bluuebunny/crossref_metadata_2025_split huggingface dataset:
IN VIVO REQUIREMENT FOR A RADIATION-RESISTANT CELL IN THE IMMUNE RESPONSE TO SHEEP ERYTHROCYTES
Authors: Gorczynski R. M. , Miller R. G. , Phillips R. A. 
Published: June 2004

Experiments have been done to establish whether the radiation-resistant or A cell has a specific function in the initiation of an immune response in mice to sheep erythrocytes (SRBC). All previous demonstrations using accessory (A) cells have involved in vitro assays and are possibly explainable as tissue culture artifacts. If A cells are essential, it should be possible to demonstrate their requirement in vivo. Therefore we first established such conditions. Two methods were found for creating an A-cell deficiency in vivo: (a) A cells disappear gradually from the spleens of irradiated mice, presumably by migration since A-cell function was shown not to be decreased by irradiation. If 3 days elapse between irradiation and transplantation of mixtures of bone marrow and thymus cells (which provide B and T but few A cells), the usual synergistic response does not occur. Addition of large numbers of freshly irradiated spleen cells to the mixture of bone marrow and thymus completely restores the immune response. (b) Injection of 1010 horse erythrocytes into mice suppresses A-cell activity in these mice 24 hr later; a much reduced response to SRBC is obtained when they are given at this time. The response can be partially restored if irradiated spleen cells are given with the SRBC. This observation formed the basis for a quantitative in vivo assay for A cells in which the magnitude of restoration by various suspensions of irradiated cells was used to estimate the A-cell activity of that suspension. A quantitative in vitro assay for A cells was also developed. It was essential for this assay that the total cell number, B-cell number, and T-cell number be kept constant and that only the number of A cells be allowed to vary. Only under these conditions was the response a linear function of the number of A cells added.
If the in vivo and in vitro assays are detecting the same class of radiation-resistant cells, the physical properties of the cells active in each assay should be identical. Spleen cells were separated on the basis of both density and sedimentation velocity. Fractions from both separation methods were tested for their content of A cells using both the in vivo and in vitro assays. The density and sedimentation profiles of A cells were similar in both assays.
The demonstration that a radiation-resistant cell is required in vivo and that this cell has properties identical to the radiation-resistant cell required in vitro indicates that this cell (the A cell) is directly involved in the initiation of an immune response to erythrocyte antigens.
ELECTRON MICROSCOPIC LOCALIZATION OF IMMUNOGLOBULIN E ON THE SURFACE MEMBRANE OF HUMAN BASOPHILS
Authors: Sullivan Albert L. , Grimley Philip M. , Metzger Henry 
Published: June 2004

We have examined human leukocyte preparations for the presence of surface-bound IgE by electron microscopy. Basophil-enriched leukocytes were reacted with burro anti-IgE, a hybrid antibody to burro IgG and ferritin, and ferritin, with or without prior incubation of the cells with an IgE myeloma protein.
In the absence of preincubation with IgE small amounts of ferritin were fixed to the surface of basophils but on no other cells. When cells were preincubated with IgE the amount of ferritin fixation on the basophils was markedly increased and a small amount of ferritin was also bound to platelets but again to no other leukocytes. The distribution of ferritin on the basophil surface appeared dependent upon the temperature at which the cells were kept during and after reaction with the various reagents. Basophil sections from cells kept at 0°C had ferritin bound to the surface membrane in patches distributed around the entire circumference. Basophil sections from cells prepared at room temperature had ferritin distributed assymetrically covering a surface membrane segment one-fifth to one-half of the circumference.
In control studies in which monomeric IgG was substituted for the IgE and burro anti-IgG was used instead of burro anti-IgE, no cellular fixation of ferritin was observed.
ANTIGEN MODULATION OF THE IMMUNE RESPONSE
Authors: Feldbush T. L. , Gowans J. L. 
Published: June 2004

Secondary immune responsiveness to dinitrophenylated bovine gamma globulin (DNP-BGG) was transferred to heavily irradiated rats by means of small lymphocytes from the thoracic duct of immunized syngeneic donors. Affinity of the antibody produced by the adoptive recipients when challenged immediately was the same as that seen in immunized controls and cell donors, suggesting that the performance of lymphocytes in the thoracic duct of immunized rats provide an accurate measure of the immunologic history of memory cells both in the intact animal and the lymphocyte-depleted donor. The relevance of this to cell cooperation in the production of antibody to hapten-protein complexes is discussed.
Direct evidence on antigen modulation of the immune response was also obtained. When immune thoracic duct lymphocytes were transferred to adoptive recipients and challenged either immediately or after a delay of 6 wk, it was found that, although the amount of antibody decreased with this delay in challenge, the affinity remained constant. Thus it would seem that in control rats, the increase in the affinity of antibody with time after immunization is, in fact, due to the selection of new populations of cells by the progressively waning concentration of antigen.
PECULIAR IMMUNOBIOLOGY OF BONE MARROW ALLOGRAFTS
Authors: Cudkowicz Gustavo , Bennett Michael 
Published: June 2004

F1 hybrid mice are capable of rejecting inbred parental strain bone marrow grafts after a single lethal exposure to X-rays. The incompatibility is genetically controlled by the Hybrid-histocompatibility-1 (Hh-1) locus in or near the D end of the Histocompatibility-2 (H-2) region. The onset of parental graft rejection begins 9–12 hr after transplantation and is completed by 24 hr. Maturation of hybrid resistance does not occur until the 22nd day of life. In adults, the resistance to parental marrow grafts can be temporarily abrogated or weakened by administration of cyclophosphamide or dead cultures of Corynebacterium parvum, acute supralethal exposures to radiation, or by split-dose irradiation with 6–37-day intervals.
Parental marrow grafts elicit a transplantation reaction in irradiated F1 mice which is indistinguishable from that elicited in irradiated allogeneic (H-2-incompatible) hosts. Because of this immunogenetic similarity, the following question is raised: are the same or different alloantigens responsible for rejection of parental and allogeneic marrow grafts? In the first case, Hh-1 alleles would be recessive determinants of tissue-specific transplantation antigens, whereas in the second case they would be the determinants of parental- and tissue-specific antigens subject to genetic suppression in Hh-1 heterozygotes. Although the available evidence is not conclusive in excluding one of the two possibilities, it favors the concept that allograft reactivity to hemopoietic cells is elicited by recessive tissue-specific antigens.
GENETIC CONTROL OF THE IMMUNE RESPONSE
Authors: Mitchell Graham F. , Grumet F. Carl , McDevitt Hugh O. 
Published: June 2004

The effect of thymectomy on the genetically controlled murine immune response-1 (Ir-1) to the synthetic polypeptide poly-L(Tyr, Glu)-poly-D, L-Ala--poly-L-Lys [(T, G)-A--L] was studied with both aqueous and adjuvant immunization regimens. Adult thymectomy (combined with irradiation and bone marrow transfusion) did not affect the aqueous antigen-induced (IgM) primary response of either high or low responder mice, but did ablate the (IgG) secondary or tertiary response, a response which is restricted to the high responder strains. Adult thymectomy also blocked the normal high response to (T,G)-A--L in Freund's adjuvant in high responder mice and the high response to methylated bovine serum albumin (MBSA)-(T,G)-A--L in low responder mice. Neonatal thymectomy was also effective in blocking the response to (T, G)-A--L in Freund's adjuvant in high responder mice.
These data are consistent with the concept that the Ir-1 gene effect is mediated via thymus cell interaction with antigen and with "B"-cells during the time of induction of IgG antibody formation.
THYMOCYTES FROM MICE IMMUNIZED AGAINST AN ALLOGRAFT RENDER BONE-MARROW CELLS SPECIFICALLY CYTOTOXIC
Authors: Grant C. K. , Currie G. A. , Alexander P. 
Published: June 2004

Thymocytes from C57BL mice immunized with the DBA/2 lymphoma L5178Y exert in vitro an immunologically specific cytotoxic action against the target cells in the presence of bone-marrow cells. Neither the nonimmune bone marrow nor the immune thymocytes are by themselves cytotoxic. The cells in the bone marrow which take part in the cytotoxic action adhere to glass and are sensitive to anti-macrophage serum. These bone-marrow cells can also be rendered specifically cytotoxic by exposure to the supernatant obtained from a culture of immune thymocytes with the specific target cells. The thymocytes before they are confronted with the specific target cells are very radiosensitive; however, on coming into contact with the target cells, an immunologically specific increase in RNA synthesis occurs and thereafter the thymocytes' capacity to render bone-marrow cells cytotoxic is relatively radioresistant.
Two classes of immune lymphocytes occur in mice immunized with allogeneic cells, those that are capable of killing target cells directly and those that produce a factor capable of rendering macrophages (or monocytes) specifically cytotoxic. In the thymus of immune animals only the latter are found while both categories are present in the spleen and lymph nodes of immune animals.
IMMUNE RESPONSE TO CHEMICALLY MODIFIED FLAGELLIN
Authors: Parish C. R. , Liew F. Y. 
Published: June 2004

High and low zone antibody tolerance to bacterial flagellin can be induced in adult strain W Wistar rats by multiple injections of a cyanogen bromide (CNBr) digest of flagellin at two widely spaced dose levels. Intermediate doses of the CNBr digest produce enhanced antibody titers to flagellin rather than antibody tolerance. Studies reported in this paper revealed that both high and low zone antibody tolerance to flagellin were accompanied by heightened levels of delayed-type hypersensitivity. Conversely, when enhancement of the antibody response occurred, suppression of delayed hypersensitivity was observed.
This inverse relationship between humoral and cell-mediated immunity was very striking in strain W Wistar rats but was not quite so clear-cut in another strain of Wistar rats (strain J). Strain J rats were resistant to the induction of antibody tolerance and gave higher immunological responses to flagellin than strain W animals. In addition, it was observed that, in contrast to adult tolerance, administration of the CNBr digest to neonatal rats induced complete tolerance at the level of both humoral and cell-mediated immunity.
These findings were discussed in the light of earlier studies with flagellin and provide further evidence for a previously described hypothesis.
STUDIES ON ANTIBODY AFFINITY AT THE CELLULAR LEVEL
Authors: Andersson Birger 
Published: June 2004

Heterogeneity with regard to affinity of anti-hapten antibody was demonstrated at the cellular level in mice. The heterogeneity was shown at the level of single antibody-forming cells using hapten inhibition of hemolytic antibody plaque formation as a measure of affinity. The affinity increased with time after immunization. A high antigen dose initially resulted in relatively low affinity antibody production as compared to the affinity of the antibody production in animals immunized with a low dose.
Affinity specialization of immunological memory cells was demonstrated, since it was possible to specifically fractionate such cells with regard to affinity on hapten-protein-coated plastic bead columns. High affinity memory cells showed a higher tendency to become retained in the columns than did low affinity memory cells.
The data in a direct way demonstrate that memory cells carrying membrane-associated receptors of a certain affinity for the antigen are determined to release antibody of a similar affinity after stimulation with antigen.
QUANTITATIVE FEATURES OF A SANDWICH RADIOIMMUNOLABELING TECHNIQUE FOR LYMPHOCYTE SURFACE RECEPTORS
Authors: Nossal G. J. V. , Warner N. L. , Lewis Heather , Sprent J. 
Published: June 2004

The present study was designed to devise and characterize an indirect or sandwich radioimmunolabeling technique for the study of lymphocyte surface receptors of immunoglobulin nature. Mouse lymphocytes from various sources were treated by the method of Shortman et al. to remove debris and damaged cells. This was an important preliminary step, as without it, little meaning could be attached to bulk scintillation counting of labeled cell suspensions, in view of the marked tendency of dead or damaged cells to adsorb protein nonspecifically. Next, cells were reacted at 0°C for 30 min with graded dilutions of unlabeled rabbit antisera against defined mouse Ig chains. After washing, the cells were reacted with a sheep anti-rabbit globulin reagent labeled with 125I, again at graded concentrations. After further washing, lymphocyte labeling was quantitated by both bulk scintillation counting and radioautography.
Conditions were defined in which nonthymus-derived cells (B cells) but not thymus-derived cells (T cells) could be labeled. Most B cells displayed κ- and µ-chains on their surface, but some also displayed α- and γ2-chains, though in smaller amounts. When the concentration of both the first and the second reagents were raised considerably, conditions were defined under which virtually all T cells could be labeled by polyvalent antiglobulin sera, anti-κ sera, or, with more difficulty, by anti-µ sera. A large series of control experiments confirmed the serologic specificity of this labeling. It was shown that under equivalent conditions, B cells bind 100–400 times more antiglobulin than do T cells.
The theoretical implications of the results are briefly discussed. It is argued that the sandwich approach offers certain technical advantages over direct labeling procedures for further analyses of T cell receptors and for studies of receptor metabolism.
MOLECULAR ANALYSIS OF THE MEMBRANE ATTACK MECHANISM OF COMPLEMENT
Authors: Kolb William P. , Haxby James A. , Arroyave Carlos M. , Müller-Eberhard Hans J. 
Published: June 2004

The molecular arrangement of the membrane attack mechanism of complement was explored. The molar ratios of the components within the C5-9 assembly on the target cell surface were determined using human complement proteins in highly purified and radiolabeled form. With the aid of monospecific complement antisera it was possible to probe the spatial relationships between the components of the assembly.
C5 and C6, in the presence of C7, were bound to EAC1-3 in equimolar quantities irrespective of the amounts and the relative proportions of C5, C6, and C7 offered. The amount of C8 bound to EAC1-7 increased with input and at saturation of all C8 binding sites the molar ratio of bound C8/bound C5 approached 1.0. Uptake of C9 by EAC1-8 increased with input and at saturation of all C9 binding sites the molar ratio of bound C9/bound C8 became 6.0. However, calculations suggest that the binding of three C9 molecules to one C8 molecule is sufficient to achieve a full hemolytic effect. Evidence was obtained indicating that binding and hemolytic function of C9 depends upon cooperative interaction of multiple C9 molecules.
Binding of C8 to EAC1-7 and the generation of hemolytic C8 sites were inhibited by antibody to either C5, C6, or C7. Uptake of C9 by EAC1-8 and the generation of hemolytic C9 sites were strongly inhibited by anti-C8 and to a lesser degree by anti-C5. Binding of C9 (but not hemolysis) was also reduced by antibody to C6 or C7.
The data are consistent with the concept that the fully assembled membrane attack mechanism of complement consists of a decamolecular complex: a trimolecular arrangement composed of C5, C6, and C7 forms the binding site for one C8 molecule which in turn furnishes binding sites for six C9 molecules, saturation of three sites apparently being sufficient for expression of full cytolytic activity of the complex. This work made it possible to design a simple molecular model.
RELATIONSHIP OF MIXED LYMPHOCYTE CULTURE RESPONSE TO HL-A HISTOCOMPATIBILITY ANTIGENS
Authors: Thompson John S. , Parmely Michael J. , Flink Ronald J. , Canady Marilyn S. , Severson Charles D. 
Published: June 2004

The influence of varying degrees of incompatibility for HL-A antigens on one-way mixed lymphocyte cultures (MLC) has been investigated. Reactions have been compared to a simple expression of HL-A antigens, allele compatibility, and a proposal considering the potential influence of antigen matching in relationship to allele compatibility.
As expected, HL-A compatibility was associated with nonstimulated cultures, but significant correlation was not observed when incompatibility was expressed in terms of HL-A antigen or allele mismatching.
When the relationship of both was considered, however, a second distinctive group was demonstrated that shared one allele plus one antigen of the second allele. Within this group no stimulation, even with augmented culture conditions, was observed in some families. Employing these same criteria, there was no significant difference in the MLC response in those groups that were incompatible for both alleles regardless of the number of matched antigens or the group that shared an allele but differed by both antigens of the second allele.
These results support the concept of an intimate relationship between the loci coding for HL-A antigens and mixed culture reactions. They suggest that HL-A haplotype incompatibility acting as a unit is the primary stimulus of the MLC response, and that the immunogenicity of the haplotype also relates to whether or not one antigen is common to the stimulating and responding cell.
A RECEPTOR FOR ANTIBODY ON B LYMPHOCYTES
Authors: Basten A. , Miller J. F. A. P. , Sprent J. , Pye J. 
Published: June 2004

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.
A RECEPTOR FOR ANTIBODY ON B LYMPHOCYTES
Authors: Basten A. , Warner N. L. , Mandel T. 
Published: June 2004

Binding of antibody to the surface of B lymphocytes was shown to involve the Fc piece of the immunoglobulin molecule. This property was not shared equally by all immunoglobulin classes as revealed by direct binding and inhibition studies. Total IgG globulin was found to label cells more heavily than IgM, and IgG1-containing fractions more heavily than IgG2 fractions lacking IgG1. The ability of various purified myeloma proteins to inhibit attachment of antibody to B cells was examined. Pretreatment of B cells with excess IgG2a, IgA, or light chain proteins failed to inhibit, whereas IgG1 proteins and to a lesser extent Ig2b and IgM proteins at the same concentrations did so. At lower protein concentrations, IgG1 myeloma protein alone retained the capacity to inhibit binding. The conclusion was reached that the receptor on B cells for antibody has a marked predilection for the IgG1 class. Although IgM and IgG2b antibody may bind, they do so with lower avidity and probably in insignificant amounts if IgG1 antibody is present in excess.
No evidence was found to implicate complement in the binding process. For example, heat-inactivated sera at high dilution retained the ability to label B cells, while the use of purified low molecular weight anticomplementary factor, a potent inhibitor of C'3, did not interfere with the formation of the bond between antibody and cell surface.
The failure of anti-mouse immunoglobulin F(ab)'2 fragments to prevent access of antibody to B cells implied that the antibody-binding receptor and antigen-binding (immunoglobulin) receptor are discrete entities on the B cell membrane. Despite this, a marked similarity between their surface distribution was observed on electron microscopy.
The antibody-binding receptor was shown to be a marker for mature B cells. It did not appear to be present on hematopoietic precursor stem cells and was lost during differentiation to antibody-forming cells.
GRANULATION TISSUE AS A CONTRACTILE ORGAN
Authors: Gabbiani G. , Hirschel B. J. , Ryan G. B. , Statkov P. R. , Majno G. 
Published: June 2004

Contracting granulation tissues contain fibroblasts that develop characteristics typical of smooth muscle: (a) They contain an extensive cytoplasmic fibrillar system. (b) They show immunofluorescent labeling of their cytoplasm with human anti-smooth muscle serum. (c) The nuclei show complicated folds and indentations, indicative of cellular contraction. (d) There are cell-to-cell and cell-to-stroma attachments. (e) It is possible to extract similar quantities of actomyosin (having the same adenosine triphosphatase activity) from granulation tissue and from pregnant rat uterus. (f) Strips of granulation tissue, when tested pharmacologically in vitro, behave similarly to smooth muscle.
All these data support the view that, under certain conditions, fibroblasts can differentiate into a cell type structurally and functionally similar to smooth muscle and that this cell, the "myo-fibroblast," plays an important role in connective tissue contraction.