bluuebunny/crossref_metadata_2025_split huggingface dataset:
Differential signaling via surface IgM is associated with VH gene mutational status and CD38 expression in chronic lymphocytic leukemia
Authors: Lanham Stuart , Hamblin Terry , Oscier David , Ibbotson Rachel , Stevenson Freda , Packham Graham 
Published: January 2003

Abstract
The mutational status of tumor immunoglobulin VHgenes is providing a powerful prognostic marker for chronic lymphocytic leukemia (CLL), with patients having tumors expressing unmutated VH genes being in a less favorable subset. However, the biologic differences correlating with VH gene status that could determine the clinical course of the disease are unknown. Here we show that differing responses to IgM ligation are closely associated with VH gene status. Specifically, 80% of cases with unmutated VH genes showed increased global tyrosine phosphorylation following IgM ligation, whereas only 20% of samples with mutated VH genes responded (P = .0002). There was also an association between response to IgM ligation and expression of CD38 (P = .015). The Syk kinase, critical for transducing B-cell receptor (BCR)– derived signals, was constitutively present in all CLL samples, and there was a perfect association between global phosphorylation and induction of phosphorylation/activation of Syk. Nonresponsiveness to anti-IgM could be circumvented by ligation of IgD (10 of 15 samples tested) or the BCR-associated molecule CD79α (12 of 15 samples tested). These results suggest that multiple mechanisms underlie nonresponsiveness to anti-IgM in CLL and that retained responsiveness to anti-IgM contributes to the poor prognosis associated with the unmutated subset of CLL. The prognostic power of the in vitro response to IgM ligation remains to be determined in a large series, but the simple technology involved may present an alternative or additional test for predicting clinical course.
V(D)J recombinatorial repertoire diversification during intraclonal pro-B to B-cell differentiation
Authors: Wang Yui-Hsi , Zhang Zhixin , Burrows Peter D. , Kubagawa Hiromi , Bridges S. Louis , Findley Harry W. , Cooper Max D. 
Published: January 2003

AbstractThe initial B-cell repertoire is generated by combinatorial immunoglobulin V(D)J gene segment rearrangements that occur in a preferential sequence. Because cellular proliferation occurs during the course of these rearrangement events, it has been proposed that intraclonal diversification occurs during this phase of B-cell development. An opportunity to examine this hypothesis directly was provided by the identification of a human acute lymphoblastic leukemic cell line that undergoes spontaneous differentiation from pro-B cell to the pre-B and B-cell stages with concomitant changes in the gene expression profile that normally occur during B-cell differentiation. After confirming the clonality of the progressively differentiating cells, an analysis of immunoglobulin genes and transcripts indicated that pro-B cell members marked by the same DJ rearrangement generated daughter B cells with multiple VH and VL gene segment rearrangements. These findings validate the principle of intraclonal V(D)J diversification during B-cell generation and define a manipulable model of human B-cell differentiation.
IκB kinase 2 but not NF-κB–inducing kinase is essential for effective DC antigen presentation in the allogeneic mixed lymphocyte reaction
Authors: Andreakos Evangelos , Smith Clive , Monaco Claudia , Brennan Fionula M. , Foxwell Brian M. , Feldmann Marc 
Published: January 2003

AbstractAlthough dendritic cells (DCs) are the most potent antigen-presenting cells involved in numerous physiologic and pathologic processes, little is known about the signaling pathways that regulate DC activation and antigen-presenting function. Recently, we demonstrated that nuclear factor (NF)-κB activation is central to that process, as overexpression of IκBα blocks the allogeneic mixed lymphocyte reaction (MLR), an in vitro model of T-cell activation. In this study, we investigated the role of 2 putative NF-κB–inducing components, NF-κB–inducing kinase (NIK), and IκB kinase 2 (IKK2). Using an adenoviral gene transfer method to efficiently express dominant-negative (dn) forms of these molecules in monocyte-derived DCs, we found that IKK2dn but not NIKdn inhibited the allogeneic MLR. When DCs were fixed, this inhibitory effect of IKK2dn was lost, suggesting that IKK2 is involved in T-cell–derived signals that enhance DC antigen presentation during the allogeneic MLR period and does not have an effect on viability or differentiation state of DCs prior to coculture with T cells. One such signal is likely to be CD40 ligand (CD40L), as IKK2dn blocked CD40L but not lipopolysaccharide (LPS)–induced NF-κB activation, cytokine production, and up-regulation of costimulatory molecules and HLA-DR in DCs. In summary, our results demonstrate that IKK2 is essential for DC activation induced by CD40L or contact with allogeneic T cells, but not by LPS, whereas NIK is not required for any of these signals. In addition, our results support IKK2 as a potential therapeutic target for the down-regulation of unwanted immune responses that may occur during transplantation or autoimmunity.
Distinguishable live erythroid and myeloid cells in β-globin ECFP x lysozyme EGFP mice
Authors: Heck Susanne , Ermakova Olga , Iwasaki Hiromi , Akashi Koichi , Sun Chiao-Wang , Ryan Thomas M. , Townes Tim , Graf Thomas 
Published: January 2003

AbstractWe previously described a mouse line that contains green myelomonocytic cells due to the knock-in of enhanced green fluorescence protein (EGFP) into the lysozyme M gene.1 We have now created a transgenic line with fluorescent erythroid cells using a β-globin locus control region driving the enhanced cyan fluorescence protein (ECFP) gene. These mice exhibit cyan fluorescent cells specifically in the erythroid compartment and in megakaryocyte-erythroid progenitors. Crossing the animals with lysozyme EGFP mice yielded a line in which live erythroid and myeloid cells can readily be distinguished by fluorescence microscopy and by fluorescence-activated cell-sorter scanner. This cross allowed unambiguous identification of unstained mixed erythroid-myeloid colonies for the first time. The new mouse lines should become useful tools to dissect the branching between erythroid and myelomonocytic cells during in vitro differentiation of definitive multipotent progenitors.
LSSIG is a novel murine leukocyte-specific GPCR that is induced by the activation of STAT3
Authors: Senga Takeshi , Iwamoto Shotaro , Yoshida Tsunehiko , Yokota Takashi , Adachi Koichi , Azuma Eiichi , Hamaguchi Michinari , Iwamoto Takashi 
Published: January 2003

AbstractG-protein–coupled receptors (GPCRs) transduce the signal of a wide variety of chemokines, cytokines, neurotransmitters, hormones, odorants, and others to regulate the biologic homeostasis, including hematopoiesis and immunity. Here we report the molecular cloning of leukocyte-specific STAT-induced GPCR (LSSIG), which is a novel murine orphan GPCR with the highest homology to human GPR43. The mRNA expression of LSSIG was clearly induced in M1 leukemia cells during the leukemia inhibitory factor (LIF)–induced differentiation to macrophages, and the induction was evidently signal transducers and activators of transcription 3 (STAT3)–dependent. GPR43 expression was also strongly induced in HL-60 and U937 leukemia cells during the differentiation to monocytes. Further analysis showed that the expression of both LSSIG and GPR43 is highly restricted in hematopoietic tissues. Cytokine-stimulation induced LSSIG and GPR43 in bone marrow cells, and monocytes and neutrophils, respectively. These results suggest that LSSIG and GPR43 might play pivotal roles in differentiation and immune response of monocytes and granulocytes.
Gene expression and immunologic consequence of SPAN-Xb in myeloma and other hematologic malignancies
Authors: Wang Zhiqing , Zhang Yana , Liu Haichao , Salati Emanuela , Chiriva-Internati Maurizio , Lim Seah H. 
Published: January 2003

Abstract
Recent studies in tumor immunology indicate that malignant cells frequently express normal testicular-specific proteins. Because these proteins show restricted normal tissue distribution, they are usually highly immunogenic and may be potential targets for immunotherapy. In the present study, we have used a pair of sequence-specific primers in reverse transcription–polymerase chain reaction (RT-PCR) and sequence analysis to demonstrate that the X-linked gene encoding SPAN-Xb is expressed in multiple myeloma and other hematologic malignancies such as chronic lymphocytic leukemia (CLL), chronic myeloid leukemia (CML), and acute myeloid leukemia (AML). RT-PCR analysis demonstrates that SPAN-Xb is a cancer/testis antigen and shows a restricted normal tissue expression. It is not expressed in any normal tissue except testis. SPAN-Xb recombinant protein was produced and used in enzyme-linked immunosorbent assay (ELISA) and Western blot analysis. High-titer immunoglobulin G (IgG) antibodies, of IgG3 or IgG2 subclass, against SPAN-Xb were detectable in the sera of these patients. In contrast, SPAN-Xb mRNA or antibodies could not be detected in any of the healthy donors. There was a good correlation betweenSPAN-Xb gene expression and B-cell immune responses. These results suggest the in vivo immunogenicity of the SPAN-Xb protein. The presence of high-titer IgG responses suggests that the B-cell responses are likely to have been generated with CD4 T-cell cognitive help. Based on these data, we conclude that SPAN-Xb is a novel member of the family of cancer/testis antigens aberrantly expressed by, and capable of inducing, immune responses in patients with multiple myeloma and other hematologic malignancies.
IL-15 enhances survival and function of HIV-specific CD8+ T cells
Authors: Mueller Yvonne M. , Bojczuk Paul M. , Halstead E. Scott , Kim Alfred H. J. , Witek James , Altman John D. , Katsikis Peter D. 
Published: January 2003

AbstractHIV-specific CD8+ T cells are prone to undergo apoptosis, and this may affect their ability to control HIV infection. Because CD8-mediated immune responses play a key role in controlling HIV infection, enhancing the survival and effector function of HIV-specific CD8+ T cells may augment their ability to control HIV virus. We show here that interleukin 15 (IL-15) potently inhibits spontaneous and CD95/Fas-induced apoptosis of HIV-specific CD8+ T cells. IL-15 inhibits apoptosis in both CD45RA−CD62L− and CD45RA+CD62L− effector memory subpopulations of these cells. Furthermore, IL-15 greatly enhances the survival of HIV-specific CD8+ T cells in long-term cultures. Finally, IL-15 directly enhances activation, interferon γ (IFNγ) production, and direct ex vivo cytotoxicity of HIV-specific CD8+ T cells. Thus, IL-15 potently enhances the survival and effector function of HIV-specific CD8+ T cells and, therefore, may prove useful in augmenting the antiviral function of these cells.
A CD45 minigene restores regulated isoform expression and immune function in CD45-deficient mice: therapeutic implications for human CD45-null severe combined immunodeficiency
Authors: Virts Elizabeth L. , Diago Oscar , Raschke William C. 
Published: January 2003

AbstractTransgenic mice have been generated that carry a CD45 minigene under control of the human leukocyte function-associated antigen (LFA-1, CD11a) promoter. CD45-null mice carrying the transgene exhibit the lymphocyte lineage-specific isoform expression patterns of wild-type mice. Furthermore, these mice have normal thymocyte development and peripheral T-cell numbers. The proliferative ability of T cells in response to mitogens and antigen also is regained, as is B-cell responsiveness to anti-IgM. The antibody response to antigen is also restored and is similar to that of normal mice. Therefore, introduction of a functional CD45 minigene is sufficient to overcome the principal severe combined immunodeficiency (SCID)–associated defects and represents a potential route to a gene therapy for human CD45-deficent SCID.
Efficacy of 2-chlorodeoxyadenosine in refractory factor VIII inhibitors in persons without hemophilia
Authors: Sallah Sabah , Wan Jim Y. 
Published: January 2003

Abstract
The authors examined the efficacy of 2-chlorodeoxyadenosine (2-CDA) in the treatment of refractory inhibitors to factor VIII in persons without hemophilia. The drug was administered to 6 patients at a dose of 0.1 mg/kg as a 24-hour continuous infusion for a total of 7 days each cycle. An average of 3 immunosuppressive regimens per patient had been administered prior to enrollment in this study. The median inhibitor titer against human and porcine factor VIII before treatment with 2-CDA was 31 Bethesda units (BUs) and 9 BU, respectively. The median inhibitor titer against human and porcine factor VIII after treatment was 3.5 BU and 1.5 BU, respectively. The median time to reach nadir inhibitor titer in this study was 137 days, whereas the median time to reach a 50% increase in factor VIII was 117 days. No major toxicity was observed in any patient in this study. Patients with acquired inhibitors to factor VIII refractory to conventional immunosuppressive therapy may respond favorably to 2-CDA.
MIP-1α and MIP-1β differentially mediate mucosal and systemic adaptive immunity
Authors: Lillard James W. , Singh Udai P. , Boyaka Prosper N. , Singh Shailesh , Taub Dennis D. , McGhee Jerry R. 
Published: January 2003

AbstractMacrophage inflammatory protein-1α (MIP-1α) and MIP-1β are distinct but highly homologous CC chemokines produced by a variety of host cells in response to various external stimuli and share affinity for CCR5. To better elucidate the role of these CC chemokines in adaptive immunity, we have characterized the affects of MIP-1α and MIP-1β on cellular and humoral immune responses. MIP-1α stimulated strong antigen (Ag)–specific serum immunoglobulin G (IgG) and IgM responses, while MIP-1β promoted lower IgG and IgM but higher serum IgA and IgE antibody (Ab) responses. MIP-1α elevated Ag-specific IgG1 and IgG2b followed by IgG2a and IgG3 subclass responses, while MIP-1β only stimulated IgG1 and IgG2b subclasses. Correspondingly, MIP-1β produced higher titers of Ag-specific mucosal secretory IgA Ab levels when compared with MIP-1α. Splenic T cells from MIP-1α– or MIP-1β–treated mice displayed higher Ag-specific Th1 (interferon-γ [IFN-γ]) as well as selective Th2 (interleukin-5 [IL-5] and IL-6) cytokine responses than did T cells from control groups. Interestingly, mucosally derived T cells from MIP-1β–treated mice displayed higher levels of IL-4 and IL-6 compared with MIP-1α–treated mice. However, MIP-1α effectively enhanced Ag-specific cell-mediated immune responses. In correlation with their selective effects on humoral and cellular immune responses, these chemokines also differentially attract CD4+ versus CD8+ T cells and modulate CD40, CD80, and CD86 expressed by B220+ cells as well as CD28, 4-1BB, and gp39 expression by CD4+ and CD8+ T cells in a dose-dependent fashion. Taken together, these studies suggest that these CC chemokines differentially enhance mucosal and serum humoral as well as cellular immune responses.
A site involving the “hybrid” and PSI homology domains of GPIIIa (β3-integrin subunit) is a common target for antibodies associated with quinine-induced immune thrombocytopenia
Authors: Peterson Julie A. , Nyree Contessa E. , Newman Peter J. , Aster Richard H. 
Published: January 2003

AbstractDrug-dependent antibodies (DDAbs) can cause the precipitous destruction of platelets if a patient is exposed to the drug for which the antibodies are specific. The molecular character of the epitopes recognized is poorly understood, and the mechanism by which drugs promote tight binding of these antibodies to platelet glycoproteins without linking covalently to protein or antibody is not yet known. We studied a group of quinine-dependent antibodies that react with human glycoprotein IIIa (GPIIIa; β3-integrin subunit) but fail to recognize rat GPIIIa, despite close homology between the 2 proteins. By characterizing reactions of these antibodies with human/rat GPIIIa chimeras and selected GPIIIa mutants, we found that each of 3 quinine-dependent antibodies requires a 17-amino acid sequence in the newly recognized “hybrid” and PSI homology domains of GPIIIa for drug-dependent binding. Disulfide bonds are required to stabilize the target epitope. Monoclonal antibody AP3, which blocks the binding of these DDAbs to GPIIIa, was found to require a more limited stretch of the same peptide for its reaction with the glycoprotein. The findings suggest this region of GPIIIa may be a favored target for quinine-dependent antibodies and may provide a basis for further studies to elucidate the molecular basis of glycoprotein–drug–antibody interaction.
Follicular lymphoma grade 3B includes 3 cytogenetically defined subgroups with primary t(14;18), 3q27, or other translocations: t(14;18) and 3q27 are mutually exclusive
Authors: Bosga-Bouwer Anneke G. , van Imhoff Gustaaf W. , Boonstra Ronald , van der Veen Anneke , Haralambieva Eugenia , van den Berg Anke , de Jong Bauke , Krause Vanessa , Palmer Martin C. , Coupland Robert , Kluin Philip M. , van den Berg Eva , Poppema Sibrand 
Published: January 2003

Abstract
Chromosomal translocations involving t(14;18)(q32;q21) and the chromosome 3q27 region are common in B-cell non-Hodgkin lymphoma of germinal center cell origin. Grade 3B follicular lymphoma (FL), consisting almost exclusively of centroblasts, is a distinct subgroup of follicular lymphomas that has more in common clinically with the aggressive diffuse large B-cell lymphomas than with their indolent FL grade 1 and 2 counterparts. We studied the cytogenetic and molecular genetic aberrations by classic cytogenetics, polymerase chain reaction, Southern blot hybridization, and fluorescence in situ hybridization, with special emphasis on t(14;18), affecting bcl-2, and 3q27 rearrangement, affecting bcl-6, in 32 cases of FL grade 3B. Three distinctive subgroups were identified based upon the existence of breakpoint 3q27, a translocation t(14;18), or the absence of both. Group I involved a t(14;18) and no 3q27 aberrations (n = 13); group II was without a t(14;18) and without 3q27 aberrations (n = 9), but had other cytogenetic aberrations; and group III was without a t(14;18) but with aberrations involving 3q27 (n = 10). None of the FL grade 3B cases harbored both a t(14;18) and 3q27 aberration. These results, in particular the finding of a mutual exclusiveness of bcl-2 and bcl-6 rearrangement, indicate at least 3 different pathways of oncogenesis in FL grade 3B. FL grade 3B with bcl-2 rearrangement probably is part of the same entity as the other follicular lymphomas (1, 2, 3A), whereas the cases with 3q27 abnormalities or other unrelated translocations are more closely related to the majority of diffuse large-cell lymphomas of germinal center cell origin.
Decreased phosphorylation of protein kinase B and extracellular signal-regulated kinase in neutrophils from patients with myelodysplasia
Authors: Fuhler Gwenny M. , Drayer A. Lyndsay , Vellenga Edo 
Published: January 2003

AbstractNeutrophils from patients with myelodysplastic syndrome (MDS) show a disturbed differentiation pattern and are generally dysfunctional. To study these defects in more detail, we investigated reactive-oxygen species (ROS) production and F-actin polymerization in neutrophils from MDS patients and healthy controls and the involvement of N-formyl-L-methionyl-L-lucyl-L-phenylaline (fMLP) and granulocyte macrophage–colony-stimulating factor (GM-CSF)–stimulated signal transduction pathways. Following fMLP stimulation, similar levels of respiratory burst, F-actin polymerization, and activation of the small GTPase Rac2 were demonstrated in MDS and normal neutrophils. However, GM-CSF and G-CSF priming of ROS production were significantly decreased in MDS patients. We subsequently investigated the signal transduction pathways involved in ROS generation and demonstrated that fMLP-stimulated ROS production was inhibited by the phosphatidylinositol 3 kinase (PI3K) inhibitor LY294002, but not by the MAPK/ERK kinase (MEK) inhibitor U0126. In contrast, ROS production induced by fMLP stimulation of GM-CSF–primed cells was inhibited by LY294002 and U0126. This coincides with enhanced protein kinase B (PKB/Akt) phosphorylation that was PI3K dependent and enhanced extracellular signal-regulated protein kinase 1 and 2 (ERK1/2) phosphorylation that was PI3K independent. We demonstrated higher protein levels of the PI3K subunit p110 in neutrophils from MDS patients and found that though the fMLP-induced phosphorylation of PKB/Akt and ERK1/2 could also be enhanced by pretreatment with GM-CSF in these patients, the degree and kinetics of PKB/Akt and ERK1/2 phosphorylation were significantly disturbed. These defects were observed despite a normal GM-CSF–induced signal transducer and activator of transcription 5 (STAT5) phosphorylation. Our results indicate that the reduced priming of neutrophil ROS production in MDS patients might be caused by a disturbed convergence of the fMLP and GM-CSF signaling routes.
Dynamics of GPIIb/IIIa-mediated platelet-platelet interactions in platelet adhesion/thrombus formation on collagen in vitro as revealed by videomicroscopy
Authors: Patel Dipti , Väänänen Heikki , Jiroušková Markéta , Hoffmann Thomas , Bodian Carol , Coller Barry S. 
Published: January 2003

Abstract
The conventional description of platelet interactions with collagen-coated surfaces in vitro, based on serial static measurements, is that platelets first adhere and spread to form a monolayer and then recruit additional layers of platelets. To obtain dynamic information, we studied gravity-driven platelet deposition in vitro on purified type 1 collagen by video phase-contrast microscopy at 22°C. With untreated human and wild-type mouse platelets, soon after the initial adhesion of a small number of “vanguard” platelets, “follower” platelets attached to the spread-out vanguard platelets. Follower platelets then adhered to and spread onto nearby collagen or over the vanguard platelets. Thus, thrombi formed as a concerted process rather than as sequential processes. Treatment of human platelets with monoclonal antibody (mAb) 7E3 (anti–GPIIb/IIIa (αIIbβ3) + αVβ3) or tirofiban (anti–GPIIb/IIIa) did not prevent platelet adhesion but nearly eliminated the deposition of follower platelets onto vanguard platelets and platelet thrombi. Similar results were obtained with Glanzmann thrombasthenia platelets. Wild-type mouse platelets in the presence of mAb 1B5 (anti–GPIIb/IIIa) and platelets from β3-null mice behaved like human platelets in the presence of 7E3 or tirofiban. Deposition patterns of untreated human and wild-type mouse platelets were consistent with random distributions under a Poisson model, but those obtained with 7E3- and tirofiban-treated human platelets, 1B5-treated mouse platelets, or β3-null platelets demonstrated a more uniform deposition than predicted. Thus, in this model system, absence or blockade of GPIIb/IIIa receptors interferes with thrombus formation and alters the pattern of platelet deposition.