The role of fetal calf serum in the primary immune response in vitro

The mode of action of 2-mercaptoethanol (2-ME) on the primary immune response in vitro was investigated. Fetal calf serum (FCS) was preincubated with 2-ME and lyophilized to remove free 2-ME. This 2-ME- treated FCS was able to substitute the function of adherent cells in the primary immune response against sheep red blood cells (SRBC) in vitro; Fractionation of 2-tme-treated FCS on a Sephadex G-100 column showed that 2-ME acted on a high molecular serum component which after activation, could substitute for macrophages. In order to obtain a humoral immune response against SRBC in vitro, spleen cells require selected FCS. These "good" sera could be distinguished from "deficient" sera by their higher content of this 2-ME-activated factor. The height of the in vitro immune response to SRBC was dependent on the amount of activated factor added to the culture medium. FCS normally required in the culture medium could be completely replaced by the factor- containing fraction without deleterious effect on the culture medium. The factor should be added to the spleen cells during the first 24 h of culture and remain there for 72 h in order to obtain an optimal immune response. The factor could be partially absorbed by spleen cells but not by SRBC. The relationship between macrophage, 2-ME, and FCS in eliciting an in vitro primary immune response is discussed.     

Regulation of the immune response. I. The potentiation of in vivo and in vitro immune responses by Fc fragments

Fc fragments derived from human and murine Ig were found to be potent adjuvants when administered with antigen. Both the in vivo and in vitro anti- sheep erythrocytes (SRBC) responses were significantly enhanced by Fc fragments. The adjuvant effect was shown to be extremely dependent upon the dose of antigen used, with the greatest enhancement occurring when suboptimal doses of antigen are employed. The anti-genicity of the Fc molecule was not related to its adjuvanticity because homologous Fc was as potent an adjuvant as heterologous Fc. Moreover, human Fc fragments enhanced anti-SRBC responses in mice which were tolerant to human gamma globulin.     

The role of C5a in the innate immune response after experimental blunt chest trauma

The inflammatory response after severe blunt chest trauma often leads to acute lung injury and acute respiratory distress syndrome which are associated with high mortality rates. Whereas the role of innate immunity in acute lung injury has been broadly investigated, the immune response after blunt chest trauma is still poorly understood. Therefore, the role of complement and neutrophils was determined in bilateral lung injury induced by a single blast wave. The following time-points were investigated posttrauma: sham, 1, 6, 12, and 24 h. There was a time-dependent systemic activation of complement as determined by CH-50 and presence of C5a-dependent chemotactic plasma activity. Moreover, factor H, a complement regulatory protein, was increased systemically and locally after injury. Anti-C5a treatment immediately after trauma ameliorated these peaks. After an initial systemic leukopenic phase, a marked leukocytosis occurred. The latter was normalized by C5a blockade. In parallel, white blood cell count in bronchioalveolar lavage fluids was increased as a function of time and was significantly decreased by anti-C5a treatment. Trauma-induced lung injury was also associated with dramatic changes in neutrophil function, namely early enhanced chemotaxis and phagocytosis, followed by prolonged functional defects-all of which were ameliorated by anti-C5a treatment. Furthermore, blockade of C5a ameliorated the buildup of the proinflammatory cytokine TNF-alpha, diminished the increase of cytokine-induced neutrophil chemoattractant 1, and altered the levels of the anti-inflammatory cytokine IL-10.These data suggest that blunt chest trauma leads to systemic activation of complement and robust C5a generation, which causes perturbations in defensive functions of neutrophils. Thus, C5a might represent a potential target for therapeutic immunomodulation to prevent immune dysfunctions post-trauma and thereby, perhaps, the progression to acute respiratory distress syndrome.     

The secondary immune response to a hapten in vitro. Antigen concentration and the carrier effect

The in vitro secondary stimulation of the production of anti-hapten antibody has been analyzed with a view to elucidating the role of the carrier molecule and cell-to-cell interactions in this response. Stimulation was carried out on fragment cultures of the spleens of irradiated BALB/c mice which had been reconstituted with 3–4 x 10⁷ spleen cells from isologous mice previously immunized with DNP-Hy. The results indicated that the response was maximized by stimulation with DNP-Hy, the homologous complex, however anti-DNP antibody production could be obtained by stimulation with DNP on several nonhomologous carriers including poly-D-lysine, a poor immunogen. The results also indicated that while DNP-Hy and DNP-nonhomologous-carrier complexes were stimulatory at equally low DNP concentrations, at DNP concentrations over 10^–6 M DNP-Hy was stimulatory, while DNP on nonhomologous carriers was inhibitory. The results are interpreted as indicating that: (a) the affinity of the antigen-cell interaction is more likely determined by multivalent binding than by carrier recognition, (b) that a stimulatory interaction of a polyvalent antigen with a B-lymphocyte cannot be excluded, (c) that if cell-to-cell interaction is necessary for stimulation, then both cells may recognize the same determinant, and (d) that the marked enhancement of antigenic stimulation attributable to carrier recognition may result from stimulatory interactions of cells recognizing different antigenic determinants. A mechanism is postulated whereby stimulation is dependent on the formation of stable complexes resulting from two cells sharing in the binding of numerous antigen molecules. Cells recognizing carrier determinants would increase the probability of such interactions particularly at high antigen concentrations.     

Antigen recognition: in vitro studies on the specificity of the cellular immune response

Studies of the immunochemical specificity of antigen-induced thymidine-2-¹⁴C incorporation in lymph node cells obtained from animals immunized to a series of closely related α-DNP-oligolysines, ε-DNP-oligolysines, and oligolysines have shown that the sensitized cell exhibits an extraordinary degree of specificity for antigen. The sensitized cell is maximally stimulated by the homologous immunizing antigen and can discriminate among compounds which differ from one another only in the position of a dinitrophenyl group or D-lysine residue on an identical oligolysine backbone. These studies support the view that the immunogen is not degraded prior to the induction of the immune response, and that the majority of cells produced as a consequence of immunization have stereospecific antigen receptors for the DNP-oligolysine used to induce the response; a smaller and more variably sized population of cells is produced with receptors specific for the oligolysine portion of the immunizing antigen. When specifically sensitized lymph node cell cultures are stimulated in vitro by heterologous DNP-oligolysines, the oligolysine- and not the DNP-oligolysine-sensitive population of cells appears to play a crucial role in the specificity of such cross-reactions. It is concluded from these studies that the antigen receptor on the sensitized lymph node cell differs in both kind and degree from conventional antibody. The chemical nature of the receptor and the means by which this receptor reacts with antigen to initiate the biosynthetic or proliferative cellular immune response still remain undefined.     

IL-18及其受体在特发性血小板减少性紫癜患者Th1类细胞优势应答中的作用

Objective To evaluate the role of interleukin(IL)-18 and IL-18 receptor(IL-18R)in the predominant Thl type cytokine response in patients with immune thrombocytopenia(ITP).Methods Fifteen patients with active phase ITP,eighteen in remission and thirteen healthy controls were enrolled in this study.T-bet and GATA-3 mRNA levels in peripheral blood mononueleated cells(PBMNC)were measured by reverse transcfiptase polymerase chain reaction(RT-PCR);the plasma IL-18 level by enzyme linked immunosorbent assay(ELISA),the expression of IL-18R on CD3+ lymphocytes and total lymphocytes by flow cytometry(FCM).Results The T-bet mRNA levels in patients with active phase ITP was 3.572 fold as much as that in the controls(P＜0.05),while the GATA-3 mRNA levels were 0.378 foId of that in controls(P＜O.05).The levels of plasma IL-18 and IL-18R on CD3+ lymphocytes were significantly increased in active ph8se ITP than in remission phase and controls.There was no differenee in ratio of T-bet/GATA-3 between remitted ITP and controls and so was for T-bet mRNA,GATA-3 mRNA,plasma IL-18 and IL-18R on CD3+lymphocytes.Conclusion ITP as a disease of Thl-dominant response there is an unbalance between T-bet and GATA-3 in its active phase:IL-18 and IL-18R being upregulated.     

IL-18及其受体在特发性血小板减少性紫癜患者Th1类细胞优势应答中的作用

目的 探讨白细胞介素18(IL-18)及其受体(IL-18R)在特发性血小板减少性紫癜(ITP)患者Th1类细胞因子优势应答中的作用.方法 应用逆转录聚合酶链反应(RT-PCR)检测15例活动期和18例缓解期ITP患者外周血单个核细胞(PBMNC)中转录因子T-bet和GATA-3 mRNA的表达;应用ELISA法检测血浆中IL-18的变化;应用流式细胞术检测CD3+细胞和淋巴细胞表面IL-18R的表达.13名健康志愿者为正常对照.结果 ITP活动期患者PBMNC中T-bet mRNA表达水平(0.069±0.013)明显高于对照组(0.019±0.010)(P＜0.05),而GATA-3 mRNA的表达水平(0.002±0.001)明显低于对照组(0.005±0.002)(P＜0.05);血浆IL-18和CD3+细胞表面IL-18R表达水平较ITP缓解期患者和对照组显著增高.ITP缓解期患者T-bet与GATA-3 mRNA表达水平与对照组比较差异均无统计学意义(P值均＞0.05),T-bet/GATA-3比例基本恢复正常,血浆中IL-18和CD3+细胞表面IL-18R的表达水平也基本恢复正常.结论 ITP活动期患者表现为Th1优势应答,T-bet/GATA-3比例明显失衡,T-bet/GATA-3比例可作为ITP患者Th1类细胞极化的敏感指标;ITP活动期患者IL-18和IL-18R表达上调,可能为ITP患者的治疗提供一个新的治疗靶点.     

The role of adenosine in the control of immune function

Summary In the past several years the study of primary immunodeficiencies has led to an explosive growth of basic information on the pathophysiology of the immune system. In 1972 a deficiency of adenosine deaminase (ADA) was described in two patients with severe combined immunodeficiency (SCID). Shortly thereafter, deficiencies of other enzymes involved in the purine salvage pathway (i.e., purine nucleoside phosphorylase and ecto-5′-nucleotidase) were described in association, respectively, with defective T- and B-lymphocyte activity. Although the exact biochemical mechanism(s) in these immunodeficiencies is not known, elevated levels of adenosine, 2-deoxyadenosine and their metabolites occur in these patients. Adenosine inhibitsin vitro lymphocyte proliferation, T-lymphocyte-mediated cytolysis, monocyte chemotaxis and basophil histamine release. We have found that adenosine increases lymphocyte cAMP levels, by interacting with a specific plasma membrane receptor which leads to the activation of adenylate cyclase. We have also explored the influence of adenosine in the control of histamine release from human basophils and have shown that adenosine inhibits the IgE-mediated release reaction. The action of adenosine on basophils also appears to be mediated by a specific cell-surface receptor. Adenosine also plays a central and complex role in the control of transmethylation reactions. These reactions modulate several immune and inflammatory reactions, including monocyte chemotaxis, lymphocyte mitogenesis, T-lymphocyte-mediated cytolysis, and probably the IgE-mediated release of histamine from basophils. Thus, adenosine may act as an endogenous modulator of immune function by two separate but interrelated effects: its ability to interact with a cell-surface adenosine receptor, and/or to influence intracellular methylation. This work was supported in part by grants HL 14153 from the Heart and Lung Institute, AI 07290 from the Institutes of Allergy and Infectious Disease, National Institutes of Health (Bethesda, Md) and from theConsiglio Nazionale dette Ricerche (CNR), Roma, Italy, grant no. 79.02392.65. This is publication # 387, O’Neill Research Laboratories, The Good Samaritan Hospital, 5601 Loch Raven Boulevard, Baltimore, Md 21239. Recipient of RCDA AI 00231 from the National Institutes of Health, Bethesda, Md.     

Heterogeneity in vaccine immune response: the role of immunogenetics and the emerging field of vaccinomics

Recent advances in the fields of immunology, genetics, molecular biology, bioinformatics, and the Human Genome Project have allowed for the emergence of the field of vaccinomics. Vaccinomics encompasses the fields of immunogenetics and immunogenomics as applied to understanding the mechanisms of heterogeneity in immune responses to vaccines. In this study, we examine the role of HLA genes, cytokine genes, and cell surface receptor genes as examples of how genetic polymorphism leads to individual and population variations in immune responses to vaccines. In turn, this data, in concert with new high-throughput technology, inform the immune-response network theory to vaccine response. Such information can be used in the directed and rational development of new vaccines, and this new golden age of vaccinology has been termed "predictive vaccinology", which will predict the likelihood of a vaccine response or an adverse response to a vaccine, the number of doses needed and even whether a vaccine is likely to be of benefit (i.e., is the individual at risk for the outcome for which the vaccine is being administered?).     

Feedback suppression of the immune response in vitro. II. IgVH- restricted antibody-dependent suppression

Feedback suppression of the primary humoral immune response to sheep erythrocytes (SRBC) in vitro was induced with cell-free supernate material derived from antigen-(SRBC) activated B (sIg+) cells. This soluble products bears Ig determinants and binds to the eliciting antigen (SRBC). The activity of this antibody in suppressing anti-SRBC plaque-forming cell responses is restricted to spleen cell cultures containing B cells sharing VH genes with the B cells producing the suppressive antibody. The anti-hapten (trinitrophenyl) response to derivatized SRBC is not affected by antigen-primed B cells or their products. These data are compatible with suppression being mediated by anti-antigen antibody, either (a) via blockade of different SRBC epitopes recognized by a limited set of B cell clones in each mouse strain, (b) via triggering of an anti-idiotypic response, either antibody or suppressor T cell in nature, restricted to activity in cultures containing B cells sharing VH structures with the original antibody, or (c) via interference by preformed antibody with T cell help directed at idiotype bearing B cells.     

The role of Toll-like receptors in immune disorders

Toll-like receptors (TLRs) play an important role in innate immunity. Individual TLRs recognise microbial components that are conserved among pathogens. Such recognition initiates necessary inflammatory immune responses and induces subsequent activation of adaptive immunity. Studies in people with polymorphisms in genes encoding TLR signalling can elucidate the relationship between TLRs and human diseases, such as infectious diseases, atherosclerosis and immunodeficiency. Indeed, accumulating data in respect to TLR signalling suggest that TLRs are closely related with the pathogenesis of autoimmune diseases. This review looks at the role of TLRs in various immune disorders, and discusses the pathogenesis of diseases.     

The role of Toll-like receptors in immune disorders

Toll-like receptors (TLRs) play an important role in innate immunity. Individual TLRs recognise microbial components that are conserved among pathogens. Such recognition initiates necessary inflammatory immune responses and induces subsequent activation of adaptive immunity. Studies in people with polymorphisms in genes encoding TLR signalling can elucidate the relationship between TLRs and human diseases, such as infectious diseases, atherosclerosis and immunodeficiency. Indeed, accumulating data in respect to TLR signalling suggest that TLRs are closely related with the pathogenesis of autoimmune diseases. This review looks at the role of TLRs in various immune disorders, and discusses the pathogenesis of diseases.     

A dual role for the immune response in a mouse model of inflammation-associated lung cancer

Lung cancer is the leading cause of cancer death worldwide. Both principal factors known to cause lung cancer, cigarette smoke and asbestos, induce pulmonary inflammation, and pulmonary inflammation has recently been implicated in several murine models of lung cancer. To further investigate the role of inflammation in the development of lung cancer, we generated mice with combined loss of IFN-γ and the β-common cytokines GM-CSF and IL-3. These immunodeficient mice develop chronic pulmonary inflammation and lung tumors at a high frequency. Examination of the relationship between these tumors and their inflammatory microenvironment revealed a dual role for the immune system in tumor development. The inflammatory cytokine IL-6 promoted optimal tumor growth, yet wild-type mice rejected transplanted tumors through the induction of adaptive immunity. These findings suggest a model whereby cytokine deficiency leads to oncogenic inflammation that combines with defective antitumor immunity to promote lung tumor formation, representing a unique system for studying the role of the immune system in lung tumor development.     

Studies on the in vitro formation of antibodies. III. Induction of primary and secondary immune response in vitro]

Peritoneal cells from normal, unimmunized mice (female NMRI, 28-32 gr) produced in vitro primary and secondary immune response after induction with the bacteriophage T2 6 hours or 7 day resp. after establishing the cultures. We confirmed the induction of a primary and secondary immunological response in vitro in the very same culture by the following data: 1. In vivo the donor animals were not in contact with the antigen used. We found neither the phage nor its host E. coli B in the gut of 97 mice investigated and no humoral antibodies against T2. The kinetics of humoral antibody production in vivo by different doses of T2 also showed that there are no related or identical antigen structures incorporated in our animals. 2. The T2 neutralizing activity in the culture medium after the first induction had the sedimentation constant of 19.7 +/- 2.3 S (n = 9) but the activity found after the second induction sedimented with 8.1 +/- 0.7 S (n = 10). 3. The primary activity was more sensitive to mercaptoethanol than the secondary. 4. Complement was bound by the complex T2 + neutralizing activity.     

Fever and immunoregulation. III. Hyperthermia augments the primary in vitro humoral immune response

We have examined the possibility that hyperthermia, such as that occurring during fever, may benefit the immune response. The effect of temperature on the in vitro immune response of unprimed murine spleen cells against the antigen sheep erythrocytes was tested. Hyperthermia potently augmented the plaque-forming cell response. Temperature- sensitive events occurred early in the culture period. Subsets of lymphocytes were independently assessed for effects of temperature on their activation and function. We showed that the beneficial effect of elevated temperature on the plaque-forming cell response probably occurs during the priming stage of T helper cells, and neither improves the delivery of help or the activation of B cells, nor impairs suppressor T cell generation or function. We propose that this powerful immunopotentiating effect of hyperthermia may account for the selective value of the fever response. This suggests taht the monokine interleukin 1, which is the endogenous mediator of fever, may promote immune responses both through a direct action on lymphocytes, and indirectly by an action on the central nervous system resulting in fever.     

巨噬细胞极化在脓毒症免疫机制中的作用

脓毒症是由于感染引起的免疫功能失调，最终导致的多脏器功能障碍综合征。巨噬细胞作为先天性免疫和适应性免疫的重要组成成分之一，当微环境变化时，可分化成具有不同功能的表型，称为巨噬细胞极化。巨噬细胞极化在脓毒症的免疫调节中发挥重要作用，调控巨噬细胞极化有望成为未来脓毒症治疗的新靶点。因此，本文就巨噬细胞极化及其在脓毒症免疫机制中的作用进行综述。