscularis mucosae and permeative plasmacytic infiltration between fundic glands in the non‐atrophic mucosa. Six of the routine cases (0.35%) displayed BHP, including a case with IgG4‐RD. IgG4‐GID can be suspected by the presence of gastric biopsy specimens with characteristic histological features. Such cases are recommended to undergo further examinations to determine whether IgG4‐RD is present

The Heterochromatin Block That Functions as a Rod Cell Microlens in Owl Monkeys Formed within a 15-Myr Time Span

In rod cells of many nocturnal mammals, heterochromatin localizes to the central region of the nucleus and serves as a lens to send light efficiently to the photoreceptor region. The genus Aotus (owl monkeys) is commonly considered to have undergone a shift from diurnal to nocturnal lifestyle. We recently demonstrated that rod cells of the Aotus species Aotus azarae possess a heterochromatin block at the center of its nucleus. The purpose of the present study was to estimate the time span in which the formation of the heterochromatin block took place. We performed three-dimensional hybridization analysis of the rod cell of another species, Aotus lemurinus. This analysis revealed the presence of a heterochromatin block that consisted of the same DNA components as those in A. azarae. These results indicate that the formation was complete at or before the separation of the two species. Based on the commonly accepted evolutionary history of New World monkeys and specifically of owl monkeys, the time span for the entire formation process was estimated to be 15 Myr at most

Pretaporter, a Drosophila protein serving as a ligand for Draper in the phagocytosis of apoptotic cells

金沢大学医薬保健研究域薬学系Phagocytic removal of cells undergoing apoptosis is necessary for animal development and tissue homeostasis. Draper, a homologue of the Caenorhabditis elegans phagocytosis receptor CED-1, is responsible for the phagocytosis of apoptotic cells in Drosophila, but its ligand presumably present on apoptotic cells remains unknown. An endoplasmic reticulum protein that binds to the extracellular region of Draper was isolated. Loss of this protein, which we name Pretaporter, led to a reduced level of apoptotic cell clearance in embryos, and the overexpression of pretaporter in the mutant flies rescued this defect. Results from genetic analyses suggested that Pretaporter functionally interacts with Draper and the corresponding signal mediators. Pretaporter was exposed at the cell surface after the induction of apoptosis, and cells artificially expressing Pretaporter at their surface became susceptible to Draper-mediated phagocytosis. Finally, the incubation with Pretaporter augmented the tyrosine-phosphorylation of Draper in phagocytic cells. These results collectively suggest that Pretaporter relocates from the endoplasmic reticulum to the cell surface during apoptosis to serve as a ligand for Draper in the phagocytosis of apoptotic cells. © 2009 European Molecular Biology Organization

Phylogenetic relationships of three species within the family Heligmonellidae (Nematoda; Heligmosomoidea) from Japanese rodents and a lagomorph based on the sequences of ribosomal DNA internal transcribed spacers, ITS-1 and ITS-2

Nematodes of the family Heligmonellidae (Heligmosomoidea; Trichostrongylina) reside in the digestive tracts of rodents and lagomorphs. Although this family contains large numbers of genera and species, genetic information on the Heligmonellidae is very limited. We collected and isolated adult worms of three species in Japan that belong to the family Heligmonellidae, namely Heligmonoides speciosus (Konno, 1963) Durette-Desset, 1970 (Hs) from Apodemus argenteus, Orientostrongylus ezoensis Tada, 1975 (Oe) from Rattus norvegicus and Lagostrongylus leporis (Schulz, 1931) (Ll) from Pentalagus furnessi, and sequenced the entire internal transcribed spacer regions, ITS-1 and ITS-2 of ribosomal DNA. ITS-1 of Hs, Oe and Ll was 426, 468 and 449 bp in length, and had a G＋C content of about 41, 41 and 37 %, respectively. ITS-2 of Hs, Oe and Ll was 297, 319 and 276 bp in length and had a G＋C content of about 38, 40 and 28%, respectively. The data of Hs, Oe and Ll were compared with those of two other known species within the family Heligmonellidae, Calorinensis minutus (Dujardin, 1845) (Cm) and Nippostrogylus brasiliensis (Travassos, 1914) (Nb), and with those of two species of Heligmosomidae (Heligmosomoidea), Heligmosomoides polygyrus bakeri and Ohbayashinema erbaevae. Phylogenetic analysis placed Hs, Oe and Ll in the same clade with Cm and Nb, forming a Heligmonellidae branch in both ITS-1 and ITS-2, separate from the Heligmosomoidea branch. These results demonstrated that the ITS-1 and ITS-2 sequences are useful for differentiating the Heligmonellidae nematode species. This study is the first to describe the ITS-1 and ITS-2 sequences of Hs, Oe and Ll