bluuebunny/crossref_metadata_2025_split huggingface dataset:
Lectin-like inhibition of immune complex receptor-mediated stimulation of neutrophils. Effects on cytosolic calcium release and superoxide production.
Authors: Sehgal G , Zhang K , Todd R F , Boxer L A , Petty H R 
Published: December 2022

Abstract
We have tested the role of lectin-like interactions, with particular emphasis on CR3, in insoluble immune complex (IC)-mediated activation of human polymorphonuclear leukocytes (PMN). The ability of IC to trigger intracellular Ca2+ release and O2- production by normal PMN, saccharide-treated cells, and CR3-deficient PMN (leukocyte adhesion deficiency, LAD, patients) were tested. When indo-1-labeled normal PMN were stimulated with IC in Ca(2+)-free buffer, intracellular Ca2+ rose from approximately 100 nM to approximately 230 nM. However, when LAD PMN were tested, a small rise in intracellular Ca2+ was observed. Because previous studies have shown that certain saccharides inhibit CR3-Fc gamma RIII co-capping, we tested a panel of saccharides to determine their ability to influence IC-mediated intracellular Ca2+ release. When normal PMN were exposed to 0.15 M N-acetyl-D-glucosamine (NADG), D-mannose, or alpha-methyl-mannoside, the Ca2+ response to IC was significantly reduced. However, addition of 0.15 M glucose, raffinose, sucrose, galactose, fructose, or sorbitol did not significantly affect the Ca2+ response, suggesting that the response was specific for certain saccharides. To test the physiologic consequences of these Ca2+ signals, we have examined the ability of saccharides to influence O2- production by normal PMN and the ability of LAD PMN to produce O2- upon triggering by IC. Normal PMN stimulated with IC generated 4.3 +/- 1.7 nmol/10(6) cells/30 min of O2-. In contrast, O2- production was inhibited by 0 to 20% by glucose, galactose, sucrose, sorbitol, fructose, and raffinose and &gt; or = 50% by NADG and mannose. LAD PMN, which display diminished Ca2+ signals, were found to produce O2- at 47 +/- 6% of control levels. NADG and mannose dose-response studies indicated that they cooperatively block O2-.
Construction of a bispecific antibody reacting with the alpha- and beta-chains of the human IL-2 receptor. High affinity cross-linking and high anti-proliferative efficiency.
Authors: Francois C , Boeffard F , Kaluza B , Weidle U H , Jacques Y 
Published: December 2022

Abstract
A bispecific antibody recognizing both the alpha- and beta-chains of the IL-2R was generated by sulfhydryl-directed chemical reassociation of monovalent Fab' fragments prepared from the anti-alpha mAb 33B3.1 (rat IgG2a) and from the anti-beta mAb A41 (mouse IgG1). Whereas the 33B3.1/A41 bispecific mAb (bi-mAb) binds to isolated alpha- and beta-chains with low affinity (Kd = 4 nM), its binding to cells co-expressing the two chains shows both low and high affinity components. The high affinity-binding sites (Kd = 100 pM) most probably correspond to the cross-linking by the bi-mAb of alpha- and beta-chains, whereas the low affinity component corresponds to the excess of alpha-chains. High affinity binding of bi-mAb on activated T cells is observed at 37 degrees C and not at 4 degrees C, suggesting that i) the two chains are dissociated at 4 degrees C in the absence of ligand and ii) the mechanism of bi-mAb catalyzed cross-linking of these two chains is temperature dependent. In contrast to parental 33B3.1 and A41 IgG, which recognize single positive (alpha + and beta +, respectively) and double positive alpha +/beta + cells with similar affinities, the 33B3.1/A41 bi-mAb is specific for activated alpha +/beta + cells with respect to its high affinity binding. In contrast to A41, which does not affect IL-2-induced proliferation of 4AS cells or anti-CD3-activated PBL, and to 33B3.1, which do inhibit proliferation but only partially and at high doses, the bi-mAb showed full blocking efficiencies at low concentrations (IC50 of 300 to 400pM) corresponding to the formation of high affinity alpha/bi-mAb/beta complexes. These half-maximal effects were observed at 10-fold lower concentrations than when using a combination of equimolar concentrations of parental 33B3.1 and A41 IgG. Because of their specificity and high blocking efficiencies, anti-alpha/anti-beta bi-mAb may constitute a better alternative for IL-2R-directed immunosuppression.
Thymic microenvironmental abnormalities and thymic selection in NZB.H-2bm12 mice.
Authors: Watanabe Y , Naiki M , Wilson T , Godfrey D , Chiang B L , Boyd R , Ansari A , Gershwin M E 
Published: December 2022

Abstract
We have taken advantage of an extensive panel of mAb directed to thymic epithelial and nonepithelial stromal cells to examine the expression of these Ag from day 16 of gestation through 6 mo of age in NZB(H-2d), NZB.H-2b, NZB.H-2bm12, C57BL/6(H-2b), and C57BL/6.H-2bm12 mice. In addition, by triple color flow cytometry we have examined the expression of cell surface markers defining distinct stages of intrathymic T cell maturation. New Zealand mice demonstrated three abnormalities. MTS 10 normally stains thymic medullary and subcapsular epithelium. However, New Zealand mice demonstrated striking irregular medullary epithelial cell shape whereas their subcapsular epithelium remained normal. Moreover, New Zealand mice, unlike controls, were found to have MTS 10+ epithelial cells within the cortex. Additionally, MTS 39 and MTS 44, which normally stain reticular cortical epithelium, produced a striking different staining pattern in New Zealand mouse thymus, including the presence of large cortical epithelial cellfree regions, so-called "cortical holes." MTS 33 normally stains cortical thymocytes but in New Zealand mice, there was a severe decrease of MTS 33+ cells. There was also an increase of CD3lowCD4+CD8+ cells in NZB mice, which may include many predeletion thymocytes. Finally, there was a significant increase of CD3highCD4+CD8- cells in NZB.H-2bm12 and C57BL/6.H-2bm12 mice compared with NZB.H-2b and C57BL/6(H-2b) mice. We postulate that these microenvironmental alterations in NZB mice contribute to and reflect altered T cell differentiation, thereby predisposing them to autoimmune disease. Moreover, the increased proportion of CD3highCD4+CD8- cells associated with the H-2bm12 mutation may be involved in the remarkably different profiles of disease between NZB.H-2b and NZB.H-2bm12 mice.
Differential action of cycloheximide and activation stimuli on transcription of tumor necrosis factor-alpha, IL-1 beta, IL-8, and P53 genes in human monocytes.
Authors: Osipovich O A , Fegeding K V , Misuno N I , Kolesnikova T S , Savostin I K , Sudarikov A B , Voitenok N N 
Published: December 2022

Abstract
In the present study we have analyzed superinduction of TNF-alpha mRNA and enhancement of TNF-alpha gene transcription by cycloheximide (Chx) in human blood monocytes isolated by continuous Percoll gradient and activated in vitro. In the same monocyte cultures, we have compared the rate of gene transcription of TNF-alpha, IL-1 beta, IL-8, and the P53-antioncogene under the influence of plastic adherence, Staphylococcus aureus Cowan 1 (SAC), and Chx added at different times of monocyte culture. It was shown that the cytokine genes have low or negligible transcriptional activity in freshly isolated monocytes, whereas P53 gene transcription was constant in freshly isolated and in vitro-stimulated cells. Transcription of the IL-1 beta and IL-8 genes was induced by adherence and was not more enhanced by SAC. Transcription of the TNF-alpha gene was not induced by adherence. Chx added at the beginning of the monocyte culture did not block TNF-alpha or IL-1 beta gene transcription. IL-8 gene transcription, however, was abrogated by Chx. Addition of SAC to monocyte culture containing Chx caused significant enhancement of TNF-alpha gene transcription. Addition of Chx after 2.5 or 4 h of SAC activation caused "superinduction" of TNF-alpha mRNA and enhancement of TNF-alpha gene transcription. The data imply that TNF-alpha gene transcription in activated human monocytes might be regulated by both positive and negative regulatory factors that differ in their stability and protein synthesis dependence. In addition, results demonstrate that TNF-alpha, IL-1 beta, IL-8, and p53 genes in human monocytes are differently regulated.
Genomic cloning and promoter analysis of macrophage inflammatory protein (MIP)-2, MIP-1 alpha, and MIP-1 beta, members of the chemokine superfamily of proinflammatory cytokines.
Authors: Widmer U , Manogue K R , Cerami A , Sherry B 
Published: December 2022

Abstract
Macrophage inflammatory protein (MIP)-2, MIP-1 alpha, and MIP-1 beta all belong to the newly recognized "chemokine" superfamily of structurally related, activation-inducible cytokines with inflammatory and growth regulatory activities. We report the isolation and sequencing of genomic clones for murine MIP-2 and murine MIP-1 beta, and analyze their regulatory sequences in comparison with each other and with several other members of the chemokine family. The murine (mu)MIP-2 genomic clone displays the canonical four exon/three intron structure typical of other genes in the chemokine alpha subfamily (e.g., IL-8). Potential cis regulatory elements in the proximal promoter region were highly conserved between muMIP-2 and its three most closely related human homologs: human (hu)GRO-alpha, huGRO-beta, and huGRO-gamma. A mouse macrophage cell line, RAW 264.7, was transfected with a growth hormone reporter construct driven by a proximal fragment of the muMIP-2 5' promoter, and nested deletion mutant analysis localized the LPS responsive element to a region that contains a conserved NF kappa B consensus motif and lies 51 to 70 bp 5' from the transcription start site. In contrast to that of MIP-2, the muMIP-1 beta genomic clone exhibited the three exon/two intron structure characteristic of the chemokine beta family members (e.g., MCP-1). A comparison of the promoters for muMIP-1 beta and muMIP-1 alpha reveals a conserved CK-1 element, but transient expression studies in RAW 264.7 macrophages with proximal fragments of either the muMIP-1 beta or the muMIP-1 alpha 5' promoter fused to a human growth hormone reporter gene link LPS-inducibility in both to promoter segments near to, but not identical with, the consensus CK-1 sequence. Proximal 5' promoter fragments cloned from both the MIP-1 alpha and MIP-1 beta genes unexpectedly conferred constitutive expression on the fused reporter gene sequences in macrophage-like cells, but initial 5' deletion analysis did not link this responsiveness to known sequence motifs. The muMIP-1 beta promoter, but not the muMIP-1 alpha promoter, was constitutively active in B16 mouse melanoma cells, and both promoters were active in the myelomonocytic cell line WEHI 3B(A)d-, the muMIP-1 alpha promoter being three times stronger.
Role of 55- and 75-kDa tumor necrosis factor membrane receptors in the regulation of intercellular adhesion molecules-1 expression by HL-60 human promyelocytic leukemia cells in vitro.
Authors: Abe Y , Gatanaga M , Osuka Y , Kimura S , Burger R A , Granger G A , Gatanaga T 
Published: December 2022

Abstract
Most human cells express two TNF and lymphotoxin (LT) membrane receptors (TNF-R), of 55 and 75 kDa. The regulatory effect of these two receptors on intercellular adhesion molecules (ICAM-1) expression was examined in various human cell lines in vitro, including human lymphokine-activated killer T cells (T-LAK) cells and HL-60 cells. Rabbit antihuman TNF-R antisera specific for each receptor were employed as probes to selectively stimulate 55- and 75-kDa TNF/LT membrane receptor production. These antisera compete with TNF/LT binding to each specific cell membrane receptor and have been found to bind to specific membrane receptors on various human cell lines in vitro. In the present study, we demonstrated biologic activity for anti-55-kDa TNF-R antiserum. For example, antibodies that bind to the 55-kDa TNF-R caused cytolysis of HeLa and ME-180 human cervical cancer cells and induced proliferation of MRC-5 human fibroblasts. In contrast, however, anti-75-kDa TNF-R antiserum demonstrated no bioactivity in these assays. In addition, no synergy or costimulation was observed when a combination of both anti-55- and anti-75-kDa TNF-R antisera were tested in these assay systems. Anti-55-kDa TNF-R antiserum up-regulated ICAM-1 expression on human HL-60, T-LAK, and THP-1 cells, whereas anti-75-kDa TNF-R antiserum had no effect. Unexpectedly, however, ICAM-1 expression was greatly enhanced by the addition of anti-75-kDa TNF-R to the anti-55-kDa TNF-R containing culture. This enhancing effect was also observed with human T-LAK cells and THP-1 monocytic leukemia cell, in vitro.
EBV peptide epitope sensitization restores human cytotoxic T cell recognition of Burkitt's lymphoma cells. Evidence for a critical role for ICAM-2.
Authors: Khanna R , Burrows S R , Suhrbier A , Jacob C A , Griffin H , Misko I S , Sculley T B , Rowe M , Rickinson A B , Moss D J 
Published: December 2022

Abstract
The pathogenesis of EBV+ Burkitt's lymphoma (BL) suggests evasion of the CTL response against EBV. Two important features of this tumor have been previously suggested to explain this immune evasion, (a) absence/low expression of cellular adhesion molecules and (b) restricted expression of EBV latent Ag. To determine the relative importance of these features in relation to evasion of EBV-specific CTL, a group of BL cell lines with variable expression of the aforementioned phenotypic characteristics were assayed for specific CTL lysis after exogenous addition of EBV peptide epitopes. In spite of down-regulated expression of the adhesion molecules LFA-1, LFA-3, and/or ICAM-1, peptide-sensitized BL cells were recognized and lysed by EBV-specific CTL. Moreover, there was no significant difference between the CTL lysis of the BL cells and that of adhesion molecule-positive control cells over a wide range of peptide epitope concentrations. Blocking experiments with mAb to individual adhesion molecules suggested that virus-specific CTL recognition of lymphoblastoid cell lines was dependent on an intact LFA-3/CD2 pathway. In contrast, the CTL recognition of peptide-sensitized BL cells was critically dependent on the LFA-1/ICAM pathway, with an insignificant contribution by CD2/LFA-3. The consistently high expression of ICAM-2 on all BL cell lines suggests that the accessory function in CTL recognition of these cells is mediated by the LFA-1/ICAM-2 pathway. Thus, down-regulation of LFA-1, LFA-3, and/or ICAM-1 expression on BL cells does not provide an absolute barrier to tumor cell recognition by virus-specific CTL. The ability of virus-specific CTL to recognize peptide epitope-sensitized BL cells as efficiently as normal cells has demonstrated the importance of latent Ag expression in the CTL control of EBV+ tumors.
Altered regulation of IL-6 production with normal aging. Possible linkage to the age-associated decline in dehydroepiandrosterone and its sulfated derivative.
Authors: Daynes R A , Araneo B A , Ershler W B , Maloney C , Li G Z , Ryu S Y 
Published: December 2022

Abstract
Normal aging in humans has been recently shown to be accompanied by reduced control over production of the multifunctional cytokine IL-6. This cytokine was reported to be quantitatively elevated in most serum samples obtained from "normal" elderly humans. In the present investigation, we report that IL-6 levels are elevated in serum samples obtained from aged mice, and its spontaneous production could also be easily detected in culture supernatants of unstimulated lymphoid cells obtained from aged, but not mature, adult donors. Spontaneous production of IL-6 was consistently observed in culture supernatants of lymphoid cells from both the spleen and mesenteric lymph nodes from aged donors, but was absent from supernatants derived from their peripheral lymph nodes. In aged mice, the reduced regulation of IL-6 production could be effectively prevented and/or reversed by supplementing aging animals with dehydroepiandrosterone sulfate, a steroid hormone whose endogenous production is known to decline with advancing age in all species tested. It was also established that serum obtained from old dehydroepiandrosterone sulfate-treated mice contained lower (normal) levels of serum amyloid P substance (an acute phase reactant), reduced levels of serum Ig (all classes and isotypes) and lower titers of tissue-specific autoantibodies than untreated aged controls. Therefore, a number of well described, age-related conditions, some of which could be contributing to the pathologic phenotype of old age, may actually represent secondary effects to this age-associated change in IL-6 production.
Genesis of human oncolytic natural killer cells from primitive CD34+CD33- bone marrow progenitors.
Authors: Lotzová E , Savary C A , Champlin R E 
Published: December 2022

Abstract
We have found that fully functional CD56+CD3- NK cells can be generated from highly enriched populations of CD34+ human bone marrow progenitors in long term bone marrow culture (LTBMC) with IL-2. Strong lytic activity against K-562 cells was observed after 2 to 3 weeks of culture and coincided with the appearance of CD56+CD3- large granular lymphocytes, which comprised 55 to 84% of cells. In contrast, lymphocytes generated from CD34- bone marrow cells were predominantly CD56-CD3+ T cells. The phenotypic profile of NK cells generated in LTBMC differed from that of IL-2-cultured peripheral blood NK cells. Specifically, a lower percentage of LTBMC-derived NK cells coexpressed CD16, CD2, CD7, and CD8 Ag. NK cells generated in LTMBC proliferated actively, with an expansion index ranging from two- to 200-fold. Furthermore, NK cells were generated from the CD34+CD33- hematopoietic subset, which had been depleted of the myeloid-committed progenitors (CD34+CD33+). Generation of cytotoxic NK cells in LTBMC was dependent on the dose of IL-2; although CD56+CD3- NK cells were generated in LTBMC supplemented with a broad range of doses (10 to 10(3) U/ml) of IL-2, the acquisition of full cytotoxic function required a high concentration of IL-2 (10(3) U/ml). These observations demonstrate the IL-2-driven differentiation of NK cells from early bone marrow progenitors and indicate that LTBMC may provide an excellent model for studies of NK cell lineage and differentiation in normal and pathologic conditions.
A common sequence motif near nonhomologous recombination breakpoints involving Ig sequences.
Authors: Chou C L , Morrison S L 
Published: December 2022

Abstract
Analysis of nonhomologous recombination events at the Ig loci revealed that a four base sequence, 5'-CCAG-3', or its complement, 5'-CTGG-3', is present within seven nucleotides in 12 of the 13 examined recombination breakpoints. Statistical analysis of the data indicates that this occurrence has a probability of less than 10(-5) of occurring by chance. This sequence is infrequently found at nonhomologous recombination breakpoints in non-Ig sequences, suggesting that its contribution may be either Ig- or B cell-specific. Intriguingly, this tetranucleotide is also found to be associated with the breakpoints of VH gene replacement and isotype switching, suggesting that common pathways may be involved in all three B cell processes.
Simultaneous transfer of four functional genes from the HLA class II region into mammalian cells by fusion with yeast spheroplasts carrying an artificial chromosome.
Authors: Demmer L A , Chaplin D D 
Published: December 2022

Abstract
Gene transfer using yeast artificial chromosome (YAC) clones provides an opportunity to study the expression of several linked genes within an environment more closely approximating their normal chromosomal context. A YAC clone spanning 330 kb of the HLA class II region from centromeric of TAP 1 to telomeric of HLA-DQA1 was retrofitted by homologous recombination with a neomycin plasmid targeted either to an Alu repeat sequence within the YAC genomic insert or to the Ura-3 gene within the right arm of the YAC vector. The modified YAC clones were transferred to Chinese hamster ovary or L cells by spheroplast fusion. Eight of 14 Alu-retrofitted and 10 of 15 right arm-retrofitted neomycin clones retained the six human loci known to be encoded by the YAC as well as portions of the left and right YAC vector arms. All tested L cell transformants showed IFN-gamma-inducible TAP 1 and TAP 2 mRNA expression. Two of eight analyzed clones expressed HLA-DQB mRNA and one of four expressed HLA-DQA. Cells expressing both the HLA-DQA and -DQB mRNA showed HLA-DQ cell surface expression. These studies establish the feasibility of introducing groups of functional genes into mammalian cells by spheroplast fusion with a single YAC clone.
Studies on antigen binding by intact and hinge-deleted chimeric antibodies.
Authors: Horgan C , Brown K , Pincus S H 
Published: December 2022

Abstract
A matched set of chimeric IgG1 and IgG4 antibodies were used to investigate the role of the IgG hinge in binding to Ag with differing space between the epitopes. Antibodies bearing identical V regions and either IgG1 or IgG4 C regions were engineered with and without hinges. We measured the binding of these antibodies to the peptide CYYYEEEEY and to CYYYEEEEY-BSA conjugates with decreasing numbers of peptides per BSA molecule. We earlier showed that V region differences in antibodies could affect Ag binding patterns in solid-phase but not solution-phase assays; however, both types of assay yielded similar results for the hinge-deleted antibodies. Binding of CYYYEEEEY-BSA by hinge-deleted and intact IgG1 was similar, but intact IgG1 bound free peptide better than did hinge-deleted IgG1. Intact IgG4 antibody bound less well to CYYYEEEEY and CYYYEEEEY-BSA than did IgG1 but, surprisingly, hinge-deleted IgG4 showed better binding than did intact IgG4 and was more like the IgG1 antibodies in binding affinity. Thus, the IgG4 hinge may impart a structural constraint that prevents high affinity binding to Ag. The hinge-deleted IgG4 antibody did not activate C, although it bound Ag similarly to IgG1. This study is the first to address the effect of the IgG hinge on Ag binding by using well defined Ag with different epitope densities. Our results may provide an explanation for the apparent low affinity of IgG4 antibodies.
Regulation of IL-5 in onchocerciasis. A critical role for IL-2.
Authors: Steel C , Nutman T B 
Published: December 2022

Abstract
The cytokine profiles of PBMC obtained from individuals "immune" to Onchocerca volvulus infection were compared to those from infected individuals. The immune individuals had significantly higher levels of both IL-2 and IL-5 in response to parasite Ag than did those individuals with active infection (mean IL-2 = 1.3 and 0.138 U/ml, respectively; mean IL-5 = 973 and 147.4 pg/ml, respectively), and there was a direct correlation between the production of IL-2 and IL-5. To examine the mechanism underlying the possible association between these two cytokines in patients infected with onchocerciasis, reverse transcription followed by polymerase chain reaction was used to measure IL-5 mRNA. In response to rIL-2, IL-5 mRNA appeared as early as early as 3 h after stimulation of patient PBMC, reaching a peak at 24 h; further, this response was inhibited with neutralizing antibodies to IL-2. IL-2 was unable to induce mRNA expression for IL-4, IFN-gamma, IL-10, or granulocyte-macrophage-CSF. To assess whether IL-2 was specifically responsible for the up-regulation of Ag-induced IL-5 production in patients with onchocerciasis, IL-5 mRNA expression was measured in PBMC stimulated with parasite Ag. Up-regulation of IL-5 mRNA was seen in all patients (peaking at 72 h) in response to Ag stimulation and was found to be independent of proliferation to Ag; in addition, this up-regulation was specifically inhibited by neutralizing anti-IL-2 antibodies. Further, the primary source of IL-5 mRNA was determined to be CD4+ T cells. These findings suggest that IL-2 production is required to induce IL-5 and further implicates IL-5 as a possible mediator of protection in onchocerciasis.