scholarly journals Idiotypic repertoire of anti-hen eggwhite lysozyme antibodies probed with hybridomas. Selection after immunization of an IdX marker common to antibodies of distinct epitope specificity.

1981 ◽  
Vol 154 (3) ◽  
pp. 701-712 ◽  
Author(s):  
D W Metzger ◽  
A Furman ◽  
A Miller ◽  
E E Sercarz
Keyword(s):  
Primary Response ◽  
Lymphoid Cells ◽  
Secondary Response ◽  
Epitope Specificity

A panel of hybridoma antibodies obtained from lymphoid cells that were fused during a primary response ("early") or a secondary response ("late") gave results concordant with analysis of conventional, in vivo-produced anti-lysozyme idiotypes: early antibodies did not display the predominant anti-hen eggwhite lysozyme idiotype (IdX-HEL), whereas late antibodies all displayed IdX-HEL. Furthermore, individual late hybridomas could each remove the entire anti-IdX-HEL activity by absorption, whereas early hybridomas could not. The epitope specificities of the hybridomas in both the early and late populations were heterogenous. We conclude that epitypic specificity in the response to HEL is determined independently from idiotypic specificity and that the predominant idiotype is selected for during the maturation of the anti-lysozyme response.

scholarly journals Murine syngeneic mixed lymphocyte response. I. Target antigens are self Ia molecules

1981 ◽  
Vol 154 (5) ◽  
pp. 1652-1670 ◽  
Author(s):  
LH Glimcher ◽  
DL Longo ◽  
I Green ◽  
RH Schwartz
Keyword(s):  
T Cells ◽  
Culture Conditions ◽  
Primary Response ◽  
Secondary Response ◽  
Mouse Serum ◽  
Lymphocyte Response ◽  
Radiation Induced ◽  
Antigen Presenting

A system has been described that produces a murine syngeneic mixed lymphocyte response (MLR) comparable in magnitude to an allogeneic MLR. The responder cells in these cultures exhibit the classic immunologic characteristics of both memory and specificity. Studies using radiation-induced bone marrow chimeras of F(1) {arrow} parent type indicated that, similar to many other T cell-mediated immune responses, the response of the T lymphocytes in the syngeneic MLR was major histocompatibility complex-restricted and was determined by the environment in which the T cells matured. Using responder T cells from F(1) {arrow} parent chimeras and stimulator cells from H-2 recombinant strains, it was possible to map the genes involved in the stimulation to the K and/or I regions. In addition, blocking studies with monoclonal anti-Ia antibodies suggested that in the B10.A strain the critical molecules were products of both the I-A(k) and I-E(k) subregions. The issue of whether the syngeneic MLR is directed solely at self I-region antigens or whether the response represents proliferation to an unknown antigen in association with self I-region determinants was also addressed. Secondary syngeneic MLR were successfully performed in normal mouse serum and with stimulator cells prepared in the absence of bovine serum albumin to rule out the possibility that xenogeneic serum antigens were involved in the stimulation. The possibility that the syngeneic MLR might represent a secondary response to environmental antigens was eliminated by using germ- free mice as a source of stimulator cells and by demonstrating that spleen cells from unimmunized, fully allogeneic chimeras (B10.A {arrow} B10) could generate a normal syngeneic MLR even though such chimeras could not be primed to respond to any foreign antigens unless supplemented in vivo with a source of antigen-presenting cells syngeneic to the B10 host. The possibility that the syngeneic MLR was a primary response to a foreign antigen was considered unlikely because by using our culture conditions we could not obtain a primary antigen response or a secondary antigen response after in vitro priming to a variety of potent foreign antigens. Finally, the possibility that the syngeneic MLR represents a response to a variety of minor histocompatibility self antigens in association with self Ia molecules was eliminated by showing that the secondary responses to H-2 compatible, non-H-2 different strain (A/J vs. B10.A and C3H, or BALB/c vs. B10.D2 and DBA/2) were comparable to the secondary responses to syngeneic stimulators. Thus, we conclude that the target antigens in the syngeneic MLR are solely determinants on self Ia molecules, although the functionally equivalent possibility of a single, nonpolymorphic, minor self antigen seen in association with self Ia molecules cannot be excluded.

scholarly journals IMMUNOLOGICAL MEMORY IN VITRO

1971 ◽  
Vol 133 (4) ◽  
pp. 846-856 ◽  
Author(s):  
Gordon N. Radcliffe ◽  
Michael A. Axelrad
Keyword(s):  
Spleen Cell ◽  
Primary Response ◽  
Secondary Response ◽  
Spleen Cells ◽  
Sheep Erythrocytes ◽  
Early Primary ◽  
Primary Type ◽  
Type Response

The immune responses to sheep erythrocytes of mouse spleen cell suspensions from immune and nonimmune donors were compared in vitro. In vivo immunity was only transiently reflected in vitro, and 8 wk after in vivo immunization the responses of cultures from immunized and nonimmunized mice were virtually identical. There appeared to be two mechanisms for an antibody response to sheep erythrocytes. The first was responsible for the early primary response and is unmodified in the immune animal though contributing little to subsequent in vivo responses due to its suppressibility by specific antibody. The second was expressed in the in vivo secondary response but not on in vitro challenge of spleen cells from mice immunized many weeks previously; spleen cell cultures from such immune mice, freed from the antibody of the in vivo environment, once again demonstrate a pure primary-type response.

scholarly journals Generation of cytotoxic T lymphocytes in vitro. IV. Functional activation of memory cells in the absence of DNA synthesis.

1975 ◽  
Vol 142 (3) ◽  
pp. 622-636 ◽  
Author(s):  
H R MacDonald ◽  
B Sordat ◽  
J C Cerottini ◽  
K T Brunner
Keyword(s):  
T Lymphocytes ◽  
Dna Synthesis ◽  
Cell Number ◽  
Primary Response ◽  
Precursor Cells ◽  
Lymphoid Cells ◽  
Velocity Sedimentation ◽  
Secondary Response ◽  
Ctl Activity

Re-exposure of day 14 mixed leukocyte culture (MLC) cells to the original stimulating alloantigens (secondary response) has previously been shown to result in significant proliferation and in rapid reappearance of high levels of cytolytic T-lymphocyte (CTL) activity within the next 4 days. Moreover, evidence has been presented that CTL precursor cells in day 14 MLC populations, while they derived from cells were large at peak of the primary response (day 4) were themselves small lymphocytes which developed into large CTL after restimulation. In this study, inhibition of DNA synthesis by cytosine arabinoside (ARA-C) was used to investigate whether CTL formation could be dissociated from proliferation during the secondary response. It was found that within the first 24 h after restimulation (a) CTL activity increased 6-to-20-fold, (b) 60-70% of the small T lymphocytes became medium- to large-sized cells, and (c) both events were independent of DNA synthesis. By using two successive cell separations by velocity sedimentation at unit gravity, before and after stimulation of day 14 MLC cells for 24 h in the presence or absence of ARA-C, direct evidence was obtained that small CTL precursor cells developed into large CTL, irrespective of DNA synthesis. The presence of ARA-C for periods longer than 24 h inhibited any further increase in CTL activity, in contrast to a parallel increase in lytic activity and cell number from day 1 to day 4 in control restimulated cultures. Taken together with the finding that 90% of the medium- and large-sized lymphoid cells in control restimulated cultures underwent DNA synthesis within 24 h, these results thus suggest that during a secondary MLC response there is initially a differentiation step leading to the formation of CTL which, although it can be clearly dissociated from DNA synthesis, is under normal conditions followed by proliferation of these effector cells.

scholarly journals A RECEPTOR FOR ANTIBODY ON B LYMPHOCYTES

1972 ◽  
Vol 135 (3) ◽  
pp. 610-626 ◽  
Author(s):  
A. Basten ◽  
J. F. A. P. Miller ◽  
J. Sprent ◽  
J. Pye
Keyword(s):  
T Cells ◽  
B Cells ◽  
B Lymphocytes ◽  
Antibody Binding ◽  
Lymphoid Cells ◽  
Secondary Response ◽  
Target Cells ◽  
Binding Studies ◽  
Cell Content

Evidence is presented for the existence on all B lymphocytes, but not on T lymphocytes, of a membrane-associated receptor for antibody. The receptor was detected by a radioautographic technique in which lymphoid cells were incubated with antibody followed by the corresponding radioiodinated antigen. The ease with which antibody eluted during washing indicated that the bond between antibody and cell was weak. The formation of an antibody-antigen complex on the cell surface, however, stabilized the bond and permitted accurate quantitation of cells with adherent antibody. The ability of several combinations of antibody and antigen to adhere to the cells demonstrated the nonspecificity of the phenomenon and emphasized the need for care in interpretation of antigen-binding studies particularly when immune cells are being used. The identity of antibody-binding lymphocytes was established by two different approaches. In the first, mouse lymphocyte populations greatly enriched for either T cells or B cells were examined. Their T cell content was assessed by means of well-established markers such as the θ C3H isoantigen. When this was compared with the number of antibody-binding cells, an inverse relationship was obtained in each instance; thus almost all thoracic duct cells from athymic mice labeled with an immune complex although none were θ positive. The striking reduction in antibody-binding cells observed in bursectomized chickens provided a second and independent line of evidence suggesting that B cells, not T cells, bind antibody. The ability of B cells from primed animals to bind antibody in vivo made it important to test whether this phenomenon was related to the carriage of immunological memory. No correlation was, however, found between membrane-bound antibody and memory. It was proposed that the existence of a receptor of this kind may provide a rational explanation for antibody-dependent killing of target cells and may prove of importance in antigen concentration particularly during the secondary response.

scholarly journals GAMMA GLOBULIN AND ANTIBODY FORMATION IN VITRO

1967 ◽  
Vol 125 (1) ◽  
pp. 33-44 ◽  
Author(s):  
Vera J. Stecher ◽  
G. Jeanette Thorbecke
Keyword(s):  
Antibody Formation ◽  
Primary Response ◽  
Secondary Response ◽  
Detectable Effect ◽  
Complete Suppression ◽  
Similar Time ◽  
X Irradiation ◽  
Early Radiation

The present studies have shown that the influence of X-irradiation on the secondary antibody response in vitro is remarkably similar to its effect on the primary response in vivo. When sensitized tissue was first irradiated and then reexposed to antigen, the duration of the interval between irradiation and antigen addition determined the degree of inhibition of the secondary response obtained. A delay of 12 hr resulted in stronger inhibition than a delay of 6 hr, and an interval of 24 hr before reexposure to antigen caused complete suppression of antibody production to diphtheria toxoid and almost complete suppression when sheep RBC were used as the antigen. Induction of the secondary response in rabbit lymph node tissue in vitro followed by exposure to X-irradiation, revealed that immediate exposure to irradiation after antigen produced stronger inhibition of the subsequent response than irradiation on days 2–3. Irradiation on day 6 had no detectable effect. The effectiveness of the early radiation is probably due to prevention of the proliferation of the antibody-forming cells. BUDR was found to be effective at similar time periods as X-irradiation, whereas colchicine could still stop antibody formation when added late during the secondary response in vitro. It was noted that lymph nodes from some BSA-sensitized rabbits as late as 18 months after sensitization gave a response indistinguishable from a typical secondary response, even when not reexposed to antigen.

scholarly journals Duration of the initial TCR stimulus controls the magnitude but not functionality of the CD8+ T cell response

2006 ◽  
Vol 203 (9) ◽  
pp. 2135-2143 ◽  
Author(s):  
Martin Prlic ◽  
Gabriela Hernandez-Hoyos ◽  
Michael J. Bevan
Keyword(s):  
T Cells ◽  
Diphtheria Toxin ◽  
Clonal Expansion ◽  
Primary Response ◽  
T Cell Response ◽  
Secondary Response ◽  
Memory Cells ◽  
Effector Cells

CD8+ T cells only require a brief stimulation with antigen in vitro to divide and differentiate into effector and memory cells upon transfer in vivo. The efficiency of clonal expansion and the functional characteristics of memory cells derived from briefly stimulated cells are poorly defined. We developed a system that allowed us to examine programming entirely in vivo. This was achieved by rapidly killing peptide-pulsed DCs carrying a diphtheria toxin receptor transgene with timed injections of diphtheria toxin without altering the course of an accompanying infection. The magnitude of clonal expansion, but not the functionality of the effector cells, correlated directly with the duration of antigen exposure. Furthermore, memory T cells were capable of mounting a secondary response, regardless of the length of antigen encounter during the primary response. These results indicate that the duration of initial antigen encounter influences the magnitude of the primary response, but does not program responsiveness during the secondary challenge.

scholarly journals In vivo modulation of CD1 and MHC class II expression by sheep afferent lymph dendritic cells. Comparison of primary and secondary immune responses.

1989 ◽  
Vol 170 (4) ◽  
pp. 1303-1318 ◽  
Author(s):  
J Hopkins ◽  
B M Dutia ◽  
R Bujdoso ◽  
I McConnell
Keyword(s):  
T Cells ◽  
Dendritic Cells ◽  
Immune Responses ◽  
Cell Lines ◽  
Mhc Class Ii ◽  
Class Ii ◽  
Primary Response ◽  
Secondary Response ◽  
Afferent Lymph

The experiments described in this article characterize the phenotypic and functional changes in afferent lymph cell populations that occur as a result of in vivo immune stimulation. During the primary immune response (in antigen-naive sheep) there are very transient increases in level of CD1 expression by subpopulations of dendritic cells (DC) but no alterations in cell kinetics or MHC class II expression. In contrast, secondary antigenic challenge (in primed sheep) into the drainage area of an afferent lymphatic causes profound changes in the cell output, characterized by a greater than threefold drop in total cell output on days 1-3 followed by an approximate fivefold rise on day 5. There is also a substantial increase in both the proportion of MHC class II-positive T lymphocytes (from 28 to 54%) and in the quantitative expression of class II by both DC and lymphocytes. Class II expression by DC increases five- to sixfold by day 5, while the level of expression of class II on lymphocytes approximately doubles. The increase in CD1 expression during the secondary response is more prolonged than during the primary response, being detectable between days 2 and 6 after challenge. The rise in class II affects the whole DC population, in contrast to CD1 where the increase affects only a subpopulation of cells. In terms of functional properties, afferent lymph DC isolated during a primary response show no alteration of their activity, whereas DC taken 4-5 d after secondary challenge are up to fivefold more active in their ability to present soluble antigen to primed autologous T cells and to antigen-specific cell lines as well as to stimulate in the MLR. The relative expression of class II correlates temporally with an increased capacity of DC to present antigen. Monoclonal anti-class II antibodies totally inhibit the in vitro assays but anti-CD1 antibodies have no effect. The previous paper has demonstrated that afferent DC can associate with antigen in vivo and can present that antigen to antigen-specific T cells. This article extends our knowledge of DC biology and demonstrates that DC, activated during secondary in vivo immune responses, have an enhanced ability to present an antigen, unrelated to that used for challenge, to specific T cell lines. This enhancement correlates directly with quantitative variation of expressed class II and not CD1 and suggests that this variation in class II expression plays a physiological role in in vivo immune regulation.

The Effect of Barbituric Acid Derivatives on Platelet Function in Vitro and in Vivo

1973 ◽  
Vol 30 (02) ◽  
pp. 315-326
Author(s):  
J. Heinz Joist ◽  
Jean-Pierre Cazenave ◽  
J. Fraser Mustard
Keyword(s):  
Platelet Aggregation ◽  
Platelet Function ◽  
Barbituric Acid ◽  
Platelet Rich Plasma ◽  
Inhibitory Effect ◽  
Primary Response ◽  
Sodium Pentobarbital ◽  
Barbituric Acid Derivatives

SummarySodium pentobarbital (SPB) and three other barbituric acid derivatives were found to inhibit platelet function in vitro. SPB had no effect on the primary response to ADP of platelets in platelet-rich plasma (PRP) or washed platelets but inhibited secondary aggregation induced by ADP in human PRP. The drug inhibited both phases of aggregation induced by epinephrine. SPB suppressed aggregation and the release reaction induced by collagen or low concentrations of thrombin, and platelet adherence to collagen-coated glass tubes. The inhibition by SPB of platelet aggregation was readily reversible and isotopically labeled SPB did not become firmly bound to platelets. No inhibitory effect on platelet aggregation induced by ADP, collagen, or thrombin could be detected in PRP obtained from rabbits after induction of SPB-anesthesia.

scholarly journals POS0461 RESPONSE TO BIOLOGIC THERAPY IN RHEUMATOID ARTHRITIS: RETHINKING OUR CLASSIFICATION

2021 ◽  
Vol 80 (Suppl 1) ◽  
pp. 462.1-462
Author(s):  
E. Vallejo-Yagüe ◽  
S. Kandhasamy ◽  
E. Keystone ◽  
A. Finckh ◽  
R. Micheroli ◽  
...  
Keyword(s):  
Treatment Response ◽  
Real World ◽  
Observational Studies ◽  
Initial Response ◽  
Primary Response ◽  
Sustained Response ◽  
Secondary Response ◽  
Real World Data ◽  
World Data ◽  
Secondary Failure

Background:In rheumatoid arthritis (RA), primary failure with biologic treatment may be understood as lack of initial clinical response, while secondary failure would be loss of effectiveness after an initial response. Despite these clinical concepts, there is no unifying operational definition of primary and secondary non-response to RA treatment in observational studies using real-world data. On top of data-driven challenges, when conceptualizing secondary non-responders, it is unclear if the mechanism behind loss of effectiveness after a brief initial response is similar to loss of effectiveness after previous benefit sustained over time.Objectives:This viewpoint aims to motivate discussion on how to define primary and secondary non-response in observational studies. Ultimately, we aim to trigger expert committees to develop standard terminology for these concepts.Methods:We discuss different methodologies for defining primary and secondary non-response in observational studies. To do so, we shortly overview challenges characteristic of performing observational studies in real-world data, and subsequently, we conceptualize whether treatment response should be a dichotomous classification (Primary response/non-response; Secondary response/non-response), or whether one should consider three response categories (Primary response/non-response; Primary sustained/non-sustained response; Secondary response/non-response).Results:RA or biologic registries are a common data source for studying treatment response in real-world data. While registries include disease-specific variables to assess disease progression, missing data, loss of follow-up, and visits restricted to the year or mid-year visit may present a challenge. We believe there is a general agreement to assess primary response within the first 6 month of treatment. However, conceptualizing secondary non-response, one could wonder if a patient with brief initial response and immediate loss of it should belong to the same response category as a patient who relapses after a period of prior benefit that was sustained over time. Until this concern is clarified, we recommend considering a period of sustained response as a pre-requisite for secondary failure. This would result in the following three categories: a) Primary non-response: Lack of response within the first 6 months of treatment; b) Primary sustained response: Maintenance of a positive effectiveness outcome for at least the first 12 months since treatment start; c) Secondary non-response: Loss of effectiveness after achieved primary sustained response. Figure 1 illustrates this classification through a decision tree. Since the underlying mechanisms for treatment failure may differ among the above-mentioned categories, we recommend to use the three-category classification. However, since this may pose additional methodological challenges in real-world data, optionally, a dichotomous 12-month time-point may be used to assess secondary non-response (unfavourable outcome after 12-months) in comparison to primary non-response or non-sustained response (unfavourable outcome within the first 12-months). Similarly, to study primary response, the solely 6-month timepoint may be used.Conclusion:A unified operational definition of treatment response will minimize heterogeneity among observational studies and help improve the ability to draw cross-study comparisons, which we believe would be of particular interest when identifying predictors of treatment failure. Thus, we hope to open the room for discussion and encourage expert committees to work towards a common approach to assess treatment primary and secondary non-response in RA in observational studies.Disclosure of Interests:Enriqueta Vallejo-Yagüe: None declared, Sreemanjari Kandhasamy: None declared, Edward Keystone Speakers bureau: Amgen, AbbVie, F. Hoffmann-La Roche Inc., Janssen Inc., Merck, Novartis, Pfizer Pharmaceuticals, Sanofi Genzyme, Consultant of: AbbVie, Amgen, Bristol-Myers Squibb Company, Celltrion, Myriad Autoimmune, F. Hoffmann-La Roche Inc, Gilead, Janssen Inc, Lilly Pharmaceuticals, Merck, Pfizer Pharmaceuticals, Sandoz, Sanofi-Genzyme, Samsung Bioepsis, Grant/research support from: Amgen, Merck, Pfizer Pharmaceuticals, PuraPharm, Axel Finckh Speakers bureau: Pfizer, Eli-Lilly, Paid instructor for: Pfizer, Eli-Lilly, Consultant of: AbbVie, AB2Bio, BMS, Gilead, Pfizer, Viatris, Grant/research support from: Pfizer, BMS, Novartis, Raphael Micheroli Consultant of: Gilead, Eli-Lilly, Pfizer and Abbvie, Andrea Michelle Burden: None declared

Influence of flumequine on in vivo mitogen responses of European eel (Anguilla anguilla L., 1758) lymphoid cells

1995 ◽  
Vol 47 (1-2) ◽  
pp. 143-152 ◽  
Author(s):  
M.H.T. van der Heijden ◽  
G.H.R. Booms ◽  
M.W.T. Tanck ◽  
J.H.W.M. Rombout ◽  
J.H. Boon
Keyword(s):  
Anguilla Anguilla ◽  
Lymphoid Cells ◽  
European Eel
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