bluuebunny/crossref_metadata_2025 huggingface dataset:
Capacity of B cells to function as stimulators of a primary mixed leukocyte reaction.
Authors: Krieger J I , Chesnut R W , Grey H M
Published: December 2022

The capacity of B cells to serve as stimulator cells for a primary mixed leukocyte reaction (MLR) was evaluated. Percoll-fractionated B cells were stimulated with lipopolysaccharide and dextran sulfate (L/D) or a B cell stimulatory factor (BSF-1)-containing culture supernatant, and then were fixed before being used as stimulator cells to more precisely define the state of activation associated with MLR stimulatory capacity. It was found that unstimulated B cells or B cells stimulated for 1 day with L/D or BSF-1 were incapable of initiating a primary MLR, whereas B cells incubated for 3 days in L/D were potent stimulators. The differential activity of 1 day L/D- and BSF-1-activated B cells compared with 3 day L/D-activated B cells was not related to the amount of the relevant MHC class I or class II alloantigens on these cell populations, because all three groups had large increments in MHC class II expression in the following order: BSF-1 greater than 3 day L/D greater than 1 day L/D, and had little difference in MHC class I expression. Also, all three populations were capable of stimulating both MHC class I- and class II-specific T cell hybrids. It was concluded that the capacity of 3 day L/D-activated cells to stimulate a primary MLR was due to the elaboration of necessary co-stimulator molecules. We evaluated whether interleukin 1 (IL 1) was the co-stimulator involved. That this was not the case was indicated by two findings. First, 3 day-activated L/D cells failed to express IL 1 activity as measured by a highly sensitive IL 1 assay that utilizes the T cell line D10.G4.1. Second, recombinant IL 1 added to MLR cultures containing 1 day L/D- or BSF-1 activated B cells failed to function as a co-stimulator. In contrast, the phorbol ester PMA was a potent co-stimulator in this system. We conclude from these experiments that appropriately activated B cells can function as stimulators of a primary MLR, and that they elaborate critical co-stimulator molecules, distinct from IL 1, that enable them to function in this regard.
Selective in vitro inhibition of an antibody response to purified acetylcholine receptor by using anti-idiotypic antibodies coupled to the A chain of ricin.
Authors: DeShambo R M , Krolick K A
Published: December 2022

In vitro antibody responses by rat lymph node cells against purified acetylcholine receptor (AChR) were shown to be inhibitable by protein conjugates prepared with anti-idiotypic antibody and the toxic A chain of ricin. The idiotype specificity of the cytotoxicity was demonstrated by the inability of the same immunotoxin to inhibit an unrelated antibody response (anti-KLH) and by abrogation of specific toxicity in the presence of unconjugated anti-idiotype or antigen (AChR). Furthermore, immunotoxin prepared with an irrelevant antibody specificity failed to significantly inhibit either the anti-AChR or control antibody responses. Therefore, we suggest that idiotype-specific immunotoxins may be a useful addition or alternative to presently employed immunotherapies for autoimmune disease.
Perturbation of the autoimmune network. II. Immunization with isologous idiotype induces auto-anti-idiotypic antibodies and suppresses the autoantibody response elicited by antigen: a serologic and cellular analysis.
Authors: Zanetti M , Glotz D , Rogers J
Published: December 2022

We report on the humoral and cellular events following autologous immunization against an idiotype (Id62) borne on a murine monoclonal autoantibody to thyroglobulin, and their impact on the autoantibody response to thyroglobulin. BALB/c mice with a state of active auto-anti-idiotypic immunity and challenged with thyroglobulin in complete Freund's adjuvant 2 wk after the last immunization with idiotype were found to have a suppressed autoantibody response. This suppression could be adoptively transferred to syngeneic x-irradiated recipients by using whole spleen cells from idiotype-primed mice. Transfer of separate T and B lymphocyte populations proved instrumental in disecting humoral from cellular events and in establishing that whereas B cells were required for transferring an intact anti-idiotype antibody response, T cells from idiotype-primed mice were necessary to transfer suppression. These findings contribute to our understanding of the interrelationship between antigen, idiotype, and anti-idiotype in the immune response to self-antigens, and the role of certain idiotypes in regulating autoimmune responses.
Role of interleukin 1 in early T cell development: Lyt-2-L3T4- thymocytes bind and respond in vitro to recombinant IL 1.
Authors: Howe R C , Lowenthal J W , MacDonald H R
Published: December 2022

Thymocytes that bear neither Lyt-2 nor L3T4 differentiation antigens (2-4- thymocytes) contain the precursors for mature L3T4+Lyt-2- and Lyt-2-L3T4+ T cells. In the present study we determined the capacity of 2-4- cells to respond to recombinant interleukin 1 (rIL 1) in vitro. The presence of rIL 1 enhanced IL 2-dependent proliferation to the lectins Con A and PHA by threefold to eightfold. In a second assay, rIL 1 enhanced proliferation and IL 2 production by 2-4- cells in response to phorbol myristate acetate (PMA) and the calcium ionophore, ionomycin. Using a direct IL 1 binding assay, we were able to detect both high-affinity (Kd approximately 5 pM) and low-affinity (Kd approximately 200 pM) classes of IL 1 receptors on freshly isolated 2-4- cells. Bound IL 1 was rapidly internalized, suggesting that such receptors were functional. These results are compatible with a role for interleukin 1 during thymocyte maturation.
A short synthetic peptide fragment of human interleukin 1 with immunostimulatory but not inflammatory activity.
Authors: Antoni G , Presentini R , Perin F , Tagliabue A , Ghiara P , Censini S , Volpini G , Villa L , Boraschi D
Published: December 2022

Short peptide fragments of human and murine interleukin 1 (IL 1) were synthesized on the basis of their predicted exposure on the surface of the molecule in an attempt to identify the minimal structure responsible for the immunostimulatory activity of IL 1. One of these peptides, a fragment of nine residues of human IL 1 beta (VQGEESNDK, fragment 163-171), showed high T cell activation capacity, as judged by its ability to stimulate murine thymocyte proliferation and to potently induce interleukin 2 production in spleen cells. On the other hand, the 163-171 peptide was devoid of prostaglandin-inducing capacity in vitro and pyrogenic activity in vivo, two inflammatory features peculiar to the entire hu IL 1 beta molecule. Thus we propose that this peptide may represent one of the portions of hu IL 1 beta responsible for its immunostimulatory capacity.
The occurrence of anti-3-fucosyllactosamine antibodies and their cross-reactive idiotopes in preimmune and immune mouse sera.
Authors: Umeda M , Diego I , Marcus D M
Published: December 2022

The carbohydrate determinant 3-fucosyllactosamine (3-FL), Gal(beta 1-4)[Fuc alpha 1-3]GlcNAc-R, which is also known as SSEA-1 or as the X determinant, is very immunogenic in BALB/c mice. Many monoclonal antibodies directed against this structure have been obtained by immunization of mice with murine teratocarcinomas and human carcinomas and myeloid cells. We have undertaken an analysis of the regulation of these antibodies and of their idiotypic, structural, and genetic diversity. We have described previously the preparation of syngeneic monoclonal anti-idiotypic antibodies (6C4 and 6B1) that reacted with 50% of a panel of monoclonal anti-3-FL antibodies. In this study, we have examined the occurrence of anti-3-FL antibodies and their cross-reactive idiotopes in the sera of unimmunized and immunized mice. All BALB/c sera examined had more naturally occurring antibodies against 3-FL than against four other glycolipid antigens, and the 6C4 and 6B1 idiotopes were also detected in these sera. Approximately 25% of the anti-3-FL antibodies could be removed from a pool of BALB/c sera by a 6C4 affinity column, and the eluate from this column exhibited strong binding to 3-FL antigens. After a single i.v. injection of a 3-FL-positive glycolipid coated on Salmonella minnesota, anti-3-FL titers rose in BALB/c mice. The level of 6B1 idiotope rose in most mice, but the idiotope level showed no correlation with anti-3-FL titers. Naturally occurring antibodies against 3-FL were also noted in the sera of AKR, C3H/He, DBA/2, BALB/c-nu/nu, and CBA/CaHN mice but not in C57BL/6, SM, or CBA/N mice. A single i.v. injection of antigen elicited an antibody response in C3H/He mice but not in C57BL/6, SM, or DBA/2 mice. These data indicate that several strains of mice have more naturally occurring IgM antibodies against the 3-FL structure than against other glycolipids, and that this response may be genetically regulated. The 6C4 and 6B1 cross-reactive idiotopes that we have identified previously on monoclonal antibodies are also present in preimmune and immune sera. The existence of a population of B lymphocytes that are primed against the 3-FL determinant accounts in part for the immunogenicity of this structure.
Stimulatory effects of retinoic acid on macrophage interaction with blood forms of Trypanosoma cruzi: involvement of transglutaminase activity.
Authors: Wirth J J , Kierszenbaum F
Published: December 2022

The effects of retinoic acid (RA; vitamin A acid) on macrophage function were investigated by measuring the capacities of mouse peritoneal macrophages to associate with (i.e., bind and internalize) and kill the unicellular parasite Trypanosoma cruzi. The presence of 10(-8) to 10(-6) M RA in co-cultures of macrophages and blood forms of the parasite markedly increased their interaction as evidenced by significant increases in both the percentage of phagocytes associating with parasites and the average number of parasites per 100 cells. A similar effect was produced when either the macrophages or the trypanosomes were pretreated with RA, suggesting that both cell types could contribute to the noted effect. Although RA might have enhanced parasite-macrophage association by binding to both, its ability to stimulate phagocytosis was independently evidenced by a significant increase in the uptake of latex particles. RA-treated macrophages also took up larger numbers of dead T cruzi, denoting that parasite viability (i.e., infectivity) was not necessary for the production of the RA effect. The minimum pretreatment time for RA to significantly stimulate macrophage association with T. cruzi was 30 min, although a 45-min pretreatment was necessary for a maximal effect to be seen under our experimental conditions. The RA effect was reversible because, once optimally induced, it remained demonstrable for only 30 to 60 min after removal of the reagent; however, the effect persisted for at least 3 hr if RA was not removed. Transglutaminase activity appeared to be involved in the RA effect, because the latter was abrogated when the macrophages were treated with RA in the presence of cystamine, methylamine, or monodansylcadaverine, all of which inhibit transglutaminase activity by different mechanisms. RA also increased the capacity of macrophages to kill parasites internalized before the treatment. This cytotoxic capacity was inhibited by catalase, indicating that H2O2 played a role in the killing mechanism. RA treatment significantly increased the proportion of macrophages capable of reducing nitroblue tetrazolium. The present results indicated that RA was capable of activating macrophages, leading to greater uptake and killing of a protozoan parasite.
Defective suppressor cell function mediated by T8+ cell lines from patients with progressive multiple sclerosis.
Authors: Antel J , Bania M , Noronha A , Neely S
Published: December 2022

Activated suppressor cell function, induced with either concanavalin A or OKT3 and mediated by either unfractionated mononuclear cells or "panning" enriched T8+ cells, freshly isolated from peripheral blood, is reduced in patients with progressive multiple sclerosis (MS) as compared with control donors. In this study, we generated T8+ cell lines from the peripheral blood of these same patients and controls. Suppressor activity, mediated by T8+ cells exposed to OKT3 on days 1, 7, and 14 of culture and then treated with mitomycin C on day 16, was significantly reduced in the MS group (mean percent suppression 13% +/- 5) as compared with the control group (68% +/- 6, n = 8, p less than 0.001). No differences were noted in [3H]thymidine uptake by the OKT3-stimulated T8+ cell lines of MS and control groups. Mean percent suppression mediated by T4+ cell lines did not differ between MS and control groups (15% +/- 4, n = 3, vs 22% +/- 2, n = 4). These current data suggest that the previously observed defect in T8+ cell-mediated activated suppressor cell function in MS is a persistent one, favoring the postulate that the defect reflects intrinsic alterations in this cell population rather than a transient effect of serum factors on T8+ cell function.
Prazosin treatment suppresses increased vascular permeability in both acute and passively transferred experimental autoimmune encephalomyelitis in the Lewis rat.
Authors: Goldmuntz E A , Brosnan C F , Norton W T
Published: December 2022

Prazosin, an antagonist of the alpha 1-adrenoceptor, has been found to suppress the clinical and histologic expression of experimental autoimmune encephalomyelitis (EAE) in the Lewis rat. This effect appears to be specific for the alpha 1-receptor. To determine the effect of this drug on vascular permeability to serum proteins and inflammatory cells, leakage of serum proteins into the central nervous system (CNS) was measured with [125I]albumin, and quantitation of cellular inflammation was determined by an estimation of total DNA. The results show that in both actively induced and passively transferred models of the disease, treatment with prazosin significantly suppresses leakage of serum proteins into the CNS but does not significantly suppress the increase of DNA. The results of the [125I]albumin studies additionally support the conclusion that the extent of vascular permeability to serum proteins in the spinal cord is a significant correlate of clinical disease. The results of the DNA estimation were at variance with the histologic evidence of cellular infiltration. We conclude that treatment with prazosin has a significant effect on the development of vascular edema in EAE. These results additionally validate a role for the adrenergic receptor in the development of EAE, and support the hypothesis that the primary site of action of prazosin is on the vascular alpha 1-adrenoceptor.
Mitogenic effect of PMA + IL 2 on subpopulations of corticoresistant thymocytes.
Authors: Dupuy d'Angeac A , Monis M , Rème T
Published: December 2022

The proliferative response of subpopulations of corticoresistant thymocytes (CRT) to phorbol-12-myristate-13-acetate (PMA) + interleukin 2 (IL 2) was investigated. Thymocyte subpopulations were selected by the indirect "panning" technique, and their purity was checked by cytofluorometry. Microcultures were set up with an optimal concentration of PMA, EL4 supernatant, or pure IL 2 obtained by recombinant DNA technology (r-IL 2) in the presence or in the absence of accessory splenic adherent cells (SAC). Under these conditions, only the Lyt-2+ CRT proliferated, and this response was IL 2-dose-dependent and was increased by accessory cells. When the calcium ionophore A23187 was added to the cultures, the proliferation of L3T4+ CRT was greatly increased. These results were confirmed by cultures at limiting dilution of positively selected Lyt-2+ and L3T4+ subpopulations of CRT at optimal concentrations of PMA, r-IL 2, A23187, and accessory cells. These results are consistent with the idea that two signals are necessary to activate L3T4+ CRT, whereas only IL 2 is necessary for PMA-induced proliferation of Lyt-2+ CRT. Finally, unlike the case of lectin-induced proliferation of Lyt-2+ and L3T4+ CRT, the presence of accessory cells or cell-cell contact is important for optimal response to PMA + IL 2.
Natural suppressor activity in graft-vs-host spleen and normal bone marrow is augmented by IL 2 and interferon-gamma.
Authors: Holda J H , Maier T , Claman H N
Published: December 2022

Natural suppressor (NS) cells isolated from the spleens of mice 34 or more days after induction of chronic graft-vs-host disease showed potent suppressor activity that was dependent on the presence of lymphokines such as those found in lectin-free Con A supernatant (CAS). Both IL 2 and IFN-gamma were found to enhance NS activity, with IFN-gamma being the most active molecule. To generalize these findings, normal adult bone marrow (BM), a second environment where NS activity has been reported, was examined. Normal adult BM cells nonspecifically suppressed both B and T cell mitogen responses. BM suppression could also be enhanced by the addition of CAS to the cultures. Removal of plastic-adherent cells, Thy-1.2-positive cells, or B cells did not significantly diminish suppression or remove the ability to enhance suppression with CAS. When isolated on discontinuous Percoll gradients, BM suppressor cells banded in the less dense fractions, and the suppression in these bands was also enhanced by lymphokines. The suppressive activity of these cells was greatly enhanced by the addition of CAS, IFN-gamma, or IL 2. However, IFN-gamma appears to be a more potent enhancing molecule, being active at levels between 1 and 10 U/ml.
Recombinant human interferon-gamma inhibits formation of human osteoclast-like cells.
Authors: Takahashi N , Mundy G R , Roodman G D
Published: December 2022

Interferon-gamma (IFN-gamma) inhibits osteoclastic bone resorption in vitro, but the mechanism responsible for this inhibition is unknown. We have used a long-term human marrow culture system that forms multinucleated cells (MNC) with osteoclast characteristics to test the effect of recombinant human IFN-gamma on MNC formation. The addition of 1,25-dihydroxy-vitamin D3 (1,25D3) at 10(-8) M to these cultures significantly increased both MNC formation and the number of nuclei per MNC. IFN-gamma at 100 U/ml strongly inhibited both of these effects of 1,25D3 in this system. IFN-gamma significantly inhibited MNC formation at very low concentrations (4 U/ml), with 10 U/ml inhibiting 1,25D3-stimulated MNC formation by 50%. In contrast, 100 U/ml of IFN-gamma were required to inhibit the growth of granulocyte-macrophage colony-forming cells, the probable progenitor for MNC, by 50%. Treatment of cultures with IFN-gamma for only the first or last week of culture significantly inhibited MNC formation stimulated by 1,25D3. Autoradiographic studies with [3H]thymidine showed that IFN-gamma did not inhibit proliferation of precursors for MNC. Additionally, IFN-gamma inhibited MNC formation stimulated by parathyroid hormone or interleukin 1. These results suggest that IFN-gamma inhibits MNC formation, and that IFN-gamma inhibits bone resorption in part by inhibiting osteoclast formation.
Effect of cyclosporine A in erythema nodosum leprosum.
Authors: Uyemura K , Dixon J F , Wong L , Rea T H , Modlin R L
Published: December 2022

Erythema nodosum leprosum (ENL) is a reactional state of lepromatous leprosy in which the loss of suppressor cell function, decrease in suppressor cell numbers, and increase of interleukin 2 production are observed. We reasoned that cyclosporine A (CsA), by opposing these immune responses, could suppress the ENL reaction and restore patients to the quiescent lepromatous state. We tested this hypothesis in vitro by measuring the effect of CsA on M. leprae-triggered suppressor cells. In 24 of 25 patients with ENL, suppressor cell activity was restored by CsA. The target of CsA appeared to be macrophages. These findings are significant in that they provide the first evidence for the potential efficacy of CsA in the treatment of ENL. Preliminary clinical trials indicate a beneficial therapeutic effect associated with increased T suppressor cells in lesions.
Immunosuppression in viral oncogenesis. III. Effects of virus infection on interleukin 1 and interleukin 2 generation and responsiveness.
Authors: Strayer D S , Horowitz M , Leibowitz J L
Published: December 2022

Malignant rabbit fibroma virus (MV) is an oncogenic immunosuppressive leporipoxvirus. We studied the effects of MV infection and MV-associated tumor-induced suppressor factor (TISF) on the production of and responsiveness to interleukins 1 and 2. Adherent cells from MV tumor-bearing rabbits elaborate adequate amounts of IL 1 in response to E. coli endotoxin. Neither live virus nor TISF alters the production or the responsiveness to IL 1. However, when we examined spleen cells from rabbits 7 days after MV inoculation, we noted that their ability to produce and respond to IL 2 is deficient. Despite their relatively poor capacity to produce IL 2, these spleen cells express receptor for IL 2 in normal amounts, as measured by the monoclonal antibody 7D4. TISF derived from T lymphocytes from MV tumor-bearing rabbits is by itself capable of inhibiting partially normal secretion of IL 2 and also the response of the cloned murine T cell line HT-2 to added IL 2. Full expression of the immunosuppressive capacity of spleen cells from MV tumor-bearing rabbits requires cell-cell contact, however, and cannot be replaced by either live virus or spleen cell supernatants. Such spleen cells inhibit normal mitogen responsiveness, a defect not remedied by adding exogenous IL 2. Immunologic dysfunction induced by MV infection is transient, and by 11 days after virus inoculation, actively mediated recovery from immunosuppression is observed. We found that spleen cells from rabbits studied 11 days postinoculation secreted IL 2 normally. Thus, immunologic dysfunction secondary to infection with malignant rabbit fibroma virus reflects deficiencies in both elaboration of and response to IL 2, and return of immune function later in the course of the infection is associated with return of the ability of lymphocytes to secrete IL 2.
Two interleukin 1 genes in the mouse: cloning and expression of the cDNA for murine interleukin 1 beta.
Authors: Gray P W , Glaister D , Chen E , Goeddel D V , Pennica D
Published: December 2022

A human interleukin 1 beta (IL 1 beta) cDNA probe was utilized to identify a homologous murine cDNA clone. The murine cDNA encodes a 269-residue protein which is 67% homologous to human IL 1 beta. The murine sequence was engineered for expression in mammalian cells and directs the synthesis of biologically active IL 1. This protein, termed murine IL 1 beta, is only 22% homologous with the previously described murine IL 1 sequence. Both IL 1 alpha and IL 1 beta are encoded by single genes, but IL 1 beta mRNA is about fivefold more abundant in a stimulated macrophage cell line.
Stimulation of B cell growth and differentiation by murine recombinant interleukin 1.
Authors: Chiplunkar S , Langhorne J , Kaufmann S H
Published: December 2022

Purified splenic B cells from C57BL/6 mice were separated into high-density (resting) and low-density (activated) B cells. Separated B cell populations were cultured at low cell densities (1 X 10(4) cells/well) with recombinant interleukin 1 (r-IL 1) alone or in combination with dextran sulfate (DXS) or anti-IgM monoclonal antibodies (alpha IgM mab), respectively, and proliferative responses were determined. R-IL 1 alone, as well as in synergy with alpha IgM mab or DXS, respectively, stimulated the growth of low-density B cells. Moreover, r-IL 1 and alpha IgM mab costimulated replication of high-density B cells. Separated B cell populations (1 X 10(5) cells/well) were cultured with r-IL 1 alone or in combination with DXS or alpha IgM mab, respectively, and the generation of plaque-forming cells was determined. R-IL 1 alone, as well as in synergy with DXS, stimulated the differentiation of low-density B cells into Ig-secreting cells. These findings suggest that r-IL 1 has B cell growth and differentiation factor activity and is operative on high- and low-density B cells. Thus, IL 1 may play an important role in B cell growth and maturation.
Small bowel mucosa from celiac patients generates 15-hydroxyeicosatetraenoic acid (15-HETE) after in vitro challenge with gluten.
Authors: Krilis S A , Macpherson J L , de Carle D J , Daggard G E , Talley N A , Chesterman C N
Published: December 2022

Celiac disease (gluten-sensitive enteropathy [GSE]) is a disorder characterized by small intestinal mucosal injury caused by dietary exposure to wheat gluten and similar proteins. There is evidence that the mucosal injury is immunologically mediated and there is an inflammatory infiltrate present in the mucosa. It is postulated that release of lipid-derived inflammatory mediators may be involved in the pathogenesis of the mucosal injury. Jejunal mucosal biopsy samples from patients with GSE and from a group of patients who were subsequently shown to have normal jejunal mucosa were incubated with tritiated arachidonate and a peptic/tryptic digest of either gluten or casein. Generation of lipid-derived inflammatory mediators was measured by beta-scintillation counting after separation of metabolites by reverse-phase high performance liquid chromatography with two different buffer systems. The predominant arachidonic acid metabolite generated was 15-hydroxyeicosatetraenoic acid (15-HETE). Mucosa from newly diagnosed GSE patients on a normal diet generated more 15-HETE than either control patients or GSE patients maintained on a gluten-free diet. In addition, gluten acted as a specific stimulus to 15-HETE production by mucosa from the GSE patients on a normal diet. 15-HETE has a number of biologic effects that could contribute to the mucosal changes seen in GSE, and the specific release of 15-HETE by gluten suggests involvement in the pathogenesis of the disorder.
Influenza virus infection induces functional alterations in peripheral blood lymphocytes.
Authors: Lewis D E , Gilbert B E , Knight V
Published: December 2022

This report describes alterations in functional responses to lectin-induced stimulation of peripheral blood lymphocytes and in the natural killer cell (NKC) activity, of college students, obtained during an outbreak of influenza A/Philippines/2/82(H3N2) virus infection. These results are compared with similar observations in college students with an acute, febrile, noninfluenzal respiratory illness that occurred during the same outbreak. The lymphopenia typical of influenza during acute illness was shown to be due to a reduction in both T and B cells without alteration in the CD4:CD8 ratio. In addition, phytohemagglutinin and concanavalin A responses were reduced and NKC activity was increased, while pokeweed mitogen reactivity was unaltered at the time of admission to the study. Patients with noninfluenzal illness showed early polymorphonuclear leukocytosis and a similar lymphopenia. Lymphocyte functions were virtually unchanged during acute illness in noninfluenza patients. The relatively specific alterations in lymphocyte responses to lectin-induced stimulation in influenza patients may indicate that the peripheral T cells are incapable of activation via the CD3 or CD2 activation pathways. In addition, increased NKC activity in the periphery may be reflective of increased NKC activity in the lung. Influenza-infected individuals with higher NKC activity at the time of admission to the study also took longer to recover. Finally, the early lymphopenia and the later neutropenia in the influenza-infected patient may represent migration of these cells from the circulation to the infected respiratory tract as a consequence of infection.
Therapy of rat autoimmune disease by a monoclonal antibody specific for T lymphoblasts.
Authors: Schluesener H , Brunner C , Vass K , Lassmann H
Published: December 2022

The central role of T lymphocytes in the initiation, regulation and propagation of autoimmune diseases defines them as most suitable targets for selective immunotherapy. The recent advance in culturing human and animal T cell lines allows us to select monoclonal antibodies specific for differentiation antigens expressed by activated T lymphocytes. We selected a monoclonal antibody cytotoxic for a subpopulation of activated rat T cells. In vivo, this antibody effectively blocks immune responses to foreign antigens or autoantigen and prevents development of autoimmune diseases like experimental allergic encephalomyelitis and adjuvant arthritis. Even already established disease can be blocked by a single injection of antibody. Furthermore, this monoclonal antibody can be used to monitor the course of autoimmune disease progression from peripheral blood samples.
The released interleukin 2 receptor binds interleukin 2 efficiently.
Authors: Rubin L A , Jay G , Nelson D L
Published: December 2022

The released interleukin 2 receptor (IL 2R) molecule was characterized in order to clarify its biochemical structure and to determine its functional capacity. Enzymatic digestions demonstrated that the released IL 2R, like the cell surface IL 2R, is a complex glycoprotein, modified by the addition of both N- and O-linked carbohydrates and sialic acid residues. It has a peptide backbone that is approximately 10 Kd smaller than that of its membrane-associated counterpart. Affinity chromatography demonstrated that released IL 2R from either an HTLV-I-positive T cell line (HUT-102) or PHA-activated normal peripheral lymphocytes binds efficiently to purified recombinant IL 2. Furthermore, the interaction between the growth factor and the released receptor does not appear to require any accessory molecules. These observations suggest a potentially significant role for the released IL 2R in the regulation of IL 2-dependent lymphocyte functions.
Characterization of primate bronchoalveolar mast cells. I. IgE-dependent release of histamine, leukotrienes, and prostaglandins.
Authors: Wells E , Harper S T , Jackson C G , Mann J , Eady R P
Published: December 2022

Large numbers of functional mast cells were obtained by bronchoalveolar lavage (BAL) of Macaca arctoides monkeys that had been infected with the nematode Ascaris suum. These lavage cells, of which 21% were mast cells, released histamine, LTC4, and PGD2 in a concentration-dependent fashion when challenged with ascaris antigen or antibody to human IgE. However, there was no release of histamine when these cells were challenged with compound 48/80. The amount of mediator released was highly dependent on the sensitivity of the cells to immunologic challenge, but was generally in the range of 2 to 5 micrograms histamine (30 to 70% of total), 20 to 80 ng LTC4, and 100 to 300 ng PGD2 per 10(6) mast cells when maximally challenged. Other eicosanoids measured were released only in much smaller quantities. Maximal values were 4 ng LTB4, 2 ng PGE2, and approximately 10 to 20 ng PGF2 alpha per 10(6) mast cells. The amount of LTC4 and PGD2 released correlated with the release of histamine, the calculated regression line indicating that 18 ng LTC4 and 50 ng PGD2 were released per microgram of histamine released. This correlation suggests that the majority of the LTC4 and PGD2 released was probably mast cell-derived. Further support for this conclusion was given by the observation that when lavage cells were fractioned on continuous Percoll gradients, the ability to release LTC4 and PGD2 on immunologic challenge coincided with the peak of mast cells.
The presence of antibody in mice chronically infected with Schistosoma mansoni which blocks in vitro killing of schistosomula.
Authors: Yi X Y , Simpson A J , de Rossi R , Smithers S R
Published: December 2022

We have previously reported that IgM monoclonal antibodies (mAb) that recognize surface carbohydrate determinants shared between schistosomula, cercariae, and miracidia block antibody/complement dependent killing of schistosomula in vitro. Binding assays that make use of one of the IgM mAb labeled with 125I demonstrated that serum from chronically infected mice (CMS) contained high levels of competing antibody, whereas serum from mice vaccinated with irradiated cercariae (VMS) contained little antibody of this specificity. Absorption of CMS with cercariae that removed antibodies to schistosomulum surface carbohydrate determinants increased its ability to kill schistosomula in vitro; absorption of VMS with cercariae failed to alter the lethal activity of the serum. Furthermore, fractionation of CMS by protein A Sepharose chromatography demonstrated that the IgG fraction had an increased lethal activity compared with unfractionated serum; this result was not seen with VMS. Finally, the IgM fraction of CMS was shown to block in vitro killing of the IgG fractions of both CMS and VMS. These data suggest that the blocking activities observed with the IgM mAb are contained within the serum of chronically infected mice but not in the serum of mice vaccinated with irradiated cercariae.
The immune response to Moloney murine leukemia virus-induced tumors: induction of cytolytic T lymphocytes specific for both viral and tumor-associated antigens.
Authors: Flyer D C , Burakoff S J , Faller D V
Published: December 2022

The specificity of CTL generated against tumors induced by murine leukemia viruses (MuLV) has been reported to parallel the expression of two serologically defined tumor cell surface antigens--the cross-reactive FMR antigen expressed on the surface of tumors induced by Friend, Moloney, and Rauscher MuLV, and the Gross cell surface antigen (GCSA) expressed on tumors induced by AKV/Gross MuLV. We examined the specificity of CTL generated against MuLV-induced tumors and identified two distinct patterns of reactivity. The first follows the traditional pattern of FMR vs GCSA reactivity as assessed on a panel of established MuLV-induced lymphomas. However, CTL exhibiting this pattern of reactivity are incapable of lysing MuLV-infected fibroblasts. CTL exhibiting the second pattern of reactivity are capable of lysing MuLV-induced lymphomas as well as MuLV-infected fibroblasts. In addition, these CTL exhibit extensive cross-reactivity between lymphomas and fibroblasts infected by both groups of MuLV. Our results suggest that CTL exhibiting the traditional FMR vs GCSA pattern of reactivity are directed against a tumor-associated antigen and not against virus-encoded antigens, and that CTL directed against MuLV-encoded antigens demonstrate extensive cross-reactivity, including the ability to lyse AKV-infected cells.
Chromosomal location of the genes encoding complement components C5 and factor H in the mouse.
Authors: D'Eustachio P , Kristensen T , Wetsel R A , Riblet R , Taylor B A , Tack B F
Published: December 2022

Complementary DNA probes corresponding to the factor H and C5 polypeptides have been used to determine the chromosomal localizations of these two complement components. Both probes revealed complex and polymorphic arrays of DNA fragments in Southern blot analysis of mouse genomic DNA. Following the distribution of these bands in panels of somatic cell hybrids carrying various combinations of mouse chromosomes on a constant rat or Chinese hamster background allowed the localization of the C5-associated fragments to proximal chromosome 2 and the localization of the factor H-associated fragments to chromosome 1 or chromosome 3. Following the inheritance of DNA restriction fragment-length polymorphisms revealed by the probes in recombinant inbred mouse strains allowed the factor H-associated fragments to be mapped to Sas-1 on chromosome 1, and the C5-associated fragments to be mapped to Hc. Analysis of three-point crosses, in turn, placed the latter locus 19 cM distal to Sd on chromosome 2. We have designated the two loci Cfh and C5, respectively. This genetic analysis raises the possibility that C5 and factor H are both encoded by complex loci composed of distinct structural and regulatory genes.
Differential interaction of the C3b/C4b receptor and MHC class I with the cytoskeleton of human neutrophils.
Authors: Jack R M , Ezzell R M , Hartwig J , Fearon D T
Published: December 2022

As measured by fluorescence microscopy and radioligand binding, C3b/C4b receptors (CR1) became attached to the detergent-insoluble cytoskeleton of human neutrophils when receptors were cross-linked by affinity-purified polyclonal F(ab')2 anti-CR1, dimeric C3b, or Fab monoclonal anti-CR1 followed by F(ab')2 goat anti-mouse F(ab')2. CR1 on neutrophils bearing monovalent anti-CR1 was not attached to the cytoskeleton. In contrast, cross-linked CR1 on erythrocytes and cross-linked MHC Class I on neutrophils were not cytoskeleton associated. A possible role for filamentous actin (F-actin) in the binding of cross-linked CR1 to neutrophil cytoskeleton was suggested by three observations. When neutrophils were differentially extracted with either Low Salt-detergent buffer or High Salt-detergent buffer, stained with FITC-phalloidin, and examined by fluorescent flow cytometry, the residual cytoskeletons generated with the former buffer were shown to contain polymerized F-actin, whereas cytoskeletons generated with the latter buffer were found to be depleted of F-actin. In parallel experiments, High Salt-detergent buffer was also found to release cross-linked CR1 from neutrophils. Second, depolymerization of F-actin by DNAse I released half of the cytoskeletal-associated cross-linked CR1. Third, immunoadsorbed neutrophil CR1, but not MHC Class I or erythrocyte CR1, specifically bound soluble 125I-actin. In addition, Fc receptor and CR3, other phagocytic membrane proteins of neutrophils, specifically bound 125I-actin. These data demonstrate that CR1 cross-linked on neutrophils becomes associated with detergent-insoluble cytoskeleton and that this interaction is mediated either directly or indirectly by actin.
Molecular mapping of murine I region recombinants. II. Crossing over in the E beta gene is restricted to a 4.5 kb stretch of DNA that excludes the beta 1 exon.
Authors: Saha B K , Raziuddin  , Cullen S E
Published: December 2022

The crossing over in five murine I-region recombinants (Is/Ik) was studied by restriction fragment length polymorphism analysis after Southern blot hybridization by using I-region-specific probes. These recombinants included three recently developed strains, B10.ASR1, B10.ASR11, and B10.ASR12; and two strains B10.S(9R) and B10.HTT derived earlier. Although these recombinants were reciprocal in haplotype orientation to the three recombinants we reported recently, these too crossed over within the same 7 kb stretch of DNA in the E beta gene. This 7 kb stretch of DNA included the 3' half of the first intron, the beta 1 exon, the second intron, and the beta 2 exon. A comparison of the cDNA sequences of the two parental E beta alleles revealed that although the beta 2 exons were identical, there were several nucleotide differences between the two beta 1 exons. This allowed us to determine the parental origin of the beta 1 exon in the recombinants at the level of transcription by using S1 nuclease mapping. Thus we were able to show that in each case the 3' portion of the first intron and the beta 1 exon were upstream from the site of crossover. All eight recombinants involving the k and s haplotypes now can be mapped within a 4.5 kb stretch of DNA, which includes only the beta 1-beta 2 intron and the beta 2 exon of the E beta gene. These findings imply that the I-E molecules expressed in these recombinants will probably have conserved sequences and therefore will exhibit identical I-E-restricted immune responses, despite the fact that crossing over could have occurred at different sites within the beta 1-beta 2 intron.
Differential lack of class I H-2d antigen expression by sublines of the BALB/c S49 T cell lymphoma.
Authors: Joseph L J , Levy E , Ozato K , Hochman J , Shearer G M
Published: December 2022

Five different sublines of the BALB/c murine S49.1 T cell lymphoma were found to exhibit distinct patterns of absence of detectable H-2d class I major histocompatibility antigen expression. The results were demonstrated and verified by a) the generation of H-2Kd-, H-2Dd,Ld-, and H-2Ld-specific cytotoxic T lymphocytes that were assayed on S49.1 target cell lines, b) antibody-mediated cytotoxicity with the use of anti-H-2d monoclonal reagents, and c) flow microfluorometry. The five lines investigated were S49.1, T-25, T-25ADH, Thy-1-, and 100/0. None of these lines expressed detectable levels of Ld. S49.1 expressed both Kd and Dd, T-25 and T-25ADH expressed Dd but not Kd or Ld, Thy-1- expressed Kd but not Dd or Ld, and 100.0 did not express any detectable amounts of Kd, Dd, or Ld. These results indicate that K and D (and L) antigens can be expressed independently of each other and suggest that expression of class I antigens is controlled in a locus-specific manner.
Partial restoration of the lipopolysaccharide-induced proliferative response in splenic B cells from C3H/HeJ mice.
Authors: Kuus-Reichel K , Ulevitch R J
Published: December 2022

C3H/HeJ mice are hyporesponsive to the biologic effects of bacterial lipopolysaccharide (LPS), and their splenic B cells do not proliferate after exposure to LPS. The molecular basis of this hyporesponsiveness is unknown but it may result from defective membrane signal transduction after LPS binding. To examine this possibility, we added bioactive compounds in combination with LPS to C3H/HeJ B cell cultures in order to bypass the putative defect. The addition of PMA, monensin, or ionomycin, either alone or in combination, had no effect on C3H/HeJ B cell responses to LPS. In contrast, the addition of trypsin together with LPS resulted in a partial restoration of the proliferative response in C3H/HeJ splenic B lymphocytes. The maximal C3H/HeJ B cell response varied from 25 to 60% of the C3Heb/FeJ (LPS responder) B cell response. The trypsin-mediated enhancement of the LPS response was abrogated by pretreatment of the trypsin with the trypsin inhibitors DFP or TLCK. Pretreatment of the LPS with polymyxin B, which blocks lipid A-dependent reactions, also abrogated the trypsin effect. Because the C3H/HeJ B cell responds to all other B cell mitogens, we suggest that the defect is in an LPS-specific step and that the action of trypsin results in the restoration of the missing signal. At the present time the identity of this signal is not known, but the experiments described in this report provide a unique model to elucidate the basis of LPS hyporesponsiveness in splenic B cells from C3H/HeJ mice.
Differential expression of ecto-5' nucleotidase activity by functionally and phenotypically distinct subpopulations of human Leu-2+/T8+ lymphocytes.
Authors: Dianzani U , Massaia M , Pileri A , Grossi C E , Clement L T
Published: December 2022

Subsets of Leu-2+/T8+ cytotoxic/suppressor T lymphocytes were isolated by using various methods of purification and were investigated for expression of ecto-5' nucleotidase (5'NT) enzyme activity by radiochemical, cytochemical, and ultrastructural techniques. By using both the radiochemical and the cytochemical methods. T4-OKM1- cells displayed higher 5'NT activity in comparison with the entire T4- subpopulation. Analyses of the subpopulations of T4- (and predominantly Leu-2+) cells defined by the Leu-15 or Lyt-1 (9.3) monoclonal antibodies demonstrated that T4-Leu-15- and T4-Lyt-1+ cells displayed high 5'NT activity, whereas virtually no activity was present in T4-Leu-15+ and T4-Lyt-1-cells. At the ultrastructural level, the 5'NT reaction product was detected on the plasma membrane of a proportion of nongranular Leu-2+/T8+ lymphocytes, but no activity was found on cells with a granular lymphocyte (GL) morphology. 5'NT activity was also analyzed in peripheral blood mononuclear cells from one patient with expanded numbers of GL and two patients with GL leukemia. The enzymatic activity was significantly lower in these patients than in normal controls. This study provides new cytochemical evidence demonstrating the heterogeneity of Leu-2+/T8+ cells, and indicates that the population with the suppressor phenotype and function (Leu-15+/Lyt-1-, GL morphology) displays low or absent 5'NT activity, whereas the population composed of cytotoxic cell precursors (Leu-15-/Lyt-1+, nongranular morphology) has high 5'NT activity. Implications of these data for the interpretation of low 5'NT activity described in several immunodeficiency states and lymphoproliferative disorders are discussed.
Destruction of autologous human lymphocytes by interleukin 2-activated cytotoxic cells.
Authors: Sondel P M , Hank J A , Kohler P C , Chen B P , Minkoff D Z , Molenda J A
Published: December 2022

Human and murine lymphocyte populations differentiate into lymphokine activated killer (LAK) cells after in vitro or in vivo exposure to interleukin 2 (IL 2). LAK cells mediate destruction of neoplastic tissue in vitro and have been reported to spare normal tissue. However, systemic toxicity is observed in mice and patients receiving IL 2 infusions. Some aspects of this toxicity are similar to that seen in graft-vs-host disease, suggesting that IL 2 may cause an immune-mediated destruction of normal tissues. We have evaluated this issue by examining the destructive potential of fresh human lymphocytes cultured in media containing highly purified recombinant human IL 2. In the absence of any exogenous antigen or allogeneic stimulating cells, strong proliferative responses were induced after 6 days of exposure to IL 2. Lymphocytes harvested from these 6-day cultures were highly cytotoxic to K562 and Daudi target cells. These IL 2-activated cells were also cytotoxic against autologous and allogeneic normal lymphocyte target cells. This autologous lymphocyte destruction was detected in media containing autologous serum and was directly dependent on the concentration of IL 2 added to the cultures. These studies demonstrate that populations of IL 2-activated lymphocytes, containing LAK activity, can mediate low-level but significant destruction of normal lymphocytes in vitro.
Effect of interleukin 1 on the expression of interleukin 2 receptor (Tac antigen) on human natural killer cells and natural killer-like cell line (YT cells).
Authors: Shirakawa F , Tanaka Y , Eto S , Suzuki H , Yodoi J , Yamashita U
Published: December 2022

The effect of interleukin 1 (IL 1) on the expression of interleukin 2 receptor (IL 2R/Tac antigen) on human natural killer (NK) cells and the NK-like cell line, YT was studied with the use of a fluoresceinated anti-IL 2R monoclonal antibody and a Spectrum III flow cytofluorometer. IL 2R was expressed on approximately 10% of NK cells. The expression of IL 2R on NK cells was increased to approximately 25% by the in vitro culture with monocytes or IL 1 and to a less extent by the culture with IL 2 or interferon-gamma (IFN-gamma). IL 2R was expressed on approximately 50% of YT cells without any stimulations. The expression of IL 2R on YT cells was increased up to almost 100% by the culture with IL 1 or monocytes, but not with IL 2, IFN-alpha, IFN-beta, IFN-gamma, or lectins such as concanavalin A and phytohemagglutinin-P. IL 1 absorbed with YT cells or murine thymocytes lost both IL 1 activity detected by the stimulation of murine thymocyte proliferative response and enhancing activity of IL 2R expression on YT cells, suggesting that IL 1 has both activities. However, the assay system of the expression of IL 2R on YT cells is much more sensitive than the stimulation of murine thymocyte proliferative response. By the kinetic study, the enhancement of IL 2R expression was induced by only a 2-hr incubation of YT cells with IL 1. This enhancement did not proceed at 4 degrees C or by the treatment of YT cells with actinomycin D or cycloheximide, suggesting that this enhancement is energy dependent and requires the synthesis of RNA and protein but not DNA. Thus IL 1 plays an important role for the regulation of the expression of IL 2R on NK cells, and IL 1-dependent IL 2R expression on YT cells may give us a good model for the study of the molecular mechanism of the regulation of IL 2R expression.