bluuebunny/crossref_metadata_2025_split huggingface dataset:
Neuronal Fractalkine Expression in HIV-1 Encephalitis: Roles for Macrophage Recruitment and Neuroprotection in the Central Nervous System
Authors: Tong Ning , Perry Seth W. , Zhang Qing , James Harold J. , Guo Huang , Brooks Andrew , Bal Harshawardhan , Kinnear Sandra A. , Fine Steven , Epstein Leon G. , Dairaghi Daniel , Schall Thomas J. , Gendelman Howard E. , Dewhurst Stephen , Sharer Leroy R. , Gelbard Harris A. 
Published: April 2014

Abstract
HIV-1 infection of the brain results in chronic inflammation, contributing to the neuropathogenesis of HIV-1 associated neurologic disease. HIV-1-infected mononuclear phagocytes (MP) present in inflammatory infiltrates produce neurotoxins that mediate inflammation, dysfunction, and neuronal apoptosis. Neurologic disease is correlated with the relative number of MP in and around inflammatory infiltrates and not viral burden. It is unclear whether these cells also play a neuroprotective role. We show that the chemokine, fractalkine (FKN), is markedly up-regulated in neurons and neuropil in brain tissue from pediatric patients with HIV-1 encephalitis (HIVE) compared with those without HIVE, or that were HIV-1 seronegative. FKN receptors are expressed on both neurons and microglia in patients with HIVE. These receptors are localized to cytoplasmic structures which are characterized by a vesicular appearance in neurons which may be in cell-to-cell contact with MPs. FKN colocalizes with glutamate in these neurons. Similar findings are observed in brain tissue from an adult patient with HIVE. FKN is able to potently induce the migration of primary human monocytes across an endothelial cell/primary human fetal astrocyte trans-well bilayer, and is neuroprotective to cultured neurons when coadministered with either the HIV-1 neurotoxin platelet activating factor (PAF) or the regulatory HIV-1 gene product Tat. Thus focal inflammation in brain tissue with HIVE may up-regulate neuronal FKN levels, which in turn may be a neuroimmune modulator recruiting peripheral macrophages into the brain, and in a paracrine fashion protecting glutamatergic neurons.
Cell-Mediated DNA Transport Between Distant Inflammatory Sites Following Intradermal DNA Immunization in the Presence of Adjuvant
Authors: La Cava Antonio , Billetta Rosario , Gaietta Guido , Bonnin Dustan B. , Baird Stephen M. , Albani Salvatore 
Published: April 2014

AbstractAfter intradermal genetic immunization, naked DNA is transported from the site of injection to regional lymph nodes. Little is known on how inflammation influences this process and whether DNA is transported beyond local lymph nodes. In the experiments herein reported, we injected naked DNA in the presence of adjuvant to address questions related to 1) the fate of naked DNA in the presence of inflammation; 2) the generation of immune responses to the encoded protein during inflammation; and, more in general, 3) the fate of ingested molecules beyond regional lymph nodes during inflammation. Two sites of inflammation were induced in vivo in mice. Naked DNA was injected in the nape together with adjuvant, and adjuvant only was injected at a distant peritoneal site. Injected DNA, uptaken at the primary dermal site of inflammation, was transported beyond regional lymph nodes to distant organs such as the spleen and to the distant peritoneal site of inflammation. This transport, mediated by CD11b+ cells, was cumulative during chronic inflammation. These results indicate a novel route of transport of DNA beyond regional lymph nodes and may have specific implications for DNA-based immune modulation.
Effects of Liver-Derived Dendritic Cell Progenitors on Th1- and Th2-Like Cytokine Responses In Vitro and In Vivo
Authors: Khanna Ajai , Morelli Adrian E. , Zhong Cuiping , Takayama Takuya , Lu Lina , Thomson Angus W. 
Published: April 2014

AbstractThere is evidence that donor-derived dendritic cells (DC), particularly those at a precursor/immature stage, may play a role in the immune privilege of liver allografts. Underlying mechanisms are poorly understood. We have examined the influence of in vitro generated mouse liver-derived DC progenitors (DCp) on proliferative, cytotoxic, and Th1/Th2 cytokine responses induced in allogeneic T cells. Liver DCp, propagated in GM-CSF from C57B10 mice (H2b), induced only minimal proliferation, and weak cytotoxic responses in allogeneic (C3H; H2k) T cells compared with mature bone marrow (BM)-derived DC. Flow-cytometric analysis of intracellular cytokine staining revealed that mature BM DC, but not liver DCp, elicited CD4+ T cell production of IFN-γ. Intracellular expression of IL-10 was very low in both BM DC- and liver DCp-stimulated CD4+ T cells. Only stimulation by liver DCp was associated with IL-10 secretion in primary MLR. Notably, these liver DCp cocultured with allogeneic T cells stained strongly for IL-10. Following local (s.c.) injection in allogeneic recipients, both BM DC and liver DCp homed to T cell areas of draining lymph nodes and spleen, where they were readily detected by immunohistochemistry up to 2 wk postinjection. Liver DCp induced clusters of IL-10- and IL-4-secreting mononuclear cells, whereas Th2 cytokine-secreting cells were not detected in mice injected with mature BM DC. By contrast, comparatively high numbers of IFN-γ+ cells were induced by BM DC. Modulation of Th2 cytokine production by donor-derived DCp may contribute to the comparative immune privilege of hepatic allografts.
Functional Role of the Noncatalytic Subunit of Complement C5 Convertase
Authors: Rawal Nenoo , Pangburn Michael K. 
Published: April 2014

AbstractThe C5 convertase is a serine protease that consists of two subunits: a catalytic subunit which is bound in a Mg2+-dependent complex to a noncatalytic subunit. To understand the functional role of the noncatalytic subunit, we have determined the C5-cleaving properties of the cobra venom factor-dependent C5 convertase (CVF,Bb) made with CVF purified from the venom of Naja naja (CVFn) and Naja haje (CVFh) and compared them to those for two C3b-dependent C5 convertases (ZymC3b,Bb and C3b,Bb). A comparison of the kinetic parameters indicated that although the four C5 convertases (CVFn,Bb, ZymC3b,Bb, CVFh,Bb, and C3b,Bb) had similar catalytic rate constants (kcat = 0.004–0.012 s−1) they differed 700-fold in their affinity for the substrate as indicated by the Km values (CVFn,Bb = 0.036 μM, ZymC3b,Bb = 1.24 μM, CVFh,Bb = 14.0 μM, and C3b,Bb = 24 μM). Analysis of binding interactions between C5 and the noncatalytic subunits (CVFh or C3b, or CVFn) using the BIAcore, revealed dissociation binding constants (Kd) that were similar to the Km values of the respective enzymes. The kinetic and binding data demonstrate that the binding site for C5 resides in the noncatalytic subunit of the enzyme, the affinity for the substrate is solely determined by the noncatalytic subunit and the catalytic efficiency of the enzyme appears not to be influenced by the nature of this subunit.
Mamu-I: A Novel Primate MHC Class IB-Related Locus with Unusually Low Variability
Authors: Urvater Julie A. , Otting Nel , Loehrke Jamie H. , Rudersdorf Richard , Slukvin Igor I. , Piekarczyk Marian S. , Golos Thaddeus G. , Hughes Austin L. , Bontrop Ronald E. , Watkins David I. 
Published: April 2014

AbstractThe rhesus macaque is an important animal model for several human diseases and organ transplantation. Therefore, definition of the MHC of this species is crucial to the development of these models. Unfortunately, unlike humans, lymphocytes from a single rhesus macaque express up to 12 different MHC class I cDNAs. From which locus these various alleles are derived is unclear. In our attempts to define the MHC class I loci of the rhesus macaque, we have identified an unusual MHC class I locus, Mamu-I. We isolated 26 I locus alleles from three different macaque species but not from three other Cercopithecine genera, suggesting that the I locus is the result of a recent duplication of the B locus occurring after the divergence of macaques from the ancestor of the other extant Cercopithecine genera. Mamu-I mRNA transcripts were detected in all tissues examined and Mamu-I protein was produced in rhesus B lymphoblastoid cell lines. Furthermore, Mamu-I protein was detected by flow cytometry on the surface of human 721.221 cells transfected with Mamu-I. In contrast to the polymorphism present at this locus, there is unusually low sequence variability, with the mean number of nucleotide differences between alleles being only 3.6 nt. Therefore, Mamu-I is less variable than any other polymorphic MHC class I locus described to date. Additionally, no evidence for positive selection on the peptide binding region was observed. Together, these results suggest that Mamu-I is an MHC class I locus in primates that has features of both classical and nonclassical loci.
Mucosa-Specific Targets for Regulation of IFN-γ Expression: Lamina Propria T Cells Use Differentcis-Elements than Peripheral Blood T Cells to Regulate Transactivation of IFN-γ Expression
Authors: Gonsky Rivkah , Deem Richard L. , Bream Jay H. , Lee Doo Han , Young Howard A. , Targan Stephan R. 
Published: April 2014

AbstractActivation of lamina propria (LP) T cells via the CD2 pathway enhances IFN-γ (IFN-γ) secretion with further enhancement after CD28 coligation. The molecular mechanisms regulating IFN-γ expression in LP T cells remain unknown. Previous studies in PBL and T cell lines identified cis- and trans-regulatory elements in TCR-mediated expression of IFN-γ. This study examines CD2 and PMA/ionophore-responsive IFN-γ promoter elements. Activation of LPMC via CD2-induced IFN-γ secretion and a parallel up-regulation of mRNA expression. CD28 coligation enhanced mRNA stability without up-regulating transcription as measured by nuclear run-on. Transfection of a −2.7-kb IFN-γ promoter-reporter construct into PBL and LP mononuclear cells (LPMC) revealed significant promoter activity after CD2 activation, with additional transactivation after CD2/CD28 costimulation in PBL, but not in LPMC. Functional analysis using truncated promoter fragments identified distinct cis-regulatory regions selectively transactivating IFN-γ expression in PBL compared with LPMC. In PBL, CD2 activation elements reside within the −108- to +64-bp region. However, in LPMC the upstream region between −204 and −108 bp was essential. Transfection of the proximal and distal AP-1-binding elements, as well as TRE/AP-1 constructs, revealed functional activation of AP-1 subsequent to CD2 signaling, with activation critical in PBL but diminished in LPMC. Electromobility shift analysis using oligonucleotides encompassing the proximal, distal, and BED/AP-1-binding regions failed to demonstrate selective transactivation after CD2 signaling of LPMC. This report provides evidence that activation of LPMC results in transactivation of multiple promoter elements regulating IFN-γ expression distinct from those in PBL.
Structural Correlates of an Anticarcinoma Antibody: Identification of Specificity-Determining Residues (SDRs) and Development of a Minimally Immunogenic Antibody Variant by Retention of SDRs Only
Authors: Tamura Midori , Milenic Diane E. , Iwahashi Makoto , Padlan Eduardo , Schlom Jeffrey , Kashmiri S. V. S. 
Published: April 2014

Abstract
Clinical utility of murine mAbs is limited because many elicit Abs to murine Ig constant and variable regions in patients. An Ab humanized by the current procedure of grafting all the complementarity determining regions (CDRs) of a murine Ab onto the human Ab frameworks is likely to be less immunogenic, except that its murine CDRs could still evoke an anti-variable region response. Previous studies with anticarcinoma mAb CC49 showed that light chain LCDR1 and LCDR2 of humanized CC49 could be replaced with the corresponding CDRs of a human Ab with minimal loss of Ag-binding activity. The studies reported in this paper were undertaken to dissect the CC49 Ag-binding site to identify 1) specificity determining residues (SDRs), the residues of the hypervariable region that are most critical in Ag-Ab interaction, and 2) those residues that contribute to the idiotopes that are potential targets of patients’ immune responses. A panel of variants generated by genetic manipulation of the murine CC49 hypervariable regions were evaluated for their relative Ag-binding affinity and reactivity to sera from several patients who had been immunized with murine CC49. One variant, designated HuCC49V10, retained only the SDRs of CC49 and does not react with the anti-variable region Abs of the sera from the murine CC49-treated patients. These studies thus demonstrate that the genetic manipulation of Ab variable regions can be accomplished by grafting only the SDRs of a xenogeneic Ab onto human Ab frameworks. This approach may reduce the immunogenicity of Abs to a minimum.
Porcine Lung Surfactant Protein D: Complementary DNA Cloning, Chromosomal Localization, and Tissue Distribution
Authors: van Eijk Martin , Haagsman Henk P. , Skinner Thomas , Archibold Alan , Reid Kenneth B. M. , Lawson Peter R. 
Published: April 2014

Abstract
Porcine organs and lung surfactant have medically important applications in both xenotransplantation and therapy. We have started to characterize porcine lung surfactant by cloning the cDNA of porcine surfactant protein D (SP-D). SP-D and SP-A are important mediators in innate immune defense for the lung and possibly other mucosal surfaces. Porcine SP-D will also be an important reagent for use in existing porcine animal models for human lung infections. The complete cDNA sequence of porcine SP-D, including the 5′ and 3′ untranslated regions, was determined from two overlapping bacteriophage clones and by PCR cloning. Three unique features were revealed from the porcine sequence in comparison to SP-D from other previously characterized species, making porcine SP-D an intriguing species addition to the SP-D/collectin family. The collagen region contains an extra cysteine residue, which may have important structural consequences. The other two differences, a potential glycosylation site and an insertion of three amino acids, lie in the loop regions of the carbohydrate recognition domain, close to the carbohydrate binding region and thus may have functional implications. These variations were ruled out as polymorphisms or mutations by confirming the sequence at the genomic level in four different pig breeds. Porcine SP-D was shown to localize primarily to the lung and with less abundance to the duodenum, jejunum, and ileum. The genes for SP-D and SP-A were also shown to colocalize to a region of porcine chromosome 14 that is syntenic with the human and murine collectin loci.
Normal Isotype Switching in B Cells Lacking the Iμ Exon Splice Donor Site: Evidence for Multiple Iμ-Like Germline Transcripts
Authors: Kuzin Igor I. , Ugine Gregory D. , Wu Dongming , Young Fay , Chen Jianzhu , Bottaro Andrea 
Published: April 2014

Abstract
Ig class switch recombination (CSR) in activated B cells is preceded by the generation of “switch” transcripts from the heavy chain constant region (CH) genes targeted for rearrangement. Switch transcripts include a sterile “I” exon spliced onto the first CH exon. Targeted mutations disrupting the expression or splicing of I exons severely hamper CSR to all tested CH loci, except μ. However, all μ switch transcript mutations tested so far have left the Iμ exon splice donor site intact. To test the possibility that the residual CSR activity in Iμ mutants could be due to splicing of a truncated Iμ exon, we generated new mutants specifically lacking the Iμ splice donor site. Surprisingly, normal CSR was observed in the Iμ splice donor mutants even in the absence of detectable spliced Iμ transcripts. In a search for potential alternative sources of switch-like transcripts in the μ locus, we identified two novel exons which map just upstream of the Sμ region and splice onto the Cμ1 exon. Their expression is detectable from early B cell developmental stages, and, at least in hybridomas, it does not require the Eμ enhancer. These studies highlight a unique structure for the μ locus I exon region, with multiple nested switch transcript-like exons mapping upstream of Sμ. We propose that all of these transcripts directly contribute to μ class switching activity.
IL-13 Is a Susceptibility Factor forLeishmania majorInfection
Authors: Matthews David J. , Emson Claire L. , McKenzie Grahame J. , Jolin Helen E. , Blackwell Jenefer M. , McKenzie Andrew N. J. 
Published: April 2014

AbstractLeishmania major infection is useful as an experimental model to define factors responsible for the development and maintenance of Th cell immune responses. Studies using inbred mouse strains have identified that the Th1 response characteristic of C57BL/6 mice results in healing, whereas BALB/c mice fail to control the infection due to the generation of an inappropriate Th2 response. We now demonstrate that IL-13 is a key factor in determining susceptibility to L. major infection. Overexpression of IL-13 in transgenic mice makes the normally resistant C57BL/6 mouse strain susceptible to L. major infection even in the absence of IL-4 expression. This susceptibility correlates with a suppression of IL-12 and IFN-γ expression. Furthermore, using BALB/c mice deficient in the expression of IL-4, IL-13, or both IL-13 and IL-4, we demonstrate that IL-13-deficient mice are resistant to infection and that there is an additive effect of deleting both IL-4 and IL-13.
The Neuronal Apoptosis Inhibitory Protein (Naip) Is Expressed in Macrophages and Is Modulated After Phagocytosis and During Intracellular Infection withLegionella pneumophila
Authors: Diez Eduardo , Yaraghi Zahra , MacKenzie Alex , Gros Philippe 
Published: April 2014

AbstractLegionella pneumophila is an intracellular pathogen that causes Legionnaires’ disease in humans. Inbred mouse strains are uniformly resistant to L. pneumophila infection with the notable exception of A/J, where the chromosome 13 locus Lgn1 renders A/J macrophages permissive to L. pneumophila replication. The mouse Lgn1 region is syntenic with the spinal muscular atrophy (SMA) locus on human chromosome 5 and includes several copies of the neuronal apoptosis inhibitory protein (Naip) gene. We have analyzed a possible link among Lgn1, Naip, and macrophage function. RNA expression studies show that Naip (mostly copy 2) mRNA transcripts are expressed in macrophage-rich tissues, such as spleen, lung, and liver and are abundant in primary macrophages. Immunoblotting and immunoprecipitation analyses identify Naip protein expression in mouse macrophages and in macrophage cell lines RAW 264.7 and J774A. Interestingly, macrophages from permissive A/J mice express significantly less Naip protein than their nonpermissive C57BL/6J counterpart. Naip protein expression is increased after phagocytic events. Naip protein levels during infection with either virulent or avirulent strains of L. pneumophila increase during the first 6 h postinfection and remain elevated during the 48-h observation period. This enhanced expression is also observed in macrophages infected with Salmonella typhimurium. Likewise, an increase in Naip protein levels in macrophages is observed 24 h after phagocytosis of Latex beads. The cosegregation of Lgn1 and Naip together with the detected Naip protein expression in host macrophages as well as its modulation after phagocytic events and during intracellular infection make it an attractive candidate for the Lgn1 locus.
Inhibition of Mesangial Cell Nitric Oxide in MRL/lpr Mice by Prostaglandin J2 and Proliferator Activation Receptor-γ Agonists
Authors: Reilly Christopher M. , Oates James C. , Cook James A. , Morrow Jason D. , Halushka Perry V. , Gilkeson Gary S. 
Published: April 2014

Abstract
MRL/Mp-lpr/lpr (MRL/lpr) mice develop immune complex glomerulonephritis similar to human lupus. Glomerular mesangial cells are key modulators of the inflammatory response in lupus nephritis. When activated, these cells secrete inflammatory mediators including NO and products of cyclooxygenase perpetuating the local inflammatory response. PGJ2, a product of cyclooxygenase, is a potent in vitro inhibitor of macrophage inflammatory functions and is postulated to function as an in vivo inhibitor of macrophage-mediated inflammatory responses. We hypothesized that in lupus, a defect in PGJ2 production allows the inflammatory response to continue unchecked. To test this hypothesis, mesangial cells were isolated from MRL/lpr and BALB/c mice and stimulated with IL-1β or LPS plus IFN-γ. In contrast to the 2- to 3-fold increase in PGJ2 production by stimulated BALB/c mesangial cells, supernatant PGJ2 did not increase in MRL/lpr mesangial cell cultures. NO production in stimulated MRL/lpr and BALB/c mesangial cells, was blocked by PGJ2 and pioglitazone. These studies suggest that abnormalities in PGJ2 production are present in MRL/lpr mice and may be linked to the heightened activation state of mesangial cells in these mice.
C-Reactive Protein Binding to Murine Leukocytes Requires Fcγ Receptors
Authors: Stein Mary-Pat , Mold Carolyn , Du Clos Terry W. 
Published: April 2014

Abstract
Human C-reactive protein (CRP) is an acute phase protein that binds to receptors on human and mouse leukocytes. We have recently determined that the high and low affinity receptors for CRP on human leukocytes are FcγRIIa and FcγRI, respectively. Previous work by others suggested that CRP receptors on mouse macrophages are distinct from FcγR. We have taken advantage of the availability of mice deficient in one or more FcγR to reexamine the role of FcγR in CRP binding to mouse leukocytes. Three strains of FcγR-deficient mice were examined: γ-chain-deficient mice that lack FcγRI and FcγRIII, FcγRII-deficient mice, and mice deficient in both γ-chain and FcγRII that lack all FcγR. No binding of CRP was detected to leukocytes from double-deficient mice, indicating that FcγR are required for CRP binding. CRP binding to leukocytes from γ-chain-deficient and FcγRII-deficient mice was reduced compared with binding to leukocytes from wild-type mice. Further analysis of CRP binding to macrophages, neutrophils, and lymphocytes provides direct evidence that FcγRIIb1, FcγRIIb2, and FcγRI are the receptors for CRP on mouse leukocytes. These findings may have important implications in understanding the physiological function of CRP.