bluuebunny/crossref_metadata_2025_split huggingface dataset:
Immunofluorescent patterns of spectrin in lymphocyte cell lines.
Authors: Pauly J L , Bankert R B , Repasky E A 
Published: December 2022

Abstract
Spectrin, a membrane-associated cytoskeletal protein, has been observed in all of 45 lymphoid and myeloid cell lines examined. For these experiments, formalin-fixed cells from randomly selected lines propagated by using conventional tissue culture procedures were examined by immunofluorescence, using an antibody directed against chicken erythrocyte alpha-spectrin. Two distinct immunofluorescent patterns of spectrin distribution were identified. In most lines examined (16 mouse and 18 human lymphoid or myeloid lines), spectrin was symmetrically distributed near the submembranous region of the plasma membrane. In the remainder of the cell lines examined, a second pattern was observed; in these cultures, the cells contain a polar submembranous aggregate of spectrin with little staining at the rest of the plasma membrane. Long-term T lymphocyte cell lines in which greater than 60% of the cells expressed a polar submembranous aggregate of spectrin (PSA-S) include mouse cell lines EL-4, LBRM-33, CT-6X, NIXT, 22CM-37, and 7ON-2 and human lines JM and PEER. Other established cultures in which PSA-S were observed included the human macrophage-like line U-937 and gibbon T cell line MLA-144. Phorbol myristate acetate or mezerin caused a reversible alteration in the distribution of spectrin in these cell lines. These drugs, which increase membrane fluidity, caused a complete but temporary symmetrical redistribution of the spectrin aggregate. Our results indicate that the pattern of spectrin distribution, either aggregated or evenly dispersed, is a stable characteristic (but one that can be altered) in various cell lines, and that because similar variations in pattern have been noted in situ, it is likely that the pattern present in any given cell line reflects a characteristic associated with a particular stage of a cell's maturation. It is anticipated that these cell lines, positive and negative for the expression of natural polarity of spectrin distribution, will provide useful models for future studies to define further the role of spectrin in lymphocyte plasma membrane functions.
Characteristics of the expression of the murine soluble class I molecule (Q10).
Authors: Lew A M , Maloy W L , Coligan J E 
Published: December 2022

Abstract
Q10 is a class I molecule previously proven to be secreted rather than membrane bound. To measure the amount of Q10 in various mouse sera, a quantitative Western blot assay was developed. Q10 was the only class I molecule detectable in mouse sera. It occurs as a high m.w. complex of 200,000 to 300,000. The amount of Q10 in serum varies among different mouse strains and is controlled by a region telomeric to H-2S. Mice of the f haplotype do not express Q10, but all other mice examined (20 strains) with inbred or wild-derived H-2 haplotypes do. The H-2 haplotypes rank according to their levels of Q10 as follows: z, s greater than k, b greater than d, q greater than f; and the actual values range from to 60 micrograms/ml to undetectable levels in serum. In some strains the levels are higher in males than in females. The levels increase with age and decrease during pregnancy but not during lactation. There is a dramatic decrease after the injection of irritants or syngeneic tumor transplantation, but allostimulation has no effect on Q10 levels. The possible significance of this soluble class I molecule is discussed in the light of our findings.
Degradation of human anaphylatoxin C3a by rat peritoneal mast cells: a role for the secretory granule enzyme chymase and heparin proteoglycan.
Authors: Gervasoni J E , Conrad D H , Hugli T E , Schwartz L B , Ruddy S 
Published: December 2022

Abstract
Purified human C3a was iodinated (125I-C3a) and used to study the interaction of labeled peptide with rat peritoneal mast cells (RMC). Cellular binding of 125I-C3a occurred within 30 sec, followed by a rapid dissociation from the cell. Both the binding of 125I-C3a and the rate of dissociation from the cell were temperature dependent. At 0 degrees C, the binding of 125I-C3a was increased and the rate of dissociation reduced, as compared with 37 degrees C. Once 125I-C3a was exposed to RMC, it lost the ability to rebind to a second batch of RMC. Analysis of the supernatants by trichloroacetic acid (TCA) precipitation and electrophoresis in sodium dodecyl sulfate polyacrylamide gels (SDS PAGE) revealed a decrease in the fraction of 125I precipitable by TCA and the appearance of 125I-C3a cleavage fragments. Pretreatment of RMC with enzyme inhibitors specific for chymotrypsin, but not trypsin, abrogated the degradation of 125I-C3a. Treatment of RMC bearing 125I-C3a with bis (sulfosuccinimidyl) suberate (BS3) covalently cross-linked the 125I-C3a to chymase, the predominant enzyme found in the secretory granules. Antiserum directed against chymase precipitated 125I-C3a from extracts of RMC treated with BS3. Indirect immunofluorescence of RMC by using the IgG fraction of goat anti-rat chymase showed that chymase is present on the surface of unstimulated cells. Neither purified chymase nor heparin proteoglycan alone had any appreciable effect on 125I-C3a, but together they resulted in prompt degradation of the 125I-C3a. Immunoabsorption of RMC sonicates with specific antibody for chymase completely abrogated the ability of these sonicates to degrade 125I-C3a. The results indicate that 125I-C3a binds to RMC and is promptly degraded by chymase in the presence of heparin proteoglycan.
IL 2 restores memory B cell activation by antigen-specific T cell clone variants.
Authors: Ishihara T , Takahara S , Fathman C G 
Published: December 2022

Abstract
It has recently been demonstrated that there are at least two separate pathways by which a single keyhole limpet hemocyanin (KLH) reactive T cell clone can induce B cell differentiation. With the use of the high-dose antigen-driven system (10 micrograms/ml trinitrophenyl (TNP)-KLH), a KLH-specific T cell clone was able to induce a primary anti-TNP response in unprimed B cells. In the presence of aliquots of the same T cell clone, a low-dose of antigen (5 X 10(-2) micrograms/ml TNP-KLH) induced an immunoglobulin (Ig)G response in primed B cells. It has also been demonstrated that there are variant subclones of such KLH-specific helper T cell clones that are unable to provide antigen-specific help in the presence of low-dose antigen but maintain the high-dose antigen-driven helper response. This study was undertaken to investigate whether interleukin 2 (IL 2) had some activity in the low-dose, antigen-driven response induced by the T cell clone. With the use of a variant T cell clone (which lost low-dose, antigen-driven helper activity), it was demonstrated that IL 2 was capable of reconstituting the low-dose, antigen-driven helper activity. To investigate whether accessory cells were required in this system, we removed the adherent cell population from the primed spleen cells added to culture. Interestingly, removal of the G10-adherent cells eliminated the low-dose, antigen-driven response induced by IL 2. Additionally by add-back experiments, we were able to demonstrate that the necessary adherent cell population did not require major histocompatibility complex (MHC) restriction for reconstitution of the IL 2-dependent, low-dose, antigen-driven response. Furthermore, 1% concanavalin A (Con A) supernatant (Sn), but not interleukin 1 (IL 1), could replace this adherent cell function. These data suggest that in this system, IL 2 bypasses the MHC-restricted interaction between T cells and antigen-charged adherent cells; B cells can present antigen to cloned helper T cells efficiently for primary responses but need an added factor(s) to induce IgG production; and adherent cells are essential for IgG production in primed B cells, possibly through the release of soluble factor(s) included in Con A Sn.
Anti-idiotypic B cells are required for the induction of suppressor T cells.
Authors: Hausman P B , Sherr D H , Dorf M E 
Published: December 2022

Abstract
A nylon wool-adherent, B cell-enriched population is required during the in vitro induction of third order effector suppressor T cells (Ts3). This B cell population expresses IgM and IgD and is devoid of conventional T cell markers such as Thy-1, L3T4, and Lyt-1. Treatment of the B cell population with anti-NP antibodies expressing the NPb idiotype and complement specifically eliminated the ability to generate Ts cell activity, suggesting that the critical B cells expressed anti-idiotypic receptors. To independently verify the role of anti-idiotypic B cells in the generation of Ts cells, B cells were panned on antibody-coated plates. The results demonstrated that only NPb idiotype-binding B cells could induce effector suppressor cells from naive T cell populations. The combined data demonstrate the role of Ig network interactions in the generation of Ts cells.
Glycopeptides inhibit allospecific cytotoxic T lymphocyte recognition in an MHC-specific manner.
Authors: Pimlott N J , Miller R G 
Published: December 2022

Abstract
Attempts to block specific T cell recognition with soluble extracts have been uniformly unsuccessful. However, we found that glycopeptides prepared from three MHC-different tumor cell lines were able to inhibit binding of allospecific cytotoxic T lymphocytes (CTL) to an appropriate tumor cell or Con A blast target cell. Inhibition was only observed when the MHC of the cell providing the glycopeptide was the same as the MHC of the target cell being recognized. This result was obtained by using both fully allogeneic CTL and CTL generated between B10 congenic mice differing only at the MHC. This suggests that the inhibition depends on the MHC expressed by the target cell. Because we extensively pronase digested cell glycoproteins and then enriched for glycopeptides containing small amounts of peptide, we attribute the inhibition to the carbohydrate portion of the glycopeptide. Our observations suggest that CTL may, in part, recognize carbohydrate molecules on the target cell surface whose specific structure(s) is influenced or regulated by genes in or near the MHC. They also suggest that the T cell receptor complex has some lectin-like properties.
Phenotypic analysis of thymocytes that express homing receptors for peripheral lymph nodes.
Authors: Reichert R A , Weissman I L , Butcher E C 
Published: December 2022

Abstract
Thymocytes that express high levels of homing receptors for peripheral lymph nodes can be detected with the monoclonal antibody MEL-14. We have shown that in adult mice these rare MEL-14hi thymocytes a) are cortical in location and typically constitute 1 to 3% of the total thymocyte population, b) may be a major source of thymus emigrants, and c) contain a high frequency of precursors of alloreactive cytotoxic T lymphocytes. In this study we have analyzed the phenotype of the MEL-14hi thymocyte subset. Most normal adult MEL-14hi thymocytes are midsize and express the mature phenotype typical of thymus emigrants, medullary thymocytes, and peripheral T cells: they are predominantly PNAlo, H-2K+, Thy-1+, Ly-1hi, and either Lyt-2-/L3T4+ or Lyt-2+/L3T4-. These findings argue strongly for the presence of rare MEL-14hi immunocompetent cortical thymocytes that, aside from their homing receptor expression, are phenotypically indistinguishable from medullary thymocytes. However, a minority (20 to 30%) of MEL-14hi thymocytes are large and phenotypically nonmature: they express intermediate to high levels of PNA binding sites, and are H-2K- to H-2Klo, Thy-1hi, Ly-1+, and either Lyt-2+/L3T4+ or Lyt-2-/L3T4-. Through a technique that selectively labels outer cortical cells, phenotypically nonmature MEL-14hi thymocytes have been shown to be concentrated in the subcapsular blast region of the outer cortex. Although we have no direct evidence of a precursor-product relationship, we consider it likely that the phenotypically nonmature outer cortical MEL-14hi lymphoblasts give rise to phenotypically mature MEL-14hi cells located deeper in the cortex. These results are consistent with our previous proposal that MEL-14hi thymocytes are a major source of thymus emigrants, and indicate that expression of high levels of MEL-14-defined homing receptors may be closely linked to the intrathymic selection process.
Signals involved in T cell activation. II. Distinct roles of intact accessory cells, phorbol esters, and interleukin 1 in activation and cell cycle progression of resting T lymphocytes.
Authors: Davis L , Lipsky P E 
Published: December 2022

Abstract
The signals involved in the initiation of mitogen-induced activation of resting guinea pig T cells were examined. The combination of phytohemagglutinin (PHA) and 4 beta-phorbol 12-myristate 13-acetate (PMA) stimulated DNA synthesis by accessory cell (AC)-depleted T cells cultured at high density, but the use of low density cultures indicated that intact AC were absolutely necessary for PHA-stimulated T cell DNA synthesis even in the presence of PMA, interleukin 1 (IL 1), or interleukin 2 (IL 2). In contrast, AC-depleted T cells were able to respond to the combination of the calcium ionophore, ionomycin, and PMA regardless of the cell density at which they were cultured. Cell cycle analysis by acridine orange staining indicated that neither PHA nor ionomycin, in the absence of AC, activated resting T cells. PMA in the absence of all AC, supported cell cycle entry and progression to the DNA synthetic phase of the majority of ionomycin-stimulated T cells, but permitted only a small number of PHA-triggered T cells to enter the initial stage of the cell cycle (G1a) characterized by a modest increase in cellular RNA content. Although PMA permitted some PHA-stimulated T cells to enter the cell cycle, most required intact AC to enter G1, and all required intact AC to progress through G1 and synthesize maximal amounts of RNA. No PHA-stimulated cells reached the S phase without intact AC. In PHA-stimulated cultures containing intact AC, PMA increased the number of cells entering the cell cycle and increased the rate of their progress to the DNA synthetic phase. IL 1 also augmented PHA-stimulated AC-dependent T cell DNA synthesis in the presence or absence of PMA, but appeared to be most active during the later stage of the first cell cycle, augmenting the number of activated cells that entered the S phase of the cell cycle. These results support the conclusion that intact AC, IL 1, and a PMA-like signal play distinct roles in the progression of mitogen-stimulated T cells through the first round of the cell cycle.
Different subclass distribution of IgA-producing cells in human lymphoid organs and various secretory tissues.
Authors: Kett K , Brandtzaeg P , Radl J , Haaijman J J 
Published: December 2022

Abstract
A highly reproducible paired immunofluorescence staining method was used to map the relative distribution of IgA1- and IgA2-producing cells in peripheral lymphoid organs and various secretory tissues. Spleen, peripheral lymph nodes, and tonsils all contained a marked predominance (91 to 95%) of IgA1 immunocytes. However, striking variations were demonstrated among the secretory tissues with regard to the median proportion of IgA1-producing cells: nasal mucosa, 96%; lacrimal glands, 81%; major salivary glands, 66%; mammary glands, 63%; gastric and proximal small intestinal mucosa, 84 to 77%; ileum, 55%; and large bowel, 41%. Thus, IgA2 production is relatively enhanced mainly in the distal gut and in mammary and salivary glands, in that order.
Release of lymphokines after Epstein Barr virus infection in vitro. I. Sources of and kinetics of production of interferons and interleukins in normal humans.
Authors: Lotz M , Tsoukas C D , Fong S , Dinarello C A , Carson D A , Vaughan J H 
Published: December 2022

Abstract
Infection of human lymphocytes with Epstein Barr virus (EBV) activates the release of lymphokines. Previous experiments have emphasized the ability of interferon-gamma (IFN-gamma) to prevent EBV-induced B cell transformation. However, the factors that regulate IFN-gamma synthesis and release during in vitro EBV infection are controversial. In the present investigation we have systematically evaluated the kinetics of production, cellular origins, and accessory cell requirements for IFN-alpha and IFN-gamma and for IL 1 and IL 2, after EBV infection. Our data indicate that IFN-alpha is released entirely by natural killer (NK) cells and B cells, in the absence of accessory cells, independently of the other lymphokines and within 24 hr of infection. In contradistinction, IFN-gamma secretion is exclusively of T cell origin, is absolutely dependent on the prior elaboration of IL 1 and IL 2, and is maximal 8 days after EBV infection. IL 2 secretion by T cells peaks on day 5 and requires the earlier release of IL 1. Both NK cells and monocytes are a source of IL 1. Secretion of IL 2 and IFN-gamma occurs in the presence of either one of these cell types but not in the absence of both. Antibody against IL 1 blocks EBV-induced IL 2 and IFN-gamma generation, and antibody against IL 2 decreases production of IFN-gamma. Thus, the production of IFN-gamma, the lymphokine that prevents EBV-induced B cell transformation, is the final outcome of a cascade of lymphokine-mediated events that involve interactions between virus-infected B lymphocytes that serve as antigen-presenting cells, NK cells and monocytes as sources of IL 1, and T lymphoblasts. Dysfunctions of any or all of these cell types would be expected to impair the regulation of EBV transformation.
Normal human neutrophils are a source of a specific interleukin 1 inhibitor.
Authors: Tiku K , Tiku M L , Liu S , Skosey J L 
Published: December 2022

Abstract
In the course of our study on neutrophil production of an interleukin 1 (IL-1)-like factor, we found that the addition of polymorphonuclear neutrophils (PMN) to monocytes cultured in the presence of zymosan resulted in decreased IL 1 activity of the resultant supernatant, suggesting that PMN may contain an inhibitor of IL 1. The objective of this investigation was to study this IL 1 inhibitor which normal human PMN contain. The inhibitor is constitutively present in the PMN because 0 hr PMN lysates and unstimulated PMN supernatants also show inhibitory activity. The PMN inhibitor inhibits IL 1 (crude and partially purified) in a dose-response manner and does not affect basal [3H]thymidine incorporation in the presence or absence of PHA-P. The PMN inhibitor does not have any effect on interleukin 2 (IL 2)-induced proliferation of the IL 2-dependent CTLL cells. The inhibitor can be generated in the absence of serum and is not produced as a result of proteolytic activity from PMN enzymes. The inhibitor is heat-labile and is most stable at neutral pH. Gel filtration studies on Sephadex G-200 indicate that the inhibitor is heterogeneous in size. Two inhibitory peaks, at 45,000 to 70,000 m.w. and at greater than 160,000 m.w., were observed. When zymosan-stimulated PMN supernatant was chromatographed, there was separation of inhibitory factor from a 17,000 m.w. proliferating factor. Presence of this PMN inhibitor may be important in negative regulation of IL 1.
A novel idiotopic determinant on phosphorylcholine-binding immunoglobulins restricted to isotype and allotype.
Authors: Cronkhite R I , Cerny J 
Published: December 2022

Abstract
A shared idiotopic (Id) determinant, designated B24-50, was detected on phosphorylcholine (PC)-binding myeloma proteins by using a monoclonal antibody. Analysis of immune sera from inbred and congenic strains of mice revealed the presence of this Id determinant on a very small proportion of the PC-binding immunoglobulins (Ig). Hybridoma and myeloma proteins of various classes were analyzed for B24-50 expression, and a clear association of B24-50 with IgA was demonstrated. The Id was found on two distinct idiotypic families, (TEPC15 and McPC603), which share a similar heavy chain but have different light chains; however, isolated heavy chains did not express B24-50. The Id did not require the absolute association of the TEPC15 light chain V kappa 22 with the TEPC15 heavy chain but appeared dependent upon the interaction of the light chain with the TEPC15 heavy chain via quaternary interactions and/or shared amino acid residues of V kappa 8 (M603) and V kappa 22. Furthermore, B24-50 was not found on IgA of strains with the Ighb allotype. Thus B24-50 is a novel isotype-restricted determinant found on two Id families and is influenced by the Igh allotype.
Xid and normal mice express a light chain-associated cross-reactive idiotype in response to (T,G)-A--L and (T,G)-A--L-mBSA.
Authors: Busto P , Giorgetti C A , Gawoski J , Press J L 
Published: December 2022

Abstract
Rabbit anti-idiotypic (Id) antibodies were prepared against purified ascites anti-(T,G)-A--L antibodies (TGB5) that had been absorbed to remove A--L-specific antibodies and were specific for (T,G)-side chain determinants. Purified rabbit anti-TGB5 Id antibodies detected an allotype-independent, light chain-associated cross-reactive Id expressed by the majority of individual mice immunized with (T,G)-A--L, (T,G)-A--L coupled to methylated bovine serum albumin (mBSA), or the linear terpolymer GAT. Primary and secondary monoclonal hybridoma protein (HP) antibodies from X/Xxid heterozygous (wild-type) mice immunized with (T,G)-A--L and/or (T,G)-A--L-mBSA were analyzed for isotypy and were grouped into eight antibody fine specificity sets defined by the patterns of direct binding to the antigens (T,G)-A--L, (Phe,G)-A--L, (T,G)-Pro--L, GT, and A--L. Analysis of these primary and secondary HP for TGB5 idiotypy showed a preferential expression of the TGB5 Id among GT+-binding HP (antibody fine specificity sets 1 through 3). All of the primary GT+-binding HP and the majority of secondary GT+-binding HP (sets 1 through 3) were TGB5 Id+. Most but not all of the TGB5 Id+ HP bound GAT. Of the side-chain-specific HP (sets 1 through 7), 78% of primary HP vs 49% of secondary HP bound GT. By these criteria, the primary HP response appears more restricted than the secondary HP response, consistent with the idea that Id diversification and antibody heterogeneity are regulated and selected events occurring during memory B cell generation. Although xid mice produce less antibody than wild-type mice to (T,G)-A--L, the TGB5 Id was produced early in the primary response by both xid and wild-type mice immunized with (T,G)-A--L or (T,G)-A--L-mBSA, and was maintained as a detectable Id in equivalent amounts in their secondary serum antibody responses. These results support the idea that distinct B cell subsets, including the xid B cell subset, share the same immunoglobulin gene repertoire.
The kinetics of clearance of human antibody/dsDNA immune complexes from rabbit circulation. Effects of dsDNA size, rheumatoid factor, and reduction and alkylation of the antibodies.
Authors: Taylor R P , Kujala G , Edberg J C , Foreman P , Davis J S , Wright E 
Published: December 2022

Abstract
We have conducted in vivo investigations of the rate of clearance of prepared antibody/dsDNA immune complexes from the circulation of rabbits and have correlated the results with some in vitro immunologic properties of the complexes. Those complexes that fix complement most efficiently in vitro (as manifested by their complement-mediated binding to human red blood cells or rabbit platelets) are cleared most rapidly. Factors that decrease this binding such as reduction and alkylation of the antibodies or the use of dsDNA of a lower m.w. also tend to prolong the circulation times for the complexes. This study provides additional evidence in support of a complement-mediated platelet immune complex clearance mechanism in non-primates that parallels the erythrocyte immune complex clearance mechanism in primates first described by He bert. Finally, the implications of our findings with respect to the importance of dsDNA size in the pathogenesis of systemic lupus erythematosus are discussed.