bluuebunny/crossref_metadata_2025_split huggingface dataset:
Engraftment of human synovium into severe combined immune deficient mice. Migration of human peripheral blood T cells to engrafted human synovium and to mouse lymph nodes.
Authors: Rendt K E , Barry T S , Jones D M , Richter C B , McCachren S S , Haynes B F 
Published: December 2022

Abstract
To determine the feasibility of using the C.B-17 scid/scid (severe combined immune deficient, SCID) mouse as a recipient of human synovial xenografts, we have engrafted human synovium under the renal capsule of SCID mice, and determined synovial graft survival and histologic characteristics 4 to 7 wk after tissue implantation. Both normal and inflammatory synovial tissue grew well in SCID mice and maintained histologic and phenotypic components of the fresh synovial tissue before implantation. However, the number of T cells in synovial grafts decreased after implantation. To determine whether leukocytes could migrate to human synovial xenografts, either allogenic or autologous PBMC were injected in the peritoneum of SCID mice bearing synovial xenografts. We found that 7 days after i.p. injection of autologous or allogeneic PBMC, injected T cells had selectively migrated to human synovial grafts and to SCID mouse lymph nodes. Our data demonstrate that normal and inflammatory human synovial tissues will grow in SCID mice and serve as recipients for autologous and allogenic peripheral blood human T cells injected i.p. into engrafted mice.
CD4+8- and CD4-8+ mature thymocytes require different post-selection processing for final development.
Authors: Petrie H T , Strasser A , Harris A W , Hugo P , Shortman K 
Published: December 2022

Abstract
Two primary types of TCR-alpha/beta+ T cells are found in the peripheral lymphoid system; CD4+8- T cells, with MHC-class II restricted TCR, and CD4-8+ T cells, which are MHC-class I restricted. Both lineages develop in the thymus from a series of common precursors. However, the precise stage at which they diverge, and the combination of factors that regulates such divergence, are not well defined. The up-regulation of CD3/TCR to high mature levels is thought to be an early event associated with positive selection for self-MHC recognition. Using purified cells from bcl-2 transgenic mice in order to overcome the limitations imposed by cell death on normal thymocytes, we find that a minor subset of CD4+8+ thymocytes expressing high levels of CD3/TCR gives rise to both CD4+8- and CD4-8+ mature cells upon intrathymic transplantation, but only to CD4-8+ in culture. Thus, in addition to demonstrating the dual lineage potential of this subset, these findings show that additional post-selection processing events are required for the production of mature thymocytes, and that CD4+8- and CD4-8+ subsets differ in the types of processing required.
Priming does not change promoter sequence requirements for IFN induction or correlate with the expression of IFN regulatory factor-1.
Authors: Rosztoczy I , Pitha P M 
Published: December 2022

Abstract
Pretreatment of L929 cells with IFN enhances Sendai virus-mediated induction of IL-6, TNF-alpha, and IFNA and IFNB genes. The priming effect could be demonstrated at both the RNA and protein levels and the former did not require cellular protein synthesis. Priming increased the Sendai virus-mediated induction of a murine IFNA4 promoter-chloramphenicol acetyltransferase gene hybrid plasmid (A4CAT) in transiently transfected cells, and deletion analysis showed that the identical DNA sequence was required for the inducibility in primed and unprimed cells. Cotransfection of A4CAT plasmid with interferon regulatory factor-1 (IRF-1) expression plasmid increased CAT expression, however, the IRF-1-mediated expression was further enhanced by priming. These results show that the identical inducible element present in the promoter region of IFNA4 gene is required for both the inducibility and the priming effect; however, no direct correlation between the enhancement of expression of the IRF-1 gene and enhancement of expression of IFN, IL-6, and TNF-alpha genes in the primed cells was observed. We suggest that priming facilitates inducer-mediated posttranscriptional modulation of various transcriptional factors that play a role in stimulation of transcription of these genes.
Extensive allelic polymorphism in the CDR2-like region of the miniature swine CD4 molecule.
Authors: Gustafsson K , Germana S , Sundt T M , Sachs D H , LeGuern C 
Published: December 2022

Abstract
MHC class II polymorphism is well documented whereas only minimal polymorphism has been reported for the CD4 molecule with which it interacts. We report on the structural basis of an allelic polymorphism of the CD4 molecule in miniature swine. Eleven of 13 nucleotide differences between the 2 alleles cause amino acid replacements. A majority of these replacements are clustered in a region protruding as a loop structure, termed Ig CDR2-like, from the surface of the amino terminal domain. This part of the human CD4 appears to comprise the binding site for the human immunodeficiency virus gp120 protein. The loop structure has also been implicated in the binding of CD4 to MHC class II, but this is currently a matter of some controversy. Our previous results have indicated that the porcine CD4 polymorphism, that we now show is situated in this loop, does not significantly affect the binding to class II. However, because the polymorphism appears to have been selected for and is situated in a very exposed part of the molecule, it is likely to be of functional significance.
Evolving T cell responses in murine schistosomiasis. Th2 cells mediate secondary granulomatous hypersensitivity and are regulated by CD8+ T cells in vivo.
Authors: Chensue S W , Warmington K S , Hershey S D , Terebuh P D , Othman M , Kunkel S L 
Published: December 2022

Abstract
The dynamics of T cell maturation and regulation were examined during the granulomatous response to Schistosoma mansoni eggs under conditions of primary (PRIM), secondary vigorous (VIG), and secondary immunomodulated (MOD) immunity. The patterns of VIG and MOD GR (GR) formation were established in naive CBA mice by transfer of lymphoid cells from S. mansoni-infected donors at the VIG and MOD stages of infection. Sequential production of IFN, IL-2, and IL-4 was assessed at the GR and in draining lymph nodes (LN) to determine the participation of Th1 (IFN-producing) and Th2 (IL-4/IL-5-producing) cells. The PRIM GR produced IFN in the growth phase (2-16 days) and IL-4 was detected only after lesions were established (16-24 days). The PRIM LN showed coincident production of IFN, IL-2, and IL-4 on day 4 followed by mainly IL-4 and IL-2 production on day 8, consistent with Th2 differentiation via a Th0 precursor. The VIG GR produced high levels of IL-4 in the growth phase (4-8 days) although IFN remained at modest levels. The VIG LN showed increased cytokine levels consistent with an anamnestic response and again the pattern suggested Th2 differentiation from Th0 cells. The MOD mice had abrogated GR IL-4 levels and arrested Th2 differentiation in LN. In vitro mix studies indicated that the impaired cytokine production was not due to direct suppression. The role of Ts cells was next explored by T cell subset depletion. Pan-T cell depletion of VIG cells profoundly abrogated IL-4 production although CD8+ cell depletion augmented GR area by 70% as well as local and regional IL-4 production by 100 to 150%. Similarly, CD8+ cell depletion of MOD cells augmented GR size and IL-4 production but the response was less than corresponding VIG mice, suggesting that Th activity was reduced in MOD mice. Transfer studies indicated that CD8+ cells inhibited Th2 maturation in LN. Thus, the schistosome egg GR demonstrated a Th1-like pattern in the PRIM response followed by a Th2 pattern in the VIG stage and abrogated Th2 activity in the MOD stage. Finally, the phenomenon of "spontaneous modulation" likely represents the cumulative action of CD8+ cells which steadily erode the Th population.
IL-4 release by human leukemic and activated normal basophils.
Authors: Arock M , Merle-Béral H , Dugas B , Ouaaz F , Le Goff L , Vouldoukis I , Mencia-Huerta J M , Schmitt C , Leblond-Missenard V , Debre P 
Published: December 2022

Abstract
Recently, authors have addressed the ability of human basophils to produce IL-4. We report here the detection of significant serum IL-4 levels in a case of acute transformation of chronic myelogenous leukemia with a predominant basophilic cell population. Leukemic basophils were isolated from patients' PBMC and assayed for their IL-4-mRNA expression and their ability to secrete this cytokine in vitro. Leukemic basophilic cells (&gt; 90% toluidine blue positive) but not other PBMC expressed IL-4-mRNA, contained IL-4 protein, and secreted this cytokine. These cells had a spontaneous IL-4 secretion ability, without a need for an exogenous activator. Meanwhile, IL-4 release was significantly increased following leukemic cell activation through Fc epsilon RI-ligation or by Ca2+ ionophore. IL-4 and its mRNA were also detected in leukemic basophils from three other chronic myelogenous leukemia patients with moderate basophilia (13, 14, and 23% basophils in PBMC). To confirm these data in normal human cells, we have developed a method to obtain large numbers of purified basophils from human bone marrow cell cultures. In contrast to leukemic basophils, normal cells required in vitro activation through Fc epsilon RI ligation or by Ca2+ ionophore to express and secrete IL-4. Leukemic and normal basophils secreted histamine following in vitro activation, but were negative for tryptase. These data thus demonstrate the in vivo and in vitro ability of human basophils to produce IL-4.
Induction of MHC class II on human polymorphonuclear neutrophils by granulocyte/macrophage colony-stimulating factor, IFN-gamma, and IL-3.
Authors: Gosselin E J , Wardwell K , Rigby W F , Guyre P M 
Published: December 2022

Abstract
Polymorphonuclear neutrophils (PMN) have long been thought to be short-lived, terminally differentiated cells incapable of synthesizing significant levels of protein, with their primary function being phagocytosis and the release of cytotoxic compounds. More recently, it has been demonstrated that PMN can produce a number of functionally diverse substances, including IL-1, IL-6, and IL-8. Although PMN express class I MHC Ag, it has not been definitely demonstrated that they can synthesize and express class II Ag. This would suggest that, although PMN can indirectly assist in the induction of an immune response through production of cytokines, they are incapable of acting as APC for CD4+ Th cells. We show that, in the presence of a defined medium (AIM V), human serum, and granulocyte-CSF, nearly 100% of isolated PMN can survive for up to 2 days in vitro. We also show that PMN express MHC class II when present as bystander cells in a monocyte/T cell Ag presentation assay for 44 h. In addition, granulocyte/macrophage CSF (GM-CSF), IFN-gamma, and IL-3 can induce class II on pure cultures of PMN, with GM-CSF appearing to be the most potent of the three cytokines. Furthermore, induction of class II on PMN is distinctly donor dependent, with PMN from some donors repeatedly showing very high, and others very low, induction of class II when treated with GM-CSF. Their potential to express class II suggests that PMN could play a significant role in immunoregulation and disease pathogenesis. The variation in class II induction on PMN from individual donors might explain previous failures to detect class II induction on PMN and could be a factor in the varied susceptibility of different individuals to autoimmune and inflammatory disorders such as the production of antibodies to PMN cytoplasmic components.
Characterization of the immunosuppressive effects of nitric oxide in graft vs host disease.
Authors: Hoffman R A , Langrehr J M , Wren S M , Dull K E , Ildstad S T , McCarthy S A , Simmons R L 
Published: December 2022

Abstract
The generation of nitric oxide (.N = O) during in vitro assays involving lymphocyte-macrophage interaction can result in profound inhibition of lymphocyte proliferation. The present study examined whether .N = O synthesis plays a role in the suppression observed in immune function assays during graft vs host disease (GvHD). By using a parent to F1 model to induce GvHD (C57BL/6J to C57BL/6J x DBA 2J F1), a mild but transient increase in serum NO2- plus NO3- levels was observed on day 12 after inoculation. Resident peritoneal macrophages obtained from mice with GvHD demonstrated enhanced .N = O synthesis in response to LPS, compared with control F1 peritoneal macrophages. Similarly, when splenocytes from GvHD mice were cultured with Con A or LPS enhanced supernatant NO2- levels were observed, compared with control F1 mice. Addition of NG-monomethyl-L-arginine (NMA), a competitive inhibitor of .N = O synthesis, resulted in decreased NO2- levels and greatly enhanced proliferation in response to Con A. Addition of NMA to LPS-stimulated cultures did not enhance proliferation, perhaps as the result of the paucity of B cells in the GvHD population. LPS-induced .N = O synthesis by GvHD splenocytes was blocked by anti-IFN-gamma mAb, whereas Con A-induced .N = O synthesis was relatively unaffected by similar concentrations of anti-IFN-gamma mAb, suggesting different mechanisms of induction of .N = O synthesis. A proliferative response of splenocytes from mice with GvHD to third-party alloantigen was not detectable, even in the presence of NMA. The suppression observed when splenocytes from GvHD animals were added to control TNP-modified self cultures was partially reversed in the presence of NMA. These results demonstrate that .N = O synthesis in both splenocyte and peritoneal macrophage populations from GvHD mice is enhanced, revealing that in vivo priming of macrophages for .N = O synthesis occurs during GvHD. Some, but not all, in vitro tests of immune function by using GvHD splenocytes are suppressed by the generation of .N = O.
Membrane cofactor protein (CD46) protects cells predominantly from alternative complement pathway-mediated C3-fragment deposition and cytolysis.
Authors: Kojima A , Iwata K , Seya T , Matsumoto M , Ariga H , Atkinson J P , Nagasawa S 
Published: December 2022

Abstract
Membrane cofactor protein (MCP) cDNA was transfected into Chinese hamster ovarian tumor (CHO) cells and the functional properties of the expressed protein were studied. Cells adherent to flasks were essential for continuous expression of MCP on CHO cells. If the cells were maintained in noncoated flasks, MCP expression was markedly reduced but upon being transferred to coated flasks reexpressed the protein. MCP expressed on CHO cells had the expected m.w., approximately 50 kDa, and possessed factor I-cofactor activity. By a propidium iodide incorporation assay and by 51Cr release assay, antibody-sensitized CHO cells expressing MCP were protected from C-mediated cytotoxicity. The inhibition of lytic activity correlated with a decrease in C3 deposition. This host cell protective activity was exerted efficiently for the alternative pathway. The classical pathway was not blocked by MCP unless the cells were presensitized with low concentrations of antibody. These results imply that MCP primarily protects host cells from alternative pathway-mediated C3 targeting. In a pathologic state such as autoimmune diseases, the binding of an autoantibody to a target may overcome this protective effect of MCP via the classical pathway.
Regulation of expression of the ligand for CD40 on T helper lymphocytes.
Authors: Castle B E , Kishimoto K , Stearns C , Brown M L , Kehry M R 
Published: December 2022

Abstract
Activated Th cells deliver contact-dependent signals to resting B lymphocytes that initiate and drive B cell proliferation. Recently, a ligand for the B lymphocyte membrane protein, CD40, has been identified that delivers contact-dependent Th cell signals to B cells. A dimeric soluble form of CD40 was produced and used to further characterize the regulation of expression of the CD40 ligand. Expression of the CD40 ligand was rapidly induced after Th lymphocyte activation, and its stability depended upon whether Th cells were activated with soluble or plastic-bound stimuli. Th cells activated with soluble stimuli rapidly turned over cell-surface CD40 ligand whereas Th cells activated with plastic-bound stimuli exhibited more stable CD40 ligand expression for up to 48 h. Removal of activated Th cells from the plastic-bound stimulus resulted in a rapid turnover of CD40 ligand, suggesting that continuous stimulation could maintain CD40 ligand expression. Ligation by soluble CD40 could also stabilize expression of CD40 ligand on the Th cell surface. Both CD40 ligand and IL-2 were transiently synthesized from 1 to 12 h after Th cell activation and had similar kinetics of synthesis. In Con A-activated Th cells newly synthesized CD40 ligand exhibited an initial high turnover (1.5 h t1/2) and after 5 h of Th cell activation became more stable (10-h t1/2). In Th cells activated with plastic-bound anti-CD3, CD40 ligand exhibited a similar biphasic turnover except that the rapid turnover phase began significantly later. This delay could allow more time for newly synthesized CD40 ligand to assemble or associate with other molecules and thus become stabilized on the cell surface. Newly synthesized CD40 ligand in Con A-activated Th cells appeared to not be efficient in delivering Th cell-dependent contact signals to resting B cells, implying the need for assembly or accessory proteins. Regulation of CD40 ligand expression was consistent with all the characteristics of Th cell-delivered contact signals to B cells and may contribute to the high degree of specificity in B cell responses.
Expression of merosin in the thymus and its interaction with thymocytes.
Authors: Chang A C , Wadsworth S , Coligan J E 
Published: December 2022

Abstract
Merosin is a 700 kDa multichain protein that has several properties in common with laminin, one of the major extracellular matrix proteins present in basement membranes. Both contain B1 and B2 light chains, but merosin has a distinct M-chain compared with the laminin A-chain. Merosin is present in the basement membrane of placenta, striated muscle, and peripheral nerve. Using the RT-PCR assay, we demonstrate that merosin, but not laminin, is also expressed in the thymus. A partial cDNA sequence of the mouse merosin M-chain was 88% identical to the human M-chain, and the deduced amino acid sequences were 95% identical. 18-24% of adult mouse thymocytes bound to human merosin in vitro. Mg2+, but not Ca2+, was essential for binding. Binding was inhibited by antibodies recognizing VLA alpha 6 or beta 1, suggesting that the VLA-6 integrin is a merosin receptor. An anti-beta 4 integrin subunit mAb failed to inhibit binding, suggesting that the alpha 6 beta 4 integrin was not involved. Thymocytes were fractionated into immature and mature populations based on their expression of the heat stable antigen, recognized by the J11d mAb. Virtually all thymocytes expressed VLA-6, but only immature thymocytes (J11d+) bound to meroson. PMA treatment did not significantly increase the binding of J11d+ thymocytes nor did induce binding in the mature J11d- population. In constrast, both splenic T cells and unseparated lymph node cells showed enhanced binding to merosin after PMA stimulation. The expression of merosin in the thymus and its selective interaction with immature thymocytes suggest that thymocyte-merosin interactions may play a role in T cell development.
Role of CD4+ and CD8+ cell subsets during amplification of natural T cell activity against IgG2ab in Igha mice and during induction of IgG2ab allotype suppression in Igha/b mice.
Authors: Majlessi L , Benaroch P , Denoyelle C , Bordenave G 
Published: December 2022

Abstract
Transfer into F1 Igha/b mice of splenocytes from Igha mice sensitized once against B cells from an Ighb congenic strain induces total, chronic, and IgG2ab (IgG2a of the Ighb haplotype)-specific allotype suppression in these recipients. We previously demonstrated that both the CD4+ and CD8+ T subsets were necessary for inducing suppression, but that CD8+, cells by themselves were sufficient for maintaining suppression. We have studied the suppression induction capacity of different mixtures of CD4+ and CD8+ subsets obtained by in vitro cytotoxic treatment of T splenocytes from normal or sensitized Igha mice, and we have established that suppression induction requires the cooperation between CD4+ and CD8+ populations, both of which have to be IgG2ab specific. In addition, Igha mice were sensitized in the absence of CD4+ or CD8+ cells by in vivo cytotoxic treatment performed before and after the sensitization in order to obtain an IgG2ab-specific CD4+ population that has arisen in the absence of CD8+ cells, and vice versa. We found that only IgG2ab-specific CD4+ cells from anti-CD8-treated mice (T'sens CD4+) had the ability to induce suppression in F1 Igha/b hosts. Nevertheless, the real effector cells in this suppression model display the CD8+ phenotype, as in vivo cytotoxic anti-CD8 treatment of Igha/b recipients of T'sens CD4+ abrogates the suppression induction capacity. Taken together, these results show that T'sens CD4+ have an important capacity to recruit CD8+ anti-IgG2ab effector cells from precursors that have been transferred with them into Igha/b hosts. These precursors are actually derived from the T'sens CD4+ cell preparation, because we have recently demonstrated that suppression is maintained by donor T cells throughout the recipient's life. CD4+ cells can have their anti-IgG2ab activity amplified only by means of target cells (i.e., B cells from Ighb congenic mice), whereas, in the absence of CD4+ cells, and despite the presence of target cells, CD8+ cells seem unable to acquire this amplified activity.
Two signals are required for negative selection of CD4+CD8+ thymocytes.
Authors: Page D M , Kane L P , Allison J P , Hedrick S M 
Published: December 2022

Abstract
Recent results indicate that two signals are required for activation of mature T cells. The first is delivered through the TCR, and the second is delivered through receptors that bind various ligands expressed on APC. For example, it has been shown that B7/BB1, which is expressed on many APC, can costimulate T cell activation by binding to CD28 or CTLA4, which are expressed on mature T cells. In contrast, little is known of the signals required for negative selection of autoreactive thymocytes. Thus, we have investigated this issue by using an in vitro culture system in which thymocytes from mice that are transgenic for a class II MHC-restricted TCR are cultured with murine fibroblast lines that express class II MHC. Under these conditions, CD4+CD8+ (DP) thymocytes undergo an Ag-dependent programmed cell death, which likely represents the negative selection of autoreactive thymocytes that would occur in an intact thymus. Using this culture system, we first found that both TCR- and APC-dependent stimuli were required in order to induce deletion of DP thymocytes. Anti-TCR antibodies alone did not cause deletion of DP cells, but merely induced a decrease in their expression of CD4 and CD8 to produce a DPdull phenotype. Addition of APC was then required for deletion of these DPdull cells. One obvious candidate for the costimulatory signal expressed by these APC was B7. Three different experimental approaches indicated, however, that B7 was not the APC-dependent signal required for deletion of DP thymocytes. Thus, these results suggest that negative selection of autoreactive thymocytes is a two-step process in which stimulation of the TCR causes downregulation of CD4 and CD8 on DP thymocytes, and then an unknown ligand expressed on APC stimulates a receptor on DP thymocytes to induce their deletion.