bluuebunny/crossref_metadata_2025_split huggingface dataset:
CD5+ peritoneal B cells express high levels of membrane, but not secretory, C mu mRNA.
Authors: McIntyre T M , Holmes K L , Steinberg A D , Kastner D L 
Published: December 2022

Abstract
We used in situ hybridization to study Ig mRNA levels in murine peritoneal and splenic B cells. Ig mRNA production fell into three distinct groups: low, intermediate, and high. Splenic B cells primarily exhibited low levels characteristic of resting B cells or high Ig mRNA levels characteristic of plasma cells. In contrast, a significant fraction of peritoneal B cells exhibited intermediate Ig mRNA levels. Intermediate Ig mRNA was T cell dependent in that congenic nu/nu mice had far fewer peritoneal cells expressing the intermediate Ig message than their wild type counterparts. CD5+ CD11b+ IgMbright+ peritoneal B cells were found to be mainly responsible for the production of intermediate Ig mRNA levels. The peritoneal CD5- CD11b+ IgMbright+ "sister" B cell subpopulation contained a lower percentage of intermediate Ig mRNA-producing B cells. CD5-CD11b-IgMdull+ "conventional" B cells produced negligible levels of Ig mRNA, comparable to those of unfractionated splenic B cells. Northern analysis showed that the majority of Ig mRNA expressed in the peritoneum is of the membrane rather than the secreted form. Consistent with that result, in short-term culture, peritoneal cells showed markedly less Ig secretion than did spleen cells. These studies describe novel Ig mRNA expression by peritoneal B cells and emphasize that within the peritoneal cavity, B cells do not tend to become antibody-secreting cells.
Position of the rearranged V kappa and its 5' flanking sequences determines the location of somatic mutations in the J kappa locus.
Authors: Weber J S , Berry J , Manser T , Claflin J L 
Published: December 2022

Abstract
Somatic hypermutation is known to occur in the VJ kappa exon and its flanking sequences, yet little is known about the hypermutation mechanism or its exact target within the rearranged locus. Mutations may occur at the same frequency, spanning a region from the leader intron to 3' of J kappa 5, regardless of which J is chosen for VJ rearrangement. Another possibility is that mutations may be limited to the rearranged VJ kappa and its immediate flanking sequences. To distinguish between these possibilities, the JC introns of 21 alleles with V kappa rearranged to J kappa 1 were sequenced, and mutations were located. The frequency of mutations was determined for different sections of the intron and compared with the frequencies of mutations found in the JC intron of a set of VJ kappa 5 alleles. The results showed that mutations were concentrated in and around the rearranged VJ, regardless of whether J kappa 1 or J kappa 5 was used. These data imply that the hypermutational mechanism focuses on rearranged V genes.
Cytokine-induced enhancement of ICAM-1 expression results in increased vulnerability of tumor cells to monocyte-mediated lysis.
Authors: Webb D S , Mostowski H S , Gerrard T L 
Published: December 2022

Abstract
Pretreatment of the human melanoma cell line, A375, and the human colon carcinoma cell line, HT-29, with certain cytokines was found to increase the vulnerability of these cells to monocyte-mediated killing. This activity was found to correlate with increased expression of intercellular adhesion molecule-1 (ICAM-1) on the tumor cells and was blocked by anti-ICAM-1 antibodies. Both IFN-gamma and TNF induced large increases in the ICAM-1 expression on both cell lines and increased the susceptibility of the tumor cells to monocyte-mediated killing. IFN-alpha and IL-1 beta, however, induced only small increases in ICAM-1 expression and enhanced the lysis of the A375 cells but not the HT-29 cells by monocytes. These differences may be the result of a higher basal expression of ICAM-1 found on the A375 cells when compared with the HT-29 cells. These data indicate that regulation of ICAM-1 expression on tumor cells can alter the vulnerability of these cells to lysis by monocytes.
Defective thymic T cell activation by concanavalin A and anti-CD3 in autoimmune nonobese diabetic mice. Evidence for thymic T cell anergy that correlates with the onset of insulitis.
Authors: Zipris D , Lazarus A H , Crow A R , Hadzija M , Delovitch T L 
Published: December 2022

Abstract
In nonobese diabetic (NOD) mice, T cells play a major role in mediating autoimmunity against pancreatic islet beta-cells. We and others previously reported that age-related alterations in the thymic and peripheral T cell repertoire and function occur in prediabetic NOD mice. To study the mechanism responsible for these T cell alterations, we examined whether a defect exists in the thymus of NOD mice at the level of TCR-mediated signaling after activation by Con A and anti-CD3. We found that thymocytes from NOD mice respond weakly to Con A- and anti-CD3-induced proliferation, compared with thymocytes from control BALB/c, BALB.B, (BALB.B x BALB.K)F1, C57BL/6, and nonobese non-diabetic mice. This defect correlates with the onset of insulitis, because it can be detected at 7 to 8 weeks of age, whereas younger mice displayed a normal T cell responsiveness. Thymic T cells from (NOD x BALB/c)F1 mice, which are insulitis- and diabetes-free, exhibit an intermediate stage of unresponsiveness. This T cell defect is not due to a difference in the level of CD3 and IL-2R expression by NOD and BALB/c thymocytes, and both NOD CD4+ CD8- and CD4- CD8+ mature thymic T cells respond poorly to Con A. BALB/c but not NOD thymic T cells respond to Con A in the presence of either BALB/c or NOD thymic APC, suggesting that the thymic T cell defect in NOD mice is intrinsic to NOD thymic T cells and is not due to an inability of NOD APC to provide a costimulatory signal. The defect can be partially reversed by the addition of rIL-2 to NOD thymocytes. To determine whether a defect in signal transduction mediates this NOD thymic T cell unresponsiveness, we tested whether these cells elevate their intracellular free Ca2+ ion concentration in response to Con A. An equivalent Con A-induced increase in Ca2+ ion concentration in both NOD and BALB/c thymocytes was observed, suggesting a normal coupling between the CD3 complex and phospholipase C in NOD thymocytes. In contrast to their low proliferative response to Con A or anti-CD3, NOD thymocytes respond normally (i.e., as do BALB/c thymocytes) to the combinations of PMA plus the Ca2+ ionophore ionomycin and PMA plus Con A but weakly to Con A plus ionomycin. Our data suggest that the age-related NOD thymocyte unresponsiveness to Con A and anti-CD3 results from a defect in the signaling pathway of T cell activation that occurs upstream of protein kinase C activation.
Mechanistic studies of transforming growth factor-beta inhibition of IL-2-dependent activation of CD3- large granular lymphocyte functions. Regulation of IL-2R beta (p75) signal transduction.
Authors: Ortaldo J R , Mason A T , O'Shea J J , Smyth M J , Falk L A , Kennedy I C , Longo D L , Ruscetti F W 
Published: December 2022

Abstract
CD3- large granular lymphocyte (LGL) express constitutive levels of functional IL-2R beta. TGF-beta inhibited several IL-2R beta-mediated events in LGL, including IL-2-induced NK and lymphokine-activating factor activities, IFN-gamma gene expression and secretion, and IL-2R alpha expression. TGF-beta inhibited these IL-2-induced LGL functions in a dose-dependent and reversible manner. By contrast, TGF-beta had little effect on LGL IL-2R beta expression and TGF-beta receptors were not induced by IL-2. Studies were performed to examine binding and internalization of radiolabeled IL-2. These experiments demonstrated that the rapid binding and internalization of [125I]IL-2 was not altered in CD3- LGL pretreated with TGF-beta. These internalization studies indicated that the TGF-beta inhibition represented postreceptor-binding events in NK cells. Further studies were initiated to examine signaling events in CD3- LGL. When IL-2-induced tyrosine phosphorylation events were examined, significant inhibition was seen of selected phosphoproteins in TGF-beta-pretreated cells. In addition, the ability of TGF-beta to also inhibit IL-2 induction of LGL IL-2R alpha and IFN-gamma mRNA expression was consistent with the hypothesis that posttranscriptional mechanisms were unlikely to be affected by TGF-beta. Collectively, these data indicated that TGF-beta inhibited IL-2-induced CD3- LGL functions and suggested that TGF-beta inhibition occurs either at the level of specific tyrosine phosphorylation and/or IL-2-induced transcriptional control factors.
Mapping of the binding specificity for five monoclonal antibodies recognizing 3-deoxy-D-manno-octulosonic acid in bacterial lipopolysaccharides.
Authors: Lind S M , Kenne L , Lindberg A A 
Published: December 2022

Abstract
Mouse mAb were produced against the deep rough strains Salmonella minnesota R 595, Salmonella typhimurium SL 1102, and Escherichia coli D21f2 and screened by enzyme immunoassay against LPS of several chemotypes. Five antibodies were selected for their ability to bind to chemotype deep rough (Re) LPS which has two 3-deoxy-D-manno-octulosonic acid (Kdo) residues in its nonreducing end. Structurally verified oligosaccharides isolated from rough LPS and synthetic analogues of Kdo were used in an enzyme immunoassay inhibition test to determine the binding epitopes for the antibodies. According to their specificities, the antibodies could be divided into three groups. For two of the groups, the recognized structure was the alpha-Kdo (2----4) Kdo disaccharide and for one group the alpha-Kdo (2----4) alpha-Kdo beta-D-GlcN (1----6) alpha-D-GlcN tetrasaccharide, representing a partial structure of the Re LPS. Inhibition studies with synthetic analogues of Kdo showed that the anomeric configuration and the free carboxyl group of the Kdo residue are important features for antibody binding. Changes in the C-1 to C-6 region of the Kdo molecule do influence the antibody recognition considerably whereas changes in the exocyclic C-7 to C-8 region are of secondary importance. Calculation of the conformation of the inner core region showed that the alpha-Kdo (2----4) alpha-Kdo (2---- disaccharide was free and accessible in chemotype Re LPS, but that linkage of a L-glycero-D-manno-heptose to O-5 of the subterminal Kdo both changes the conformation of the Kdo-disaccharide and covers it thereby making it less accessible.
Complement-mediated killing of the Lyme disease spirochete Borrelia burgdorferi. Role of antibody in formation of an effective membrane attack complex.
Authors: Kochi S K , Johnson R C , Dalmasso A P 
Published: December 2022

Abstract
Lyme disease is a multisystemic illness caused by the spirochete Borrelia burgdorferi. In the absence of specific antibody, the spirochete is resistant to the bactericidal activity of C, despite the capacity of B. burgdorferi to activate both C pathways. We examined the mechanism of serum resistance by measuring the deposition of C3 and terminal C components on B. burgdorferi in the presence and absence of immune IgG. In normal human serum antibody-sensitized borreliae bound similar amounts of C3, and similar or increased amounts of C8 and C9, in comparison to unsensitized bacteria. However, at comparable levels of C3, C8, or C9 uptake, only sensitized bacteria were killed. The requirement of antibody for killing could not be explained by differences in the rate of C deposition or by differences in the C9 to C8 ratio in the membrane attack complex (MAC). We found that bacteria incubated in C5-depleted human serum, but not in C6-depleted serum, were killed when this treatment was followed by antibody and the missing C components. Bacteria were also killed by reactive lysis (C5b-9) provided that antibody was present. Therefore, the effect of bactericidal IgG occurred at the stage of C5b binding to the bacterial surface. Elution studies of bound C9 indicated that the MAC was stably bound to the outer membrane of B. burgdorferi, whether or not the bacteria were treated with antibody. However, treatment with 0.1% trypsin released 48% of 125I-C9 from the surface of unsensitized borreliae and 24% from IgG-sensitized cells, demonstrating that the presence of the antibody changed the accessibility to trypsin of C9 in the MAC. These results indicate that the effect of antibody in the killing process is not to enhance the rate or extent of initial or terminal component binding, but rather to alter the bacterial outer membrane to allow effective MAC formation.
Specificity of the mouse cytotoxic T lymphocyte response to adenovirus 5. E1A is immunodominant in H-2b, but not in H-2d or H-2k mice.
Authors: Rawle F C , Knowles B B , Ricciardi R P , Brahmacheri V , Duerksen-Hughes P , Wold W S , Gooding L R 
Published: December 2022

Abstract
The Ag specificity and MHC restriction of the CTL response to adenovirus 5 (Ad5) in three strains of mice, C57BL/10 (H-2b), BALB/c (H-2d), and C3H/HeJ (H-2k), were tested. Polyclonal Ad5-specific CTL were prepared by priming mice in vivo with live Ad5 virus followed by secondary in vitro stimulation of the spleen cells with virus-infected syngeneic cells. The Ad5-specific CTL were Db restricted in C57BL/10 and Kk restricted in C3H/HeJ. In BALB/c mice both Kd- and Dd/Ld-restricted CTL were detected. The polyclonal Ad5-specific CTL response in C57BL/10 mice is directed exclusively against the products of the E1A region, which comprises only 5% of the Ad5 genome. In BALB/c mice E1A is at best a very minor target Ag and in C3H/HeJ mice E1A is not recognized at all. Using the H-2 congenic mouse strains B10.BR (H-2k) and C3H.SW (H-2b) it was shown that the immunodominance of E1A is H-2 dependent. The 19-kDa glycoprotein encoded in the E3 region of Ad5, which binds to class I MHC in the endoplasmic reticulum and prevents its translocation to the cell surface, does not affect the specificity of the CTL response in C57BL/10 mice toward E1A. However, it affects the MHC restriction of the Ad5-specific response in BALB/c mice, selectively inhibiting generation of Kd-restricted CTL.
Guatemalan human onchocerciasis. II. Evidence for IgG3 involvement in acquired immunity to Onchocerca volvulus and identification of possible immune-associated antigens.
Authors: Boyer A E , Tsang V C , Eberhard M L , Zea-Flores G , Hightower A , Pilcher J B , Zea-Flores R , Zhou W , Reimer C B 
Published: December 2022

Abstract
Ag-specific isotypic differences in immune response to Onchocerca volvulus Ag were assessed for 778 long term residents of endemic Guatemalan areas by quantitative ELISA with 5-min incubation steps and immunoblot. The study population was separated into five groups based on clinical status: N+F+, N+F-, N-F+, N-F-H+, and N-F-H-, where N = O. volvulus adults (nodule), F = microfiladermia, and H = history of O. volvulus infection. A subset of 44 individuals with high exposure to onchocerciasis from the N-F-H- group were critically evaluated and designated as "putatively immune." IgG1 reactivity to O. volvulus Ag was elevated in the majority of infected persons, but not in putatively immune individuals. Specific IgG3 levels, however, were equally elevated in all groups. The majority of N+F- persons also had elevated IgG1 levels, but they were lower than those found in F+ persons. IgG3 reactivities to a group of antigens at 20 kDa (GP20) were seen in many uninfected persons and some N+F- persons. In contrast, most F+ persons, react to this Ag with IgG1 and not IgG3. A mangabey inoculated with the infectious larval stage of O. volvulus (L3), but showed no signs of infection, began to recognize GP20 at 2 wk postinoculation. Early recognition of GP20 was possibly elicited by the larval stage. Purified nodule Ag from N+F+ individuals contained GP20, however, identical nodule Ag prepared from N+F- individuals did not. These data suggest that GP20 Ag may be common to both uterine microfilaria and the infectious larval stages. The fact that GP20 is predominantly recognized by IgG3 in putatively immune persons and some N+F- persons suggests that this increased IgG3 activity may be important in acquired immunity to onchocerciasis.
Transforming growth factor-beta suppresses human B lymphocyte Ig production by inhibiting synthesis and the switch from the membrane form to the secreted form of Ig mRNA.
Authors: Kehrl J H , Thevenin C , Rieckmann P , Fauci A S 
Published: December 2022

Abstract
Transforming growth factor-beta (TGF-beta) inhibits B cell Ig secretion and reduces B cell membrane Ig expression. The addition of TGF-beta to human B lymphocyte cultures stimulated with Staphylococcus aureus Cowan strain I and IL-2 completely inhibited B cell Ig secretion (greater than 90%) and decreased B cell surface IgM, IgD, kappa L chain, and lambda L chain expression. In contrast, TGF-beta had only minimal effects on two other B cell membrane proteins, HLA-DR and CD20. Internal labeling with [35S]methionine and immunoprecipitation with anti-IgM, anti-kappa, and anti-lambda antibodies revealed a striking reduction in kappa L chain in the presence of TGF-beta. A less pronounced reduction in lambda L chain and microH chain was also noted. Northern blot analysis of RNA purified from B cells treated with TGF-beta for varying time intervals revealed a significant decrease in steady state kappa and lambda L chain mRNA levels. Furthermore, a significant decrease in the switch from the membrane forms of mu and gamma to their respective secreted forms was noted in the presence of TGF-beta. Nuclear run-on experiments demonstrated decreased transcription of kappa L chain. The effects of TGF-beta on two transcriptional regulatory factors, Oct-2 and nuclear factor (NF) kappa B, known to be important in Ig gene transcription were examined. Oct-2 mRNA levels and both Oct-2 and NF-kappa B proteins in nuclear extracts were not altered by treatment with TGF-beta. In contrast, levels of the transcriptional factor AP-1, which is not known to be important in B cell Ig production, were reduced by TGF-beta. These findings demonstrate that TGF-beta decreases B lymphocyte Ig secretion by inhibiting the synthesis of Ig mRNA and inhibiting the switch from the membrane form to the secreted forms of mu and gamma mRNA. The mechanism by which TGF-beta inhibits Ig chain synthesis is unclear although it does not involve inhibition of the binding of NF-kappa B or Oct-2 to their respective target sequences.
CD59 functions as a signal-transducing molecule for human T cell activation.
Authors: Korty P E , Brando C , Shevach E M 
Published: December 2022

Abstract
The CD59 Ag is a 20-kDa protein that is widely expressed on most leukocytes and RBC, is coupled to the membrane by a phosphatidylinositol-glycan anchoring structure, plays a role in cell interaction between monocytes and T cells, and also functions as an inhibitor of cytolysis by the terminal C components C5b-9. Because this molecule is structurally related to the murine Ly-6 family of Ag, we have investigated whether anti-CD59 mAb might be capable of activating human T lymphocytes in a manner similar to that described for antibodies to the murine Ly-6 Ag. In the presence of the appropriate co-stimulators, mAb to one of the two epitopes on CD59 were capable of inducing both a rise in intracytoplasmic free Ca2+, inositol phosphate production, IL-2 production, and T cell proliferation. Anti-CD59-induced inositol phosphate turnover and IL-2 production were dependent on co-expression of the CD3/TCR complex. CD59-loss mutants of the Jurkat cell line were completely responsive to stimulation by anti-CD3 thereby demonstrating that CD59 does not play a role as a signal transducer downstream from the TCR. Taken together, these results demonstrate that the CD59 Ag can play multiple distinct roles in the regulation of the immune response.
IL-1 alpha induces granulocyte-macrophage colony-stimulating factor gene expression in murine B lymphocyte cell lines via mRNA stabilization.
Authors: Akahane K , Cohen R B , Bickel M , Pluznik D H 
Published: December 2022

Abstract
IL-1 has been shown to induce granulocyte-macrophage (GM)-CSF production in several cell types including T lymphocytes, fibroblasts, and endothelial cells. We have previously demonstrated that bacterial LPS activates expression of the GM-CSF gene in murine B lymphocytes. Inasmuch as LPS is also an inducer of IL-1, we asked whether IL-1 could itself induce GM-CSF gene expression in B lymphocytes. The GM-CSF-dependent PT-18 cell line was used to detect GM-CSF biologic activity and a semi-quantitative polymerase chain reaction assay was developed to detect and measure GM-CSF mRNA. IL-1 alpha stimulated GM-CSF production by the murine B cell lines M12.4.1 and TH2.2 but not by the M12 line in a dose- and time-dependent fashion. GM-CSF mRNA expression in IL-1 alpha-treated M12.4.1 cells also increased in a dose- and time-dependent fashion. Nuclear run-on transcription assays revealed constitutive transcription of the GM-CSF gene in untreated M12.4.1 cells that did not change after IL-1 alpha treatment. Actinomycin D chase experiments indicated that IL-1 alpha increased GM-CSF mRNA stability in the M12.4.1 cells. These findings indicate that IL-1 alpha induces GM-CSF gene expression in murine B cell lines and that this event is posttranscriptionally controlled mainly at the level of mRNA stabilization.
A monoclonal antiidiotypic antibody with rheumatoid factor activity defines a cross-reactive idiotope on murine anticollagen antibodies.
Authors: Nordling C , Holmdahl R , Klareskog L 
Published: December 2022

Abstract
A syngeneic antiidiotypic mAb, C1C3, was characterized as to its binding to monoclonal anti-collagen II (-CII) auto-antibodies reactive with different epitopes of the native CII molecule. Both by direct binding and by inhibition ELISA studies, the anti-idiotypic antibody was shown to react with a cross-reactive idiotope present on Fab fragments of most, but not all, tested anti-CII mAb, whereas the binding to Fab fragments from normal mouse IgG was low. As previously described, C1C3 bound to isolated Fc fragments from normal mouse IgG. The binding to intact normal mouse IgG was, however, weak, and only isolated Fc-gamma fragments, not intact IgG, competed efficiently with Fab fragments of anti-CII antibodies for binding to the antiidiotypic antibody. The antibody was shown to self-associate, i.e., to behave similarly to certain IgG rheumatoid factors obtained from patients with rheumatoid arthritis. The presented data indicate that the described anti-anti-CII mAb may be representative of antibodies involved in the physiologic regulation of autoimmunity to CII and, consequently, may be used as a tool for further studies on idiotypic regulation in CII-induced arthritis.