bluuebunny/crossref_metadata_2025_split huggingface dataset:
CD18-dependent and -independent mechanisms of neutrophil emigration in the pulmonary and systemic microcirculation of rabbits.
Authors: Doerschuk C M , Winn R K , Coxson H O , Harlan J M 
Published: December 2022

Abstract
Neutrophil (PMN) migration in the systemic and pulmonary circulation of rabbits was compared by using different inflammatory stimuli to determine the role of the leukocyte adhesion complex, CD11/CD18, in each of these vascular beds. The adhesion complex was blocked by administering the anti-CD18 mAb 60.3. The data show that mAb 60.3 blocks PMN emigration into inflammatory foci in the abdominal wall produced by implanting sponges containing either hydrochloric acid, Streptococcus pneumoniae, Escherichia coli endotoxin, or PMA. mAb 60.3 also inhibited PMN emigration in response to peritoneal instillation of S. pneumoniae. The effect of mAb 60.3 on PMN emigration in the lungs varied depending upon the stimulus. PMN failed to migrate into the PMA-induced pneumonia; however, mAb 60.3 pretreatment only partially inhibited endotoxin-induced pneumonia and did not inhibit S. pneumoniae or hydrochloric acid-induced pneumonias. PMN lavaged from the alveolar spaces in the Streptococcal pneumonia had similar quantities of mAb 60.3 bound to their surfaces as the circulating PMN. We conclude that the CD11/CD18 complex mediates PMN adherence in the systemic circulation. However, PMN adherence in the pulmonary circulation may occur by either CD18-dependent or -independent mechanisms that are specific to the inciting stimulus.
CD18-deficient cells respond to lipopolysaccharide in vitro.
Authors: Wright S D , Detmers P A , Aida Y , Adamowski R , Anderson D C , Chad Z , Kabbash L G , Pabst M J 
Published: December 2022

Abstract
The CD11/CD18 complex of leukocyte adhesion molecules has been shown to bind LPS on the surface of gram negative bacteria and LPS-coated erythrocytes (J. Exp. Med. 164:1876, 1986). LPS elicits several responses in leukocytes including secretion of TNF-alpha and IL-1 beta, and priming for enhanced release of oxygen radicals such as superoxide anion. To determine if expression of CD18 molecules is necessary for these effects of LPS, we have examined the responses of leukocytes from CD18-deficient patients. Three of the patients in this study are characterized for the first time here, and three were described elsewhere. Monocytes and macrophages from CD18-deficient patients synthesized normal amounts of IL-1 beta and TNF-alpha in response to LPS. Further, PMN and monocytes from CD18-deficient patients showed normal priming for enhanced release of superoxide anion in response to LPS. Although a small contribution of CD18 molecules to some responses cannot be ruled out by our data, we may conclude that CD18 molecules are not essential for cellular responses to LPS.
Characterization of the receptor for tumor necrosis factor (TNF) and lymphotoxin (LT) on human T lymphocytes. TNF and LT differ in their receptor binding properties and the induction of MHC class I proteins on a human CD4+ T cell hybridoma.
Authors: Andrews J S , Berger A E , Ware C F 
Published: December 2022

Abstract
TNF-alpha and lymphotoxin (LT or TNF-beta) are structurally related cytokines that share several proinflammatory and immunomodulatory activities. The shared biologic activities of TNF and LT have been attributed to their binding to a common cell surface receptor(s). We observed that rTNF enhanced the expression of MHC class I proteins on the human T cell hybridoma, II-23.D7, however LT was largely unable to regulate MHC expression. To determine the molecular basis of this disparity between LT and TNF the receptor binding characteristics of rTNF and rLT were investigated by direct and competitive radioligand assays on the II-23.D7 T hybridoma, and for comparison, anti-CD3 activated human T lymphocytes. Specific 125I-rTNF binding to the II-23.D7 line revealed a single class of sites with a Kd = 175 pM and 3000 sites/cell; anti-CD3 activated T cells exhibited specific TNF binding with similar properties. The relationship of receptor occupancy to the induction of MHC class I Ag yielded a hyperbolic curve indicating a complex relationship between rTNF binding and biologic response. LT appeared to function like a partial agonist in that rLT was 10- to 20-fold less effective than rTNF in competitively inhibiting 125I-rTNF binding on the II-23.D7 line. Scatchard type analysis revealed a single class of low affinity binding sites for 125I-rLT. No differences in the competitive binding activity of rTNF and rLT were observed on the anti-CD3-activated T cells. Receptors for rTNF and rLT were immunoprecipitated from the II-23.D7 and activated T cells with anticytokine antibodies after cross-linking of radioiodinated rTNF or rLT to intact cells by using chemical cross-linking reagents. Analysis of the cross-linked adducts by SDS-PAGE and autoradiography indicated a major adduct of 92 kDa for rTNF and 104 kDa for rLT. Enzymatic digestion with neuraminidase or V8 protease revealed a unique structure to these adducts consistent with the cross-linking of a single chain of cytokine to a cell surface glycoprotein. rTNF inhibited the formation of the 104-kDa adduct formed with 125I-rLT on the II-23.D7 line, indicating these two cytokines bind to the same receptor of approximately 80 kDa. These results suggest that the disparate activities of LT and TNF to induce MHC class I proteins on the II-23.D7 cells are, in part, associated with a modified state of a common receptor.
Constitutive production of human interleukin for DA cells/leukemia inhibitory factor by human tumor cell lines derived from various tissues.
Authors: Gascan H , Anegón I , Praloran V , Naulet J , Godard A , Soulillou J P , Jacques Y 
Published: December 2022

Abstract
The cytokine HILDA (human IL for DA cells)/LIF (leukemia inhibitory factor), previously reported to trigger the proliferation of the DA1.a cell line was purified to homogeneity from the culture supernatant of the 5637 bladder carcinoma cell line by using a four step procedure, including cationic exchange chromatography at pH 6, Con A affinity chromatography, reverse phase HPLC, and gel filtration HPLC. The purified radiolabeled protein was analyzed in SDS-PAGE and a single band with a molecular mass of 43 kDa was revealed. The iodinated material was then tested in a radioreceptor assay using the M1 cell line as a second target cell line. The binding of the natural 125I hormone was abrogated in a dose dependent and specific fashion by either natural and rHILDA. The limit of signal detection of displacement for the radiolabeled ligand by unlabeled sample was found to be 0.05 ng/ml. The proliferative DA1.a assay and the M1 radioreceptor assay were used to analyze the HILDA content of 17 human tumor cell line culture supernatants, and 12 among them were spontaneously secreting a detectable level of LIF. The secreted amount of HILDA was largely enhanced by treating the cell line with 30 to 80 nM PMA; in these conditions a 10 to 20x increase in the detected amount was observed. The specificity of the detected signal was reinforced by analyzing the mRNA expression of HILDA in the tumor cell lines. The secreting cell lines were found to express various forms of LIF transcripts with a major specie at 3.8 kb.
Mac-1 (CD11b/CD18) mediates adherence-dependent hydrogen peroxide production by human and canine neutrophils.
Authors: Shappell S B , Toman C , Anderson D C , Taylor A A , Entman M L , Smith C W 
Published: December 2022

Abstract
Human neutrophils exposed to protein-coated polystyrene or cultured endothelial monolayers produce large quantities of H2O2 in response to soluble stimuli that elicit little or no secretion of reactive oxygen species from cells in suspension. To characterize the mechanisms involved in this adherence-dependent respiratory burst, we have investigated the possible role of one integrin known to participate in the adhesion of neutrophils to endothelial cells, CD11b/CD18 (Mac-1). H2O2 production was examined with chemotactic factor-stimulated human and canine neutrophils exposed to protein-coated surfaces and cultured human and canine endothelial cells. The two protein-coated surfaces used were type I collagen-coated glass or plastic, a surface to which neither human nor canine neutrophils adhered, and keyhole limpet hemocyanin (KLH)-coated glass or plastic, a surface to which human and canine neutrophils adhered only after chemotactic stimulation. FMLP-stimulated human neutrophils and platelet activating factor-stimulated canine neutrophils failed to produce detectable H2O2 when in contact with type I collagen, but secreted large amounts of H2O2 when adherent to KLH or endothelial cell monolayers. FMLP-stimulated neutrophils from patients with CD18-deficiency failed to adhere to any of these surfaces and failed to produce H2O2 under these conditions. mAb reactive with CD18 and CD11b were equally effective in markedly inhibiting the adhesion of normal human neutrophils to these surfaces and markedly inhibited the production of H2O2. A mAb reactive with CD18 blocked adhesion of stimulated canine neutrophils, and mAb directed against both CD18 and CD11b blocked H2O2 production by canine neutrophils on KLH and endothelium. A nonbinding mAb and a mAb reactive with CD11a did not inhibit H2O2 production of human cells on KLH or endothelial monolayers, and nonbinding and binding control mAb did not inhibit H2O2 production by canine neutrophils. These results indicate that Mac-1 (CD11b/CD18) can mediate adhesion-dependent H2O2 production by human and canine neutrophils exposed to chemotactic factors.
Requirement of lipophosphoglycan for intracellular survival of Leishmania donovani within human monocytes.
Authors: McNeely T B , Turco S J 
Published: December 2022

Abstract
The function of the lipophosphoglycan of Leishmania donovani parasites was investigated in human peripheral monocytes. In contrast to wild-type L. donovani which grow in monocytes, incubation of monocytes with two variant lines of L. donovani, defective in lipophosphoglycan expression, resulted in the entry of the variant cells into the monocytes and their subsequent destruction. Passive transfer of lipophosphoglycan to the variant cells led to prolonged survival in monocytes. These results indicate that lipophosphoglycan is required by the parasite for intracellular survival. To investigate one possible protective role of the glycoconjugate, preincubation of monocytes with a suspension of lipophosphoglycan and subsequent treatment of the cells with PMA or opsonized zymosan resulted in an attenuation of the oxidative burst; the attenuation effect was concentration dependent on the glycoconjugate and independent of preincubation time. Moreover, hydrophobic beads, coated with lipophosphoglycan, were phagocytized by monocytes and found to inhibit oxygen consumption in monocytes activated with PMA. These results suggest a possible relationship between the absence of lipophosphoglycan in the variant parasites and their inability to survive within monocytes. Although the precise molecular basis remains to be elucidated, the ability of lipophosphoglycan to impair the microbial oxidative response may be a contributing factor in its requirement for intracellular survival.
Host-specific evasion of the alternative complement pathway by schistosomes correlates with the presence of a phospholipase C-sensitive surface molecule resembling human decay accelerating factor.
Authors: Pearce E J , Hall B F , Sher A 
Published: December 2022

Abstract
Schistosoma mansoni parasites recovered from the blood stream were found to be nonactivators of the alternative complement pathway (ACP) when exposed to sera of homologous but not heterologous host species. Schistosomes could be converted into activators of the homologous ACP by treatment with phospholipase C. Antibodies to either human or guinea pig decay accelerating factor (DAF), a 70-kDa glycosylphosphatidylinositol anchored membrane glycoprotein which controls ACP activation on the mammalian cell plasma membrane, bound to the surface of immature schistosomes and immunoprecipitated a molecule of similar molecular mass from detergent extracts of surface iodinated parasites. Phospholipase C treatment drastically reduced the reactivity of the worms with the anti-DAF antibodies. These data suggest that schistosomes evade the ACP by inserting functional host DAF into their surfaces, possibly through adsorption of the molecule's lipophilic diacyglycerol membrane anchor moiety into the outer lipid bilayer of the parasite.
Mouse V lambda x gene sequence generates no junctional diversity and is conserved in mammalian species.
Authors: Sanchez P , Marche P N , Rueff-Juy D , Cazenave P A 
Published: December 2022

Abstract
The lambda x, a new mouse Ig lambda L chain, is produced by rearrangement of the V lambda x, J lambda 2, and C lambda 2 gene segments. The V lambda x amino acid sequence is as divergent to other V lambda as to Vk gene sequences. Additionally, its third hypervariable region (CDR3) is four amino acids longer than those of all other variable gene segments of murine L chain. We have cloned and sequenced the germ-line V lambda x gene and found that the unexpected CDR3 length is encoded by the V lambda x gene. Junctional diversity is prevented by a TAA termination codon localized at the V lambda x 3' extremity. Moreover, we show a striking conservation of the V lambda x sequence in various mammalian species. Portions of the V lambda x sequence display more than 70% of nucleotide sequence identity with rabbit and human variable regions. These results suggest that V lambda x predated the divergence of mammalian species.
Differential regulation of Ca2+ mobilization in human thymocytes by coaggregation of surface molecules.
Authors: Deusch K , Daley J F , Levine H , Languet A J , Anderson P , Schlossman S F , Blue M L 
Published: December 2022

Abstract
Variations in intracellular Ca2+ levels in developing thymocytes are likely to play a major role in both the activation-associated differentiation of thymocytes and in the selection or clonal deletion of cells. Here we examine the role of CD4, CD8, CD2, and CD45 in the regulation of intracellular Ca2+ levels in mature and immature thymocytes. Mature and immature thymocytes, distinguished on the basis of their CD5 expression, were analyzed simultaneously for their ability to mobilize Ca2+ after coaggregation of their CD3/TCR with other thymic surface Ag. Flow cytometric analysis by using Indo-1 showed that coaggregation of CD4, CD8, and CD2 with CD3/TCR clearly enhances a minimal signal delivered via CD3/TCR on immature thymocytes. Coaggregation with class I MHC had no discernible effect. The responsiveness of immature thymocytes correlated strictly with CD3 surface expression, such that loss of responsiveness occurred with reduced CD3 cell-surface density. However, even thymocytes with very low CD3 expression were able to respond to triggering via CD3 under optimal conditions, indicating that the CD3 signal-transducing mechanism is functional on early thymic cells. Intracellular increases in Ca2+ concentrations induced via CD3, could effectively be inhibited by cross-linking of CD45 and CD3 on immature thymocytes. Although triggering via CD2 alone induced a strong Ca2+ flux, prolonged incubation with activating anti-CD2 antibodies made thymocytes refractory to subsequent triggering. Refractoriness was associated with partial loss of surface CD3 and CD3 zeta. Our results indicate that thymic surface Ag are differentially involved in the regulation of intracellular Ca2+ levels in immature as well as mature thymocytes.
Metabolic activity is necessary for activation of T suppressor cells by B cells.
Authors: Elkins K L , Stashak P W , Baker P J 
Published: December 2022

Abstract
Ag-primed B cells must express cell-surface IgM, but not IgD or Ia Ag, and must remain metabolically active, in order to activate suppressor T cells (Ts) specific for type III pneumococcal polysaccharide. Ag-primed B cells that were gamma-irradiated with 1000r, or less, retained the ability to activate Ts; however, Ag-primed B cells exposed to UV light were not able to do so. gamma-Irradiated and UV-treated Ag-primed B cells both expressed comparable levels of cell-surface IgM, and both localized to the spleen after in vivo transfer; neither could proliferate in vitro in response to mitogens. By contrast, gamma-irradiated primed B cells were still able to synthesize proteins, whereas UV-treated primed B cells could not. These findings suggest that in order for Ag-primed B cells to activate Ts, they must a) express cell-associated IgM (sIgM) antibody bearing the idiotypic determinants of antibody specific for type III pneumococcal polysaccharide, and b) be able to synthesize protein for either the continued expression of sIgM after cell transfer, or for the elaboration of another protein molecule that is also required for the activation of Ts; this molecule does not appear to be Ia Ag.
Characterization of the neutral aminopeptidase activity associated to the mouse thymocyte-activating molecule.
Authors: Gorvel J P , Vivier I , Naquet P , Brekelmans P , Rigal A , Pierres M 
Published: December 2022

Abstract
We previously characterized a dimeric, Mr = 115,000, developmentally regulated mouse T cell-activating molecule (THAM). We show in this report that the THAM-specific mAb H194-112 exhibits strong reactivity with several nonlymphoid tissues including polarized enterocytes from small intestine, kidney cortical tubuli, and liver bile ductuli, as well as kidney glomeruli and lung alveoloar pneumocytes. Both the tissue distribution and the structural features of THAM made it likely that this molecule belongs to the ectoenzyme family. This was confirmed by the following experimental evidence: 1) the H194-112+ molecules from enterocyte brush borders (BB) or M14.T thymoma cells were recognized by several antisera specific for intestinal aminopeptidase N (AP-N); 2) mAb H194-112 was found to immunodeplete the AP-N activity from both thymic or enterocyte BB detergent extracts; 3) the hydrophilic, Mr = 115,000 form obtained by papain treatment of thymoma or enterocyte BB could be immunopurified on H194-112 column and exhibited, after hypotonic elution, strong enzymatic activity on the AP-N substrates (i.e., leucyl or alanyl beta-derivatives); 4) mAb H194-112 was found to inhibit the AP-N activity when assayed on alanyl but not leucyl beta-naphthylamide substrate; and 5) preincubation of AP-N with mAb H194-112 prevented the inhibiting effects of bestatin and D,L-methionyl hydroxamate on AP-N activity. These data add a new member to the list of functional ectoenzymatic markers of lymphoid cells (i.e., CD10, CD13, CD26, CD55, and CD73). In view of the known immunomodulating properties of bestatin, one may speculate that the T cell-activating effects of mAb H194-112 is related to an impairment of a surface enzymatic function regulating lymphoid cell activation.
Increased lymphocyte adherence to human arterial endothelial cell monolayers in the context of allorecognition.
Authors: Colson Y L , Markus B H , Zeevi A , Duquesnoy R J 
Published: December 2022

Abstract
The interactions of alloreactive T lymphocytes with the vascular endothelium were studied in an in vitro model of lymphocyte adherence to cultured human arterial endothelial cell (HAEC) monolayers. Donor-primed lymphocytes (DPL) were shown to have significantly greater adherence to donor HAEC than were third-party primed lymphocytes. Limiting dilution analysis of adherent DPL showed an enrichment of donor-reactive lymphocytes compared with nonadherent DPL. This study examines the allospecific nature of this increased lymphocyte adherence. HAEC constitutively express class I HLA Ag and can be induced by IFN-gamma to express class II Ag. DPL adherence to class I+ HAEC was inhibited only in the presence of mAb directed against class I Ag. DPL adherence to class I+ and class II+ HAEC was inhibited in the presence of mAb directed against class I and class II Ag. Class I- and class II-specific adherence was also shown to involve CD8 and CD4 molecules, respectively, whereas lymphocyte function-associated Ag do not appear to play a major role in long term alloreactive lymphocyte adherence to HAEC. These findings suggest that alloreactive lymphocyte adherence to HAEC is mediated by two mechanisms. One is based on allorecognition, primarily of HLA Ag, and the other is related to presumably non-Ag-specific interactions between activated lymphocytes and the vascular endothelium. The studies presented provide evidence to suggest that HLA-specific lymphocyte adherence to endothelium may significantly contribute to the development of alloreactive lymphocyte infiltrates within the allograft.
Aqueous humor contains transforming growth factor-beta and a small (less than 3500 daltons) inhibitor of thymocyte proliferation.
Authors: Granstein R D , Staszewski R , Knisely T L , Zeira E , Nazareno R , Latina M , Albert D M 
Published: December 2022

Abstract
The anterior chamber of the eye is an immunologically privileged site in which allografts survive longer than at other body sites. In this regard, it is relevant that aqueous humor (AH) inhibits lymphocyte proliferation. In order to analyze AH for specific substances that inhibit thymocyte proliferation, samples of human AH, murine AH, and rhesus monkey AH were added to cultures of thymocytes stimulated by IL-1 or IL-2 in the presence of PHA. All samples of AH tested had potent inhibitory activity on thymocyte proliferation in this system. Inhibitory activity was lost by heating AH to 80 degrees C for 1 h. Dialysis of murine AH indicated that species smaller than 3500 Da were capable of mediating this activity; we have termed the factor(s) responsible for this "small inhibitory factor(s) of AH." Retentate, containing species larger than 3500 Da, retained inhibitory activity, but less than nondialyzed AH. Assays for PGE2 demonstrated that murine and human AH contained small quantities of PGE2. These quantities were insufficient to inhibit thymocyte proliferation in our assay system. Furthermore, AH from mice treatend with indomethacin had full inhibitory activity. Assays for transforming growth factor beta (TGF-beta) after acid activation demonstrated significant quantities of latent TGF-beta within human and murine AH which could be largely neutralized by antisera to TGF-beta. Active TGF-beta "activity" was also present without acid activation in samples of AH at a level approximately 20% that of latent TGF-beta. However, most of this "activity" could not be neutralized by antisera to TGF-beta. AH contains factors capable of limiting thymocyte proliferation.