bluuebunny/crossref_metadata_2025_split huggingface dataset:
An immunochemical study of the combining site specificities of C57BL/6J monoclonal antibodies to alpha (1----6)-linked dextran B512.
Authors: Newman B A , Kabat E A 
Published: December 2022

Abstract
This is the first report of an immunochemical study of the combining site specificities of a set of monoclonal antibodies to dextran B512 from C57BL/6J mice. The results confirm previous observations on antidextran combining sites and reveal specificities not seen earlier extending the observed repertoire of antibody combining sites to the single alpha (1----6)-linked glucosyl antigenic determinant. Eight C57BL/6J anti-dextran B512 hybridomas, four IgM,kappa and four IgA,kappa, were produced by PEG fusion of immune spleen cells with the nonproducer myeloma cell line P3X63Ag8 6.5.3. Antibody combining site specificities were determined by quantitative precipitin assays with 14 dextrans. Native dextrans with high percentages of linear alpha (1----6)-linked glucoses, similar to the immunogen B512, were the best precipitinogens; dextrans with alternating alpha (1----3), alpha (1----6) linkages, and highly branched dextrans were less effective. All antibodies precipitated with a synthetic, unbranched alpha (1----6)-linked dextran, suggesting their combining sites were "groove-like" and directed toward internal sequences of alpha (1----6)-linked residues, rather than "cavity-like" and directed toward a nonreducing terminal glucose. Two of the IgA hybridomas gave biphasic precipitin curves with dextran B512; this was shown to be due to differences in the precipitability of IgA monomers and polymers. Differences were observed in the reactivities of several dextrans considered previously to be structurally similar, and a newly proposed structural model of dextran B1299S was assessed. Quantitative precipitin inhibition studies with alpha (1----6)-linked isomaltosyl (IM) oligosaccharides, IM2 to IM9, showed that maximum inhibition was reached with IM6 or IM7, consistent with earlier estimates of the upper limit for the sizes of anti-B512 combining sites. Two IgM hybridomas showed a unique pattern, with inhibition being obtained only with IM5 or larger IM oligosaccharides. Association constants of the antidextrans for dextran B512 and for IM7, determined by affinity gel electrophoresis, ranged from 10(2) to 10(4) ml/g, comparable to earlier findings with antidextrans and other anticarbohydrate antibodies.
The association between murine beta 2-microglobulin and HLA class I heavy chains results in serologically detectable conformational changes of both chains.
Authors: Ferrier P , Layet C , Caillol D H , Jordan B R , Lemonnier F A 
Published: December 2022

Abstract
HLA-A3-, HLA-B7-, and HLA-CW3-transfected L cells, maintained in medium supplemented with murine serum so as to ensure that the human heavy chains were associated with murine beta 2-microglobulin, were subjected to a systematic serologic analysis for an evaluation of the structural consequences of such an heterologous association. The hybrid molecules exhibited alterations of their serologic reactivities that suggest the occurrence of structural modifications of both light and heavy chains. Thus, reactivity of HLA-A3-, HLA-B7-, and HLA-Cw3-transfected L cells with a monoclonal antibody (B1.1G6) directed at a human beta 2-microglobulin specific antigenic determinant was observed; this implies structural modifications of murine beta 2-microglobulin after its association with HLA class I heavy chains. Conversely, a profound reduction of the reactivity of the same transfectants with a monoclonal antibody (W6/32) directed at a monomorphic heavy chain related epitope was observed. The W6/32 reactivity was restored after replacement of the murine by the human light chain, indicating that the conformation adopted by the HLA class I heavy chain depends on the origin of the beta 2-microglobulin associated. Therefore it appears that the complex interactions that develop between the extracellular domains (including the one formed by the light chain) markedly influence the overall structure and the antigenic properties of HLA class I molecules.
Tumor-promoting phorbol esters induce rapid internalization of the C3b receptor via a cytoskeleton-dependent mechanism.
Authors: O'Shea J J , Brown E J , Gaither T A , Takahashi T , Frank M M 
Published: December 2022

Abstract
Plasma membrane expression as well as phagocytic capability of the C3b receptor (CR1) are under regulatory control. Phorbol esters are one class of agents which have been shown to influence both of these events. In this study, by using radiolabeled Fab fragments of a monoclonal anti-CR1 antibody to tag the receptor and acid elution of surface-bound Fab, we showed that both phorbol myristate acetate and phorbol dibutyrate induced internalization of the C3b receptor; this occurred in a dose- and time-dependent manner in the absence of occupancy of the receptor by ligand. This was shown to occur in neutrophils, monocytes, and macrophages. We also showed that phorbol esters enhanced CR1-dependent phagocytosis despite the presence of two-thirds fewer receptors present on the plasma membrane. However, fibronectin, another agent that influences phagocytosis, had no effect on receptor internalization. Phorbol ester internalization was temperature-dependent and was inhibitable by cytochalasins B and D. Inhibition of internalization was reversible when cytochalasin B was removed. Phorbol esters also induced increased detergent insolubility of CR1 with kinetics similar to those of receptor internalization. It is possible that association of CR1 with the cytoskeleton is important to the process of "activation" of CR1 in phagocytosis.
Calcium ionophore A23187 calcium-dependent cytolytic degranulation in human eosinophils.
Authors: Fukuda T , Ackerman S J , Reed C E , Peters M S , Dunnette S L , Gleich G J 
Published: December 2022

Abstract
The divalent cation ionophore A23187 is frequently used for studies of eosinophil degranulation. Nonetheless, the mechanism whereby A23187 induces degranulation in human eosinophils is still unclear. In the present experiments, A23187 caused human eosinophils to release a granule protein, eosinophil-derived neurotoxin (EDN) and a membrane-associated protein, Charcot-Leyden crystal (CLC) protein in a calcium and a concentration-dependent manner. However, A23187 at a concentration (1 microgram/ml) that caused 15% EDN release and 30% CLC protein release also produced release of the cytoplasmic enzyme lactic dehydrogenase (LDH) and loss of cell viability, both of which were calcium dependent. CLC protein release preceded EDN release and was detectable even at 15 min after the addition of 1 microgram/ml A23187, whereas EDN release occurred after a lag period of 30 min, and coincided with LDH release. At 1 microgram/ml A23187, neither the release of LDH nor the loss of viability occurred with purified neutrophils obtained in the same blood sample as a by-product of eosinophil purification. Electron microscopic examination demonstrated that exposure to A23187 for 15 min resulted in an increase and elongation of microridges on the cell surface, and exposure for 45 min caused cell disruption followed by extrusion of membrane-bound granules through breaks in the plasma membrane. Only once was granule exocytosis observed. These results indicate that A23187 treatment of eosinophils causes an initial release of membrane-associated CLC protein by a noncytolytic mechanism, and causes degranulation as a result of eosinophil lysis.
Theiler's murine encephalomyelitis virus (TMEV)-induced demyelinating disease in mice is influenced by the H-2D region: correlation with TEMV-specific delayed-type hypersensitivity.
Authors: Clatch R J , Melvold R W , Miller S D , Lipton H L 
Published: December 2022

Abstract
Intracranial inoculation of Theiler's murine encephalomyelitis virus (TMEV) leads to the development of a chronic demyelinating disorder in certain mouse strains. Development of this disease is controlled by at least two unlinked genes, one of which is within or linked to the H-2 complex. In the present study, we attempted to map the relevant H-2 loci involved in susceptibility to TMEV-induced demyelination using crosses between SJL and several congenic H-2 recombinant mouse strains bearing different combinations of MHC genes from the susceptible H-2s and resistant H-2b haplotypes all on the C57BL/10 strain background. The data suggest that the D region of the H-2 complex strongly influences development of the demyelinating disease because increased susceptibility correlates well with homozygosity for H-2s alleles in the D region, but not in K or I-A. In addition, we also attempted to correlate certain immune and nonimmune pathophysiologic parameters with the development of clinical disease. Specifically, central nervous system TMEV titers and TMEV-specific humoral and cellular [delayed-type hypersensitivity (DTH) and T cell proliferative (Tprlf)] responses were examined. The data show that TMEV-induced demyelinating disease did not correlate with either CNS TMEV titers or TMEV-specific humoral or Tprlf responses but did correlate closely with the presence of high levels of TMEV-specific DTH. Collectively, our findings demonstrating a strong correlation between disease incidence, the presence of particular H-2D region genotypes, and high levels of TMEV-specific DTH in susceptible strains (as well as previous findings showing predominant mononuclear cell infiltrates in CNS demyelinating lesions) support the hypothesis that the disease is immune mediated rather than a result of direct cytolytic effects of virus infection.
Activation of the gamma 1 gene by lipopolysaccharide and T cell-derived lymphokines containing a B cell differentiation factor for IgG1 (BCDF gamma).
Authors: Yuan D , Weiss E A , Layton J E , Krammer P H , Vitetta E S 
Published: December 2022

Abstract
By using both pulse labeling of nascent RNA chains and lactoperoxidase-catalyzed cell surface radioiodination, we examined both the de novo synthesis of mRNA for gamma-chains and the expression of membrane IgG (mIgG) on cells which had been stimulated with LPS plus a T cell supernatant (SN) containing a B cell differentiation factor for IgG1 (BCDF gamma). Our results show that neither nascent mRNA for gamma 1 chains nor mIgG1 can be detected in B lymphocytes until they have been stimulated by both LPS and BCDF gamma-containing T cell SN, and suggest that cell surface expression and secretion of IgG1 are coordinately controlled.
The serologic response to Meth A sarcoma vaccines after cyclophosphamide treatment is additionally increased by various adjuvants.
Authors: Livingston P O , Jones M , Deleo A B , Oettgen H F , Old L J 
Published: December 2022

Abstract
We have shown previously that the serologic response of BALB/c mice to immunization with BALB/c sarcoma Meth A cells can be more effectively augmented by pretreatment with cyclophosphamide (Cy) than by the use of adjuvants. The serologic response was directed against a highly restricted cell surface antigen, closely related to or identical with the unique transplantation antigen characteristic for this tumor. In this paper, we report the results of our attempts to obtain additional augmentation by using Cy and adjuvants together. For these studies, the optimal Cy dose, interval between Cy and vaccine administration, and vaccine cell number were determined. Mice were injected with Cy 25 mg/kg i.p., and 3 days later, with viable irradiated (10,000 rad) Meth A cells subcutaneously, under conditions in which only few mice produced antibody. Sera were tested for antibody with reactivity against Meth A by complement dependent cytotoxicity (CDCX), which predominantly detects IgM, and by the protein A (PA) and anti-IgG assays, which detect IgG. Of the various adjuvants tested, only monophosphoryl lipid A (MPLA) and CP20,961 resulted in significantly increased titers of reactivity in both the CDCX and PA assays over that obtained when using Cy alone. Although the mean titers observed with CDCX ranged between 1/160 and 1/320, no titer above 1/40 was observed with the PA assay. The specificity of the CDCX reactivity detected by the assay for the Meth A antigen was ascertained by absorption analysis of selected sera by using a panel of BALB/c spleen and tumor cell lines grown in vitro or in vivo. PA titers were too low to permit absorption analysis, and the titers obtained in the anti-IgG assay were lower still. Attempts to augment the anti-Meth A IgG response or to convert the IgM response to IgG were unsuccessful. The combined approach described here (i.e., vaccination with irradiated syngeneic tumor cells plus MPLA in Cy-pretreated mice) was also shown to be effective in augmenting the serologic response against two additional murine leukemia virus-negative sarcomas that are known to be less immunogenic, CMS4 and CMS5. It appears, therefore, that this combined approach may be applicable to stimulating serologic responses against a variety of tumor cell surface antigens.
The role of suppressor T cells in BCNU-mediated rejection of a syngeneic tumor.
Authors: Nagarkatti M , Kaplan A M 
Published: December 2022

Abstract
The present investigation was initiated to determine the mechanism by which 1,3-bis(2-chloro-ethyl)-1-nitrosourea (BCNU) treatment of tumor-bearing mice results in a high percentage of surviving mice which are resistant to subsequent homologous tumor challenge. Spleen cells from C57BL/6 mice bearing the syngeneic LSA ascites tumor failed to demonstrate significant tumor-specific cytotoxic T lymphocyte (CTL) activity when stimulated in vitro with irradiated tumor cells. This lack of CTL activity correlated with the presence and high activity of two types of CTL-regulatory suppressor T cells (Ts), tumor-specific Thy-1+, Lyt-1-2+ and tumor-nonspecific Thy-1+, Lyt-1+2+ cells, as demonstrated by a double-positive selection technique. In contrast, spleen cells from BCNU-treated tumor-bearing mice generated high tumor-specific CTL activity when stimulated in vitro with irradiated tumor cells. This CTL activity correlated with the lack of demonstrable tumor-specific Ts and greatly diminished tumor-nonspecific Ts activity. The tumor-specific helper activity of Thy-1+, Lyt-1+,2- cells was found to be similar in both BCNU-treated and untreated tumor-bearing mice. BCNU-treated mice that survived a primary LSA tumor challenge (referred to as BCNU-cured mice) resisted subsequent challenge with the homologous (LSA) but not with a heterologous syngeneic tumor (EL-4). However, rejection of a secondary challenge with LSA tumor by BCNU-cured mice was inhibited by adoptive transfer of spleen cells from either normal mice or mice bearing LSA tumors. Furthermore, LSA tumor cells that failed to evoke tumor-specific CTL activity in normal mice could induce high CTL activity in BCNU-cured mice. The present study suggests that, in addition to its direct tumoricidal activity, BCNU inhibits the induction of tumor-specific Ts, thereby explaining why a high percentage of mice survive a primary syngeneic tumor challenge after treatment with BCNU, and also resist subsequent rechallenge with the homologous tumor.
Human immune response to multiple injections of murine monoclonal IgG.
Authors: Shawler D L , Bartholomew R M , Smith L M , Dillman R O 
Published: December 2022

Abstract
Murine monoclonal antibody infusions in humans should induce a human anti-mouse immunoglobulin (mIgG) immune response, especially if multiple infusions over an extended period of time are necessary for therapeutic efficacy. We have administered multiple infusions of the murine monoclonal antibody T101 to patients with cutaneous T cell lymphoma (CTCL) or chronic lymphocytic leukemia (CLL). Five of 10 CTCL patients, compared with zero of six CLL patients, developed antibodies to mIgG. In those CTCL patients who did not demonstrate anti-mIgG antibodies, we were unable to correlate the lack of response to any of a large number of clinical parameters. Anti-mIgG antibodies were of both the mu and gamma isotypes and were detectable 14 days after the first infusion. Multiple infusions were associated with elevated titers. The anti-idiotypic portion of the anti-mIgG titer steadily increased with each infusion until eventually, in one patient receiving eight weekly infusions, well over one-half the serum anti-mIgG recognized only T101 and not four other murine IgG2AK antibodies tested. To increase our confidence in these findings, four separate assay systems were used to make these determinations. The identification of anti-idiotype antibodies as the dominant species of the immune response to multiple infusions of murine monoclonal antibody has major implications for future work with monoclonal antibodies. Although it has been suggested that human monoclonal antibodies would obviate an immune response, our work implies that such antibodies might still induce anti-idiotype antibodies if multiple infusions are administered.
Tolerance induction in antigen-specific helper T cell clones and lines in vitro.
Authors: Levich J D , Parks D E , Weigle W O 
Published: December 2022

Abstract
The induction of T cell tolerance in vitro was investigated by using HGG-specific murine helper T cell (Th) clones and cell lines. It was found that exposure of Th to monomeric HGG (tolerogen) for 18 hr rendered the Th unable to reconstitute the PFC response of HGG-primed B cells. The tolerant state was not a result of Th cell death, as up to 100% of Th could be recovered after exposure to the monomer, and in addition, the recovered cells proliferated in response to IL2. B cells were shown not to be significantly affected by the presence of monomeric HGG in amounts calculated to be carried over from the tolerization cultures into the assay cultures. Consequently, it was concluded that interaction between Th and monomeric HGG induced unresponsiveness at the T cell level. A comparison of the tolerogenic potential of monomeric, soluble, and aggregated HGG revealed that only the monomer could induce tolerance in Th. Monomeric HGG was also shown to induce tolerance in an antigen-specific manner. Th reactive to HGG could be tolerized by monomeric HGG, but not Th reactive to FGG or OVA. Helper function of Th was also shown to be antigen specific in that HGG-reactive Th helped only HGG-primed B cells. Certain HGG-specific Th clones were found to be refractory to tolerization with monomeric HGG, whereas other clones derived from the same uncloned cell line were tolerizable.
Genetic control of the murine immune response to cholera toxin.
Authors: Elson C O , Ealding W 
Published: December 2022

Abstract
This study was undertaken to determine whether previously noted differences in the immune response of inbred strains of mice to cholera toxin (CT) might be under immune response gene control. A series of inbred, congenic, and intra-H-2I region recombinant mouse strains were tested for responsiveness to CT after i.p. immunization with 0.1 micrograms CT in alum. Samples of plasma were collected at intervals before and after priming and boosting. IgG and IgA anti-CT were measured by ELISA. In three different sets of congenic strains, the level of IgG anti-CT clearly depended on the H-2 haplotype of the strain rather than on any background or Igh genes. Strains with the H-2b and H-2q haplotypes were high responders, and strains with the H-2k, H-2s and H-2d haplotypes were low responders. Within the H-2 complex, the IgG anti-CT response was mapped to the I-A subregion with the use of congenic intra-H-2I region recombinant strains. In contrast to these results with IgG anti-CT, plasma IgA anti-CT levels were uniformly low and indeterminate. We conclude that the murine IgG anti-CT response is controlled by a locus within the I-A subregion of H-2--a remarkable finding, considering the known abilities of this toxin to bind to and to directly stimulate lymphocytes.
Information transfer between T cell subsets is directed by I-J+ antigen nonspecific molecules.
Authors: Flood P M , Chue B , Whitaker R B 
Published: December 2022

Abstract
T cell antigen-specific suppressor factors (TsF) consist of two distinct polypeptide chains: one that binds antigen (ABM) and one that bears I-J region markers (I-J+ chain). We studied the functional role of these two molecules in delivering the biologic message of suppression to its appropriate target cell. Two different biologically active TsF were used in these studies: TsiF, a T suppressor-inducer factor consisting of an ABM secreted by Ly-1 T cells (Ti-ABM) and an I-J+ subfactor secreted by Ly-1 T cells (I-Ji), which initiates the suppressor circuit by inducing an Ly-1,2 T cell; and TseF, a T suppressor-effector factor consisting of an ABM secreted by Ly-2 T cells (Te-ABM) and an I-J+ subfactor secreted by Ly-1 T cells (I-Je), which delivers the biologic message of suppression to the T helper (TH) cell. In both TsF, the ABM and I-J+ chain are noncovalently associated and can be easily separated. Both molecules must be present, however, for biologic activity of the TsF to be manifest. We studied the role of each chain in delivering these biologically active messages by constructing "hybrid" factors made from mixing the ABM from TsiF with I-J+ chains from either TsiF or TseF and determined which of these chains could reconstitute functional TsiF activity. Likewise, we mixed the AMB from TseF with I-J+ chains of TsiF or TseF to determine which I-J+ chain could reconstitute TseF activity. We found that I-J+ chain from TsiF (I-Ji) can reconstitute ABM from TsiF to form a functional TsiF capable of inducing suppression but cannot reconstitute ABM from TseF to form a functional TsiF capable of suppressing the activity of TH cells. Likewise, the addition of I-J+ chain from TseF to ABM from TseF can reconstitute its ability to suppress TH responses, but I-J+ chain from TsiF plus ABM from TseF has no effect on these TH cell responses. We did find, however, that this hybrid TsF composed of the ABM from TseF and the I-J+ chain from TsiF is capable of suppressing the Ly-1,2 Ttrans cell, the cell normally induced by the ABM + I-J+ suppressor inducer complex from T suppressor-inducer cells (TsiF).(ABSTRACT TRUNCATED AT 400 WORDS)
Isolation and characterization of novel suppressor T cell clones from murine fetal thymus.
Authors: Teh H S , Ho M , McMaster W R 
Published: December 2022

Abstract
Murine fetal thymus from C57BL/6J (B6) and DBA/2J contains a cell population that suppresses CTL responses to alloantigens. This suppressor cell population was found to exist in high frequency in murine fetal thymus at the 14th day of gestation. The activity of this cell in the thymus declined rapidly with increasing time of gestation, and suppressor activity in the thymus was undetectable by the time of birth. On the other hand, suppressor activity could be detected in organ cultures of 14-day fetal thymus even after the organs were cultured for 14 or 21 days. Fetal thymocytes from B6 or DBA/2J mice were grown as long-term lines in interleukin 2 (IL 2)-containing medium. Clones of suppressor cells were derived from long-term cultures by micromanipulation. The clones had an average doubling time of 13 to 16 hr and were dependent on IL 2 for growth. The clones were 10- to 100-fold more efficient in suppressing CTL responses to alloantigens than day 15 fetal thymocytes. Analyses of cell surface molecules with the use of monoclonal antibodies and conventional anti-H-2 sera by radioactive binding assays showed that cloned suppressor cells from B6 fetal thymus were Thy-1 and Lyt-2+, and expressed little or no L3T4, Lyt-1, H-2K, H-2D, and class II molecules. The suppressor clones lacked the cytolytic activity of conventional CTL and also served as very poor target cells in CTL-mediated cytolysis. The suppressor function of the cloned cells was radiation-resistant, and this suppression could not be reversed by the addition of excess exogenous IL 2. The cloned cells suppressed CTL responses only when they were added within the first 48 hr of a 5-day culture period. Analyses of the antigen specificity of the suppressor cells showed that they suppressed CTL responses in a nonantigen-specific manner.