Identification of a C3bi-specific membrane complement receptor that is expressed on lymphocytes, monocytes, neutrophils, and erythrocytes

Cells expressing a membrane C receptor (CR(3)) specific for C3b-inactivator- cleaved C3b (C3bi) were identified by rosette assay with C3bi-coated sheep erythrocytes (EC3bi) or C3bi-coated fluorescent microspheres (C3bi-ms). C3bi- ms, probably because of their smaller size, bound to a higher proportion of cells than did EC3bi. C3bi-ms bound to greater than 90 percent of mature neutrophils, 85 percent of monocytes, 92 percent of erythrocytes, and 12 percent of peripheral blood lymphocytes. Binding of C3bi-ms to neutrophils, monocytes, and erythrocytes was inhibited by fluid-phase C3bi, Fab anti-C3c, or Fab anti-C3d but was not inhibited by F(ab’)(2) anti-CR(1) (C3b receptor) or F(ab’)(2) anti-CR(2) (C3d receptor) nor by fluid-phase C3b, C3c, or C3d. This indicated that monocytes, neutrophils, and erythrocytes expressed C3bi receptors (CR(3)) that were separate and distinct from CR(1) and CR(2) and specific for a site in the C3 molecule that was only exposed subsequently to cleavage of C3b by C3b inactivator and that was either destroyed, covered, or liberated by cleavage of C3bi into C3c and C3d fragments. Lymphocytes differed from these other cell types in that they expressed CR2 in addition to CRa. Lymphocyte C3bi-ms rosettes were inhibited from 50 to 84 percent by F(ab’)(2)-anti-CR(2) or fluid-phase C3d, whereas C3d-ms rosettes were inhibited completely by F(ab’)(2) anti-CR(2), fluid-phase C3bi, or fluid- phase C3d. Thus, with lymphocytes, C3bi was bound to CR(3), and in addition was bound to CR(2) by way of the intact d region of the C3bi molecule. In studies of the acquisition of C receptors occurring during myeloid cell maturation, the ability to rosette with C3bi-coated particles was detected readily with immature low-density cells, whereas this ability was nearly undetectable with high density mature polymorphonuclear cells. This absence of C3bi binding to polymorphs was not due to a loss of the CR(3) but instead was due to the maturation-linked acquisition of the abiity to secrete elastase that cleaved reagent particle-bound C3bi into CR(3)-unreactive C3d. Neither neutrophils nor monocytes bound C3d-coated particles at any stage of maturation. Assay of CR(3) with mature neutrophils required inhibition of neutrophil elastase with either soybean trypsin inhibitor or anti-elastase antibodies, and the amounts of these elastase inhibitors required to allow EC3bi rosette formation increased with neutrophil maturation. Because lymphocytes bound C3bi to CR(2) as well as to CR(3), specific assay of lymphocyte CR(3) required saturation of membrane CR(2) with Fab’ anti-CR(2) before assay for rosettes with C3bi-ms. Only 3.5 percent of anti-CR(2)- treated peripheral blood lymphocytes bound C3bi-ms. Therefore, among normal blood lymphocytes the majority of the 12 percent C3bi-ms-binding cells expressed only CR(2) (8.5 percent), and the small proportion of C3bi-ms- binding cells that expressed CR(3) (3.5 percent) represented a distinct subset from the CR2(+) cells. Double-label assay indicated that 3.0 percent out of 3.5 percent of these CR(3)-bearing lymphocytes were B cells because they expressed membrane immunoglobulins. Of the remaining CR(3)(+) cells, 0.2 percent expressed either Leu-1 or 3A1 T cell antigens, and 0.6 percent expressed the OKM-1 monocyte-null lymphocyte determinant

Characterization of the lymphocyte membrane receptor for factor H (β1H- globulin) with an antibody to anti-factor H idiotype

Antibody to the binding site (idiotype) of anti-factor H was shown to have specificity for both B lymphocyte membrane H receptors and C3b. Goat F(ab’)(2) anti-human H was purified by absorption and elution from H agarose and used for rabbit immunization to produce anti-anti-H (aaH). After absorption with nonimmune goat IgG, (125)I-labeled aaH bound to B lymphocytes and to sheep erythrocytes coated with C3b (EC3b) but did not bind to T lymphocytes or to EC3d. All B cell- and C3b-specific activities of the aaH were removed and subsequently recovered by absorption and elution of the antibody from either C3-agarose or goat-anti-H-agarose. This indicated that the aaH probably recognized a single common antigenic structure that was shared by anti-H, C3b, and the membranes of B cells. Affinity-purified aaH resembled H in that it bound to B cells, blocked the uptake of H onto B cell H receptors, and triggered B cells to release endogenous factor I (C3b inactivator). In addition, aaH functioned with factor I as either a cofactor for cleavage of fluid-phase C3b or a potentiator for cleavage of bound C3b. This same spectrum of C3 binding functions could not be demonstrated with either sheep anti-C3b or rabbit-anti-C3c. Analysis by sodium dodecyl sulfate- polyacrylamide get electrophoresis of the [(3)H]leucine intrinsically labeled B cell proteins reactive with the purified aaH revealed proteins of 100,000 M(r) and 50,000 M(r) without reduction, and after complete reduction of disulfide bonds, a single protein band of 50,000 M(r). This same protein molecular weight profile was also demonstrated with labeled B cell proteins that were absorbed and eluted from H-agarose. Thus, aaH is apparently specific for both B cell H receptors and C3b. However, because parallel analysis of C3b confirmed its known 115,000- and 75,000-M(r) polypeptide chain structure, the H receptor is probably not C3b and shares only the structure of the H binding site with C3b

Membrane receptors of mouse leukocytes. II. Sequential expression of membrane receptors and phagocytic capacity during leukocyte differentiation

Analysis of four mature cell markers on mouse bone marrow leukocytes grown in vitro, demonstrated a distinct sequence of marker appearance during the terminal phases of granulocytic cell differentiation. A similar pattern of marker expression was also suggested by analysis of mature neutrophils and macrophages isolated from normal tissues. Among cultured neutrophils, receptors for the Fc portion of IgG (FcR) were first expressed on myelocytes and metamyelocytes, and then subsequently on more mature cells. Morphologically mature colony neutrophils (polymorphs) from agar cultures contained only FcR and complement receptor type two (CR(2)) (C3d receptor), and lacked both complement receptor type one (CR(1)) (C3b receptor) and the capacity to ingest latex, bacteria, or iron particles. Neutrophils from 2 and 3 wk liquid media cultures of marrow cells differed from agar grown neutrophils in that they had phagocytic capacity (particle ingestion) [Pi] in addition to FcR and CR(2). Furthermore, in the 4th and 5th wk of these continuous liquid cultures, CR(1) was also expressed, completing the surface marker profile of normal blood neutrophils. Based on these studies, the following order of appearance of these four markers on cells from the myelocytic series was proposed: FcR {arrow} FcR CR(2) {arrow} FcR CR(2) Pi {arrow} FcR CR(2) Pi CR(1). Differential studies of tissue leukocytes containing these same markers revealed that a heterogeneity existed among morphologically mature neutrophils. Even though 95 percent of blood polymorphs contained all four markers, the same was true of only half of spleen polymorphs and only 20 percent of bone marrow polymorphs. Cells of the monocyte-macrophage series were studies in parallel with neutrophils. Cultured marrow monocytes acquired the four mature cell markers so rapidly that the order of receptor appearance could not be determined. However, it was found that CR2 was lost during the terminal phase of monocyte maturation into activated macrophages

Cucumispora ornata n. sp. (Fungi: Microsporidia) infecting invasive 1 ‘demon shrimp’

Dikerogammarus haemobaphes, the ‘demon shrimp’, is an amphipod native to the Ponto-Caspian region. This species invaded the UK in 2012 and has become widely established. Dikerogammarus haemobaphes has the potential to introduce non-native pathogens into the UK, creating a potential threat to native fauna. This study describes a novel species of microsporidian parasite infecting 72.8% of invasive D. haemobaphes located in the River Trent, UK. The microsporidium infection was systemic throughout the host; mainly targeting the sarcolemma of muscle tissues. Electron microscopy revealed this parasite to be diplokaryotic and have 7-9 turns of the polar filament. The microsporidium is placed into the ‘Cucumispora’ genus based on host histopathology, fine detail parasite ultrastructure, a highly similar life-cycle and SSU rDNA sequence phylogeny. Using this data this novel microsporidian species is named Cucumispora ornata, where ‘ornata’ refers to the external beading present on the mature spore stage of this organism. Alongside a taxonomic discussion, the presence of a novel Cucumispora sp. in the United Kingdom is discussed and related to the potential control of invasive Dikerogammarus spp. in the UK and the health of native species which may come into contact with this parasite

New Kadampa Buddhists and Jungian psychological type

Building on previous studies on Canadian Anglicans and Catholics, this study examines and discusses the psychological type profile of 31 adherents to New Kadampa Buddhism. Like Anglicans and Catholics, Buddhists preferred introversion (I). Like Anglicans who preferred intuition (N) and unlike Catholics who preferred sensing (S), Buddhists displayed a preference for intuition (N). Unlike Anglicans and Catholics who both preferred feeling (F), Buddhists displayed a balance between feeling (F) and thinking (T). Like Anglicans and unlike Catholics, Buddhists preferred the Apollonian temperament (NF) over the Epimethean temperament (SJ). These data are discussed to interpret the psychological appeal of New Kadampa Buddhism

The first clawed lobster virus Homarus gammarus nudivirus (HgNV n. sp.) expands the diversity of the Nudiviridae

This is the final version. Available from Nature Research via the DOI in this record. Viral diseases of crustaceans are increasingly recognised as challenges to shellfish farms and fisheries. Here we describe the first naturally-occurring virus reported in any clawed lobster species. Hypertrophied nuclei with emarginated chromatin, characteristic histopathological lesions of DNA virus infection, were observed within the hepatopancreatic epithelial cells of juvenile European lobsters (Homarus gammarus). Transmission electron microscopy revealed infection with a bacilliform virus containing a rod shaped nucleocapsid enveloped in an elliptical membrane. Assembly of PCR-free shotgun metagenomic sequencing produced a circular genome of 107,063 bp containing 97 open reading frames, the majority of which share sequence similarity with a virus infecting the black tiger shrimp: Penaeus monodon nudivirus (PmNV). Multiple phylogenetic analyses confirm the new virus to be a novel member of the Nudiviridae: Homarus gammarus nudivirus (HgNV). Evidence of occlusion body formation, characteristic of PmNV and its closest relatives, was not observed, questioning the horizontal transmission strategy of HgNV outside of the host. We discuss the potential impacts of HgNV on juvenile lobster growth and mortality and present HgNV-specific primers to serve as a diagnostic tool for monitoring the virus in wild and farmed lobster stocks.Centre for Environment, Fisheries and Aquaculture Science (CEFAS)Innovate UKBBSR

Fitting Neutrino Physics with a U(1)_R Lepton Number

We study neutrino physics in the context of a supersymmetric model where a continuous R-symmetry is identified with the total Lepton Number and one sneutrino can thus play the role of the down type Higgs. We show that R-breaking effects communicated to the visible sector by Anomaly Mediation can reproduce neutrino masses and mixing solely via radiative contributions, without requiring any additional degree of freedom. In particular, a relatively large reactor angle (as recently observed by the Daya Bay collaboration) can be accommodated in ample regions of the parameter space. On the contrary, if the R-breaking is communicated to the visible sector by gravitational effects at the Planck scale, additional particles are necessary to accommodate neutrino data.Comment: 19 pages, 3 figures; v2: references added, constraints updated, overall conclusions unchange

The nonlinear anomalous lattice elasticity associated with the high-pressure phase transition in spodumene: A high precission static compression study

The high-pressure behavior of the lattice elasticity of spodumene, LiAlSi2O6, was studied by static compression in a diamond-anvil cell up to 9.3 GPa. Investigations by means of single-crystal XRD and Raman spectroscopy within the hydrostatic limits of the pressure medium focus on the pressure ranges around similar to 3.2 and similar to 7.7 GPa, which have been reported previously to comprise two independent structural phase transitions. While our measurements confirm the well-established first-order C2/c-P2(1)/c transformation at 3.19 GPa (with 1.2% volume discontinuity and a hysteresis between 0.02 and 0.06 GPa), both unit-cell dimensions and the spectral changes observed in high-pressure Raman spectra give no evidence for structural changes related to a second phase transition. Monoclinic lattice parameters and unit-cell volumes at in total 59 different pressure points have been used to re-calculate the lattice-related properties of spontaneous strain, volume strain, and the bulk moduli as a function of pressure across the transition. A modified Landau free energy expansion in terms of a one component order parameter has been developed and tested against these experimentally determined data. The Landau solution provides a much better reproduction of the observed anomalies than any equation-of-state fit to data sets truncated below and above P (tr), thus giving Landau parameters of K (0) = 138.3(2) GPa, K' = 7.46(5), lambda (V) = 33.6(2) GPa, a = 0.486(3), b = -29.4(6) GPa and c = 551(11) GPa