bluuebunny/crossref_metadata_2025 huggingface dataset:
Idiotypic determinants on T-cell subpopulations.
Authors: Binz H , Frischknecht H , Shen F W , Wigzell H
Published: June 2004

Killer T cells with specificity for major histocompatibility antigens have been shown in mice and rats to display idiotypic receptors allowing the lysis of such cells at the effector phase by anti-idiotypic antibodies and complement. A comparison was made between idiotypes displayed by Lyt-1-2+3+ and Lyt-1+2-3- T blasts, generated in the same mixed leucocyte culture (MLC), across an entire H-2 locus barrier. This was done by absorption of anti-idiotypic antibodies with respective T blasts, followed by estimation of the ability of the absorbed antiserum to inhibit MLC or killer T-cell function. Further, the capacity of Lyt-purified, MLC-generated T blasts to provoke specific unresponsiveness via anti-idiotypic immunity in syngeneic recipients was analyzed. Taken together, the results demonstrate that Lyt-1+2-3- T blasts responsible for the major part of MLC proliferation have distincly different idiotypes from those on the Lyt 1-2+3+ killer T cells. That the idiotypes on the killer T-cell presursors can serve as triggering sites for induction of effector T-cell function was then suggested by experiments with Lyt-1-2+3+-purified, normal T cells as precursor cells in vitro. The fact that autoanti-idiotypic antibodies may circumvent the need for helper Lyt-1+2-3- T cells in the generation of allospecific killer T cells indicates that the former cells may normally function partly via such anti-idiotypic reactions.
Distinct functions of monoclonal IgG antibody depend on antigen-site specificities.
Authors: Schalch W , Wright J K , Rodkey L S , Braun D G
Published: June 2004

Intraveneous hyperimmunization of selectivity bred rabbits with streptococcal group A-variant vaccines elicits antibody responses of restricted heterogeneity at high antibody levels. All antisera contain two functionally distinct antibody populations, which can be isolated in single-band purity upon analytical isoelectric focusing. Typical examples of these two kinds of single-band antibodies were investigated in great detail for several parameters by a variety of methods. 85--99% of the streptococcal group A-variant polysaccharide (Av-CHO)-specific antibody in the antisera does not precipitate the isolated 5,000 daltons poly-L-rhamnose antigen, neither agglutinates nor lyses in the presence of complement Av-CHO-coated sheep erythrocytes (SRBC), binds the radio-labeled Av-CHO with an association constant in the ragne of 10(5)--10(6) M-1, and is of terminal specificity (nonreducing end) for the linear Av-CHO. In contrast, the minor fraction of Av-CHO-specific antibody (1--15%) does precipitate the linear Av-CHO, both agglutinates and lyses Av-CHO-coated SRBC in the presence of complement, has an affinity range of 10(8)--10(9) M-1, and is of internal specificity for the Av-CHO. The antigenic determinants of the Av-CHO for the antibodies are nonoverlapping, only one Fab of the low affinity antibody can be bound whereas four Fab of the high affinity antibody are accommodated. Hence, the determinant specificity explains the functional differences observed, for there is no indication of subclass differences. A mechanistic model of the A-variant carbohydrate presentation on the vaccine appears to account best for the unbalanced levels of low and high affinity antibody.
Normal functional characteristics of cultured human promyelocytic leukemia cells (HL-60) after induction of differentiation by dimethylsulfoxide.
Authors: Collins S J , Ruscetti F W , Gallagher R E , Gallo R C
Published: June 2004

The HL-60 human promyelocytic leukemia cell line can be induced to terminally differentiate to mature myeloid cells sharing a number of functional characteristics with normal granulocytes including response to chemoattractants, development of complement receptors, phagocytosis, superoxide production, and nitroblue tetrazolium dye reduction. Hence the Me2SO-induced HL-60 cells provide a unique in vitro model for studying various important aspects of human myeloid cell differentiation.
Structural studies on the murine Ia alloantigens. V. Evidence that the structural gene for the I-E/C beta polypeptide is encoded within the I-A subregion.
Authors: Cook R G , Vitetta E S , Uhr J W , Capra J D
Published: June 2004

The E/C alpha- and beta-subunits of intra-I-region recombinants were analyzed for primary structural variation by comparative tryptic peptide mapping. The E/C alpha-polypeptides from B10.A, B10.A (3R) and B10.A (5R) showed complete coincident elution of peptides; the E/C beta-chains from B10.A and 3R (or 5R) were approximately 40% different. This suggests that the structural gene for the E/C beta-polypeptide is within the I-A subregion.
Activation of macrophages in vivo and in vitro. Correlation between hydrogen peroxide release and killing of Trypanosoma cruzi.
Authors: Nathan C , Nogueira N , Juangbhanich C , Ellis J , Cohn Z
Published: June 2004

As reported previously, mouse peritoneal macrophages could be activated to kill intracellular trypomastigotes of Trypanosoma cruzi, the agent of Chagas' disease, in either of two ways: by immunizing and boosting the mice (3), or by culturing resident or inflammatory macrophages in spleen cell factor(s) (SCF) in vitro (2). Macrophages activated in vivo became less trypanocidal with time in culture, and cells activated in vitro lost trypanocidal capacity when CSF was removed (2). In the present study, the ability of macrophages to release H2O2 in response to phorbol myristate acetate (PMA) could be induced in vivo and in vitro, and reversed in vitro, in a manner correlating closely with changes in trypanocidal activity. Macrophages could be activated in vitro with SCF in a time-dependent and dose-dependent fashion, so that they released as much H2O2 as macrophages activated in vivo. The sensitivity of epimastigotes and trypomastigotes to enzymatically generated H2O2 suggested that the generation of H2O2 by activated macrophages could be plausible explanation for their trypanocidal activity. Of the biochemical correlates of macrophage activation reported to date, increased ability to release H2O2 seems most closely allied to enhanced capacity to kill an intracellular pathogen.
Mechanisms of regulation of cell-mediated immunity. III. The characterization of azobenzenearsonate-specific suppressor T-cell-derived-suppressor factors.
Authors: Greene M I , Bach B A , Benacerraf B
Published: June 2004

Delayed type hypersensitivity to the hapten azobenzenearsonate (ABA) can be induced and suppressed by the administration of hapten-coupled syngeneic spleen cells by the appropriate route. Suppressor T cells stimulated by the intravenous administration of ABA-coupled spleen cells have been shown to produce a discrete subcellular factor(s) which is capable of suppressing delayed type hypersensitivity to azobenzenearsonate in the mouse. Such suppressor factors may be produced by the mechanical disruption of suppressor cells or by placing such suppressor cells in culture for 24 h. The suppressor factor(s) (SF) derived from ABA-specific suppressor cells exhibit biological specificity for the suppression of ABA delayed type hypersensitivity (DTH), but not trinitro-phenyl DTH, as well as the capacity to bind to ABA immunoadsorbents. Passage of suppressor factor(s) over reverse immunoadsorbents utilizing a rabbit anti-mouse F(ab')2 antiserum demonstrated that the antigen-specific T-cell derived SF does not bear conventional immunoglobulin markers. The suppressor factor(s) are not immunoglobulin molecules was further demonstrated by the inability of anti-ABA antibodies to suppress ABA DTH. Gel filtration of ABA suppressor factor(s) showed that the majority of the suppressive activity was present in a fraction with molecular weight ranging between 6.8 x 10(4) and 3.3 x 10(4) daltons. We also analyzed for the presence of determinants encoded by the H-2 major histocompatibility complex (MHC) and found that immunoadsorbents prepared utilizing antisera capable of interacting with gene products of the whole or selected gene regions of H-2 MHC, i.e., B10.D2 anti-B10.A and B10 anti-B10.A immunoadsorbents, retained the suppressive activity of ABA-SF. Elution of such columns with glycine HCl buffers (pH 2.8) permitted recovery of specific suppressive activity. Taken collectively such data supports the notion that suppressor T-cell-derived ABA suppressor factors have antigen-binding specificity as well as determinants controlled by the K end of the H-2 MHC. The distribution of strains capable of making SF has also been analyzed. The relationship of the antigen-binding specificity to VH gene products is discussed in this and the companion paper.
Association of circulating retroviral gp70-anti-gp70 immune complexes with murine systemic lupus erythematosus.
Authors: Izui S , McConahey P J , Theofilopoulos A N , Dixon F J
Published: June 2004

Endogenous retroviral gp70 was investigated as a participant in the pathogenesis of a lupus-like disease that spontaneously develops in four kinds of mice (NZB, NZB x W MRL/1, and male BXSB). Sera from these strains contain a heavy form of gp 70 that varies in sedimentation rates from 9S to 19S in sucrose density gradient analysis and appears with the onset of disease and persists throughout its course. Immunologically normal strains of mice do not develop rapidly sedimenting gp70 by 8-10 mo of life. The fact that the heavy gp70 is selectively absorbed with anti-IgG antibodies or with Staphylococcus aureus protein A suggests that it is complexed with antibodies. The incidence and quantities of these gp70 ICs rise with the progression of disease in all strains with lupus. These findings suggest that Ig-complexed heavy gp70 may be involved in the pathogenesis of glomerulonephritis of mice with SLE.
Induction and mode of action of suppressor cells generated against human gamma globulin. II. Effects of colchicine.
Authors: Parks D E , Shaller D A , Weigle W O
Published: June 2004

The ability of colchicine (Col) to interfere with suppressor cells specific for the soluble protein antigen human gamma globulin (HGG) has been examined. This interference may be the mechanism of the adjuvanticity promoted by Col. When injected into A/J mice at the appropriate time and concentration, both Col and cyclophosphamide promoted an adjuvant increase in the plaque-forming cell response to 100 micrograms of immunogenic, aggregated HGG. Col abrogated both the induction of suppressor cells when injected with 3 h of tolerization with deaggregated (DHGG) and the expression of previously induced suppressor cells when injected with the antigenic challenge. Interference with the generation and expression of antigen-specific suppressor cells had no detectable effects on the immunologic unresponsive state to HGG. Col did not interfere with the induction of tolerance at a dose (1 mg/kg) that abolished the generation of suppressor cells. Furthermore, the absence of colchicine-sensitive-suppressor cells during the establishment of tolerance had no observable effect on the duration of unresponsivness in either helper T- or B-lymphocyte populations. Finally, Col was not able to terminate the unresponsive state established by DHGG even when responsive splenic B cells could be demonstrated in tolerant animals. These data indicate that suppressor cells are not required for the establishment and maintenance of the unresponsive state to this antigen.
Active suppression of 1-fluoro-2,4-dinitrobenzene-immune T cells. Requirement of an auxiliary T cell induced by antigen.
Authors: Sy M S , Miller S D , Moorhead J W , Claman H N
Published: June 2004

We investigated T-T cell interactions in the suppression of contact sensitivity. Suppressor cells that block the efferent limb of sensitivity (Ts-eff) can inhibit the passive transfer of contact sensitivity mediated by 1-fluoro-2,4-dinitrobenzene immune cells (T DH). But, Ts-eff cannot block the passive transfer of TDH which comes from cyclophosphamide (Cy) pretreated sensitized mice. We interpret these results to indicate that lymph node cells from sensitized mice contain not only TDH but also another intermediate cell which is required for the suppression of TDH by Ts-eff. This intermediate cell is sensitive to cyclophosphamide and requires antigen activation for its development. It is sensitive to adult thymectomy and anti-brain associated theta serum and is therefore designated as an auxiliary T-suppressor cell (Ts-aux). It is not sensitive to splenectomy and it carries I-J determinants. Ts-aux are required for the activity of suppressors of the efferent limb (Ts-eff) but not of suppressors of the afferent limb (Ts-aff). Thus, in the feedback loops in contact sensitivity, the generation of Tdh is coordinated with the development of auxiliary Ts which are essential for the suppression of those TDH.
H-2 I-region encoded targets in allograft rejection.
Authors: Gose J E , Bach F H
Published: June 2004

Fresh thyroids transplanted to I-region disparate recipients are, in most cases, rejected; in some instances fresh thyroids undergo periods of crisis followed by functional recovery. Cultured thyroids that are taken from donor animals pretreated with lymphocytotoxic drugs, gamma radiation and cultured for 10 d in vitro are not rejected by any normal allogenic recipient. If the recipient is sensitized with lymphoid cells syngeneic with an I-region disparate cultured thyroid donor, the cultured thyroid is rejected if I-A-subregion differences are included. We interpret these data to indicate that there exist I-region encoded perenchymal cell target determinants which are not, by themselves, immunogenic.
Determination of the kappa anti-alpha(1,3) dextran immune response difference by A gene(s) in the VKappa-locus of mice.
Authors: de Preval C , Blomberg B , Cohn M
Published: June 2004

Mice lacking the V(alpha(1,3) (h gamma1)-gene do not produce a gamma1 anti-alpha(1,3) dextran response. However, on hyperimmunization some strains mount a kappa-anti-alpha(1,3) dextran response, whereas other remain nonresponder. Responsiveness in dominant. The kappa-anti-alpha(1,3) response difference is linked to the Ly-3 locus on chromosone 6 and is likely the result of a structural Vkappa-gene(s). In conjunction with previous work, three Vkappa-allogroups can now be distinguished. At present, this is the only example of an immune responsiveness difference associated with the Vkappa-locus.
The in vitro effects of Bordetella pertussis lymphocytosis-promoting factor on murine lymphocytes. IV. Generation, characterization, and specificity of cytotoxic lymphocytes.
Authors: Kong A S , Morse S I
Published: June 2004

Cytotoxic effector lymphocytes were induced in cultures of mouse spleen or lymph node cells by lymphocytosis promoting factor (LPF). The LPF-activated cytotoxic cells: (a) were not generated unless proliferation occurred; (b) sedimented in the lighter density fraction of a bovine serum albumin gradient; (c) were large, blast-like cells; and (d) were lysed by Thy-1.2 antiserum plus complement and, therefore, were T cells. Neither LPF alone nor supernates from stimulated cultures were cytotoxic. Unlike the situation with concanavalin A and phytohemagglutinin P, LPF-stimulated cytotoxic effector lymphocytes required no further addition of mitogen for maximal cytotoxicity. The effector cells displayed specificity, destroying only allogeneic but not syngeneic normal cells; in the case of tumor cells, both allogeneic and syngeneic cells werelysed in the absence of added mitogen. The reason for differentiated cytotoxicity toward syngeneic tumor and normal cells is not clear but may have some relevance to in vivo tumor rejection initiated by Bordetella pertussis.
H-2-linked genetic control of murine T-cell-mediated lympholysis to autologous cells modified with low concentrations of trinitrobenzene sulfonate.
Authors: Shearer G M , Schmitt-Verhulst A M , Pettinelli C B , Miller M W , Gilheany P E
Published: June 2004

Spleen cells from B10.BR and C57BL/10 (B10) mice were compared for their ability to generate primary in vitro cytotoxic responses to syngeneic cells modified with different concentrations (from 10 to 0.031 mM) of trinitrobenzene sulfonate (TNBS) (TNP-self). Although both strains generated effector cells to TNP-self in the range of 10-0.25 mM TNBS modification, effector activity of B10 cells was weaker than that of B10.BR cells. B10 spleen cells did not respond to syngeneic stimulating cells modified at 0.1 mM or lower, whereas B10.BR cells generated effector activity even when stimulated by TNP-self modified with as low as 0.031 mM TNBS. Fluorescence analysis of the modified cells using the FACS II indicated that equivalent quantities of TNP were conjugated to the surfaces of B10.BR and B10 spleen cells for any given concentration of TNBS modification. Similar strain-dependent differences were observed when the TNP was diluted out in the cultures by reducing the number of stimulating cells modified with 10 mM TNBS. These response patterns were verified by stimulating cultures of B10.BR and B10 spleen cells either with TNP conjugated to bovine serum albumin or bovine gamma globulin (B10.BR but not B10 cells responded to TNP-conjugated proteins) or with TNBS-modified glass-adherent spleen cells. The strain-dependent differences could also be detected at the effector phase, because optimally stimulated B10.BR, but not B10 effector cells, could lyse 0.1 mM TNBS-modified syngeneic target cells. The genetic parameters associated with the response and nonresponse patterns of B10.BR and B10 mice were further investigated by comparing the cytotoxic responses to low doses of TNP-self of spleen cells from the following strains: (a) C3H/HeJ (H-2k) and C3H.SW (H-2b); (b) BALB.K (H-2k) and BALb.b (h-2b); and (c) B10.A (H-2a) and B10.D2 (H-2d). The H-2k and H-2a, but not the H-2b and H-2d, strains generated cytotoxic responses to TNP-self when the syngeneic stimulators were modified with 0.1 mM TNBS. Further studies using (B10 X B10.BR)F1 responding cells and parental or F1-modified stimulating cells, indicated that the F1 cells generated cytotoxic activity to low doses of TNP in association with H-2k but not in association with H-2b self products. The results of this study indicate that H-2-linked genetic factors, expressed in the target as well as in the responding and/or stimulating cell populations, control the ability of inbred mouse strains to generate cytotoxic effector cells to low doses of TNP-self. Such dose-dependent genetic effects may be important in the regulation of immune responses activated in vivo by chronic exposure to infectious agents.
Purification and properties of an extracellular blastogen produced by group A streptococci.
Authors: Gray E D
Published: June 2004

An extracellular product of group A streptococci which induces lymphocyte blastogenesis has been purified to homogeneity by DEAE-cellulose and CM-cellulose chromatography. The protein, termed streptococcal blastogen A, has a mol wt of approximately or equal to 17,500 and is inactivated by protease treatment and by heating at 100 degrees C. The purified blastogen gave rise to multiple protein bands on nondenaturing polyacrylamide gel electrophoresis, only two of which possessed blastogenic activity. Treatment of the protein with dithiothreitol before electrophoresis resulted in the apparent conversion of the multiple forms to a single active species. Blastogen A differs in electrophoretic mobility from the streptococcal pyrogenic exotoxins and its lymphocyte stimulating activity is not inhibited by rabbit antisera to the exotoxins. An enzyme immunoassay has been developed to measure human antibodies against blastogen A. A selection of sera with varying levels of anti-DNase B contained antiblastogen A-IgG.
Origin, Kinetics, and characteristics of pulmonary macrophages in the normal steady state.
Authors: van oud Alblas A B , van Furth R
Published: June 2004

Pulmonary macrophages of mice in the steady state were isolated by lavage with PBS containing EDTA and subsequent enzymatic digestion of tissue with pronase and DNA-ase. By this method, the total pulmonary macrophage population was obtained in two cell suspensions, one with a pure population of pulmonary alveolar macrophages (PAM) and the other with a mixed population of pulmonary alveolar and pulmonary tissue macrophages (PTM). The morphological, cytochemical, and functional characteristics of both PAM and PTM were like those of mature tissue macrophages except for the presence of C3 receptors. These receptors were almost absent on PAM and present on a larger number of cells in the mixed population of PAM and PTM. The total pulmonary macrophage population of mice in the steady state is approximately equal to 2 x 10(6), of which about 93% are PAM and about 7% are PTM. In labeling experiments with 3H-thymidine, the low in vitro labeling indices (less than 3%) for both PAM and the mixture of PAM and PTM, showed that both are essentially nondividing cells. In vivo labeling studies showed an increase in the number of labeled macrophages that can only be attributed to labeled monocytes migrating into the lungs. Additional evidence was provided by a decrease in the labeling indices of pulmonary macrophages when mice were treated with hydrocortisone acetate, which causes a severe monocytopenia, thus preventing monocyte influx into the lungs. Confirmation of the bone marrow origin was obtained in mice labeled after x-irradiation with partial bone marrow shielding: labeled pulmonary macrophages were found in the exposed lungs. In all experiments, the labeling indices were identical in the two macrophage populations isolated. These results show that the influx of monocytes is the source of cell renewal for the pulmonary macrophages. No indications for an interstitial division or maturation compartment in the lung were found. Quantitation of the efflux of labeled monocytes from the blood, and the number of labeled pulmonary macrophages, showed that in the steady state about 15% of the monocytes leaving the circulation become pulmonary macrophages and that the turnover time of pulmonary macrophages is approximately equal to 27 d.
Specificity and function of a human autologous reactive T cell.
Authors: Hausman P B , Stobo J D
Published: June 2004

Normal human peripheral blood contains a population of T cells (autologous reactive cells [ARC]) capable of proliferating in response to signals from autologous B cells and monocytes. Selective suicide of proliferating ARC with 5-bromo-2-deoxyuridine and light demonstrated that this ARC was responsive to signals coded for by genes more closely linked to the HLA-DR, than to the HLA-A, or HLA-B, loci. Density-gradient fractionation of T cells indicated that populations enriched in ARC reactivity were also enriched for helper influences required for Ig synthesis by autologous B cells. In contrast, populations negatively selected for proliferating ARC were deficient in helper activity. These studies indicate that the ARC is responsive, at least in part, to products of genes closely linked to the HLA-DR locus and can function as a helper cell.
The absence of H-2 antigens from mouse pancreatic beta-cells demonstrated by immunoferritin labeling.
Authors: Parr E L
Published: June 2004

Islets of Langerhans were isolated from mouse pancreases and fixed in periodatelysine-paraformaldehyde. The fixed islets were then dissociated with trypsin and EDTA to yield cell suspensions that contained mainly four cell types; beta-cells, capillary endothelial cells, acinar cells, and pancreatic duct epithelial cells. The nonislet cells were probably associated wtih the surface of the isolated islets. The H-2 antigens of the dissociated pancreatic cells were labeled with an immunoferritin technique. Pancreatic duct epithelial cells showed specific ferritin labeling on their lateral cell membranes but not on apical microvillus membranes. Acinar cells were also labeled on lateral membranes, and the capillary endothelial cells were labeled on both the luminal and albuminal aspects of their surface membranes. In contrast, pancreatic beta-cells were unlabeled. The number of ferritin molecules per unit length of beta-cell membrane was essentially the same on cells from the antigenic strain and the congeneic control strain, and was about 200-fold less than on the labeled pancreatic duct epithelial cell lateral membranes. Pancreatic beta-cells are therefore one of six known epithelial cell types on which H-2 antigens can not be detected by immunoferritin labeling. The apparent absence of H-2 antigens from these cells suggests a study of the viability of beta-cells in allografts of dissociated islet cells, in which the beta-cell would not be in contact with antigenic cells. Such studies might lead to a new approach to the control of diabetes mellitus by transplantation.
Antibody-dependent cell-mediated antibacterial activity of human mononuclear cells. I. K lymphocytes and monocytes are effective against meningococi in cooperation with human imune sera.
Authors: Lowell G H , Smith L F , Artenstein M S , Nash G S , MacDermott R P
Published: June 2004

In cooperation with human heat-inactivated antisera from adults immunized with group C meningococcal polysaccharide, normal human peripheral blood mononuclear cells significantly decreased the viability of group C meningococci (Mgc) in vitro. K lymphocytes (Null cells) and monocytes, (but not T or B lymphocytes) were capable of effecting antibody-dependent cell-mediated (ADC) antibacterial activity in this system. The degree to which meningococcal viability was decreased was a function of the length of the test incubation, the concentration of effector cells, and the amount of antiserum used in the assay. When specific antibodies directed against Mgc were adsorbed from the antiserum, cell-mediated antibacterial activity was abolished. ADC antibacterial activity was also abrogated by performing the assay at 4 degrees C or by heating effector cells to 46 degrees C for 15 min before the assay, Similarities between the ADC antibacterial system and previously described ADCC assays are discussed. The data suggest the K cells (as well as monocytes) may play a role in host immune defense against pathogenic bacteria.
Autoregulation of an antibody response via network-induced auto-anti-idiotype
Authors: Brown JC , Rodkey LS
Published: June 2004

The antibody response of a single outbred rabbit was studied throughout three rounds of injections with Micrococcus lysodeikticus vaccine over a 31-mo period. The first-round response was characterized by a vigorous anti- micrococcus response and a strong anti-IgG rheumatoid factor response. The second-round response consisted of a triad of interacting molecules: anti- micrococcal antibodies, autoanti-idiotypic antibodies specific for distinct clonotypes of the first-round anti-micrococcal antibodies, and Fc-specific anti-IgG rheumatoid factor. The interacting triple complex was detected because of the formation of an immune complex that became insoluble upon dilution of the serum. Complex formation was inhibited in the presence of saccharide compounds known to be major immunodominant determinants of the micrococcal cell-wall carbohydrate polymer. The same saccharides did not affect the reaction of rheumatoid factor with IgG. Direct-binding radioimmunoassays ruled out mediation of the dilution-precipitation reaction by soluble micrococcal antigens. Specific absorption of rheumatoid factor inhibited the dilution-precipitation reaction. Auto-anti-idiotypic antibodies were specifically purified from second-round sera, directly confirming the presence of these antibodies. Suppressive effects of auto-anti-idiotypic antibodies on distinct antibody clonotypes were shown by gel isoelectric focusing of first-, second-, and third-round sera. Clonotypes expressed in the first round of immunizations were reduced in quantity or absent when auto-anti-idiotypic antibodies were detectable. Greatly enhanced levels or initial synthesis of new clonotypes of anti-micrococcal antibodies were detected during the period of auto-anti-idiotype synthesis. The third-round sera, devoid of detectable auto-anti-idiotype, contained clonotypes characteristic of both first- and second-round antisera. Thus, auto-anti- idiotypic-mediated suppression appeared to be reversible. The data are interpreted as lending strong support for concepts of autoregulation of immune processes in normal outbred animals via an idiotypic network.
Secretion of plasminogen activator by bone marrow-derived mononuclear phagocytes and its enhancement by colony-stimulating factor
Authors: Lin H-S , Gordon S
Published: June 2004

We have studied the production of plasminogen activator (PA) by mononuclear phagocytes derived from mouse bone marrow precursor cells (CFU-C) in culture. Bone marrow-derived macrophages (BMDM) obtained after 6-8-d cultivation in a liquid medium containing L-cell-conditioned medium (LCM), a source of colony stimulating factor (CSF), showed a high level of fibrinolytic activity comparable to that of thioglycollate medium-induced peritoneal macrophages (TPM) and at least 20-fold higher than that of resident peritoneal macrophages (RPM). Fibrinolysis was a result of active secretion of PA into the culture medium and plaques of caseinolysis could be detected by an overlay assay over all macrophage colonies formed after cloning of bone marrow cells in culture.

When the fibrinolytic activity of BMDM harvested at different times was investigated, it was found that the level of PA activity of a given BMDM population correlated well with the incidence of cells (5-15 percent) able to proliferate and form colonies in agar after 7-14 d, somewhat more slowly than CFU-C. This correlation between the level of PA secretion and the incidence of agar colony-forming cells was also found with other mononuclear phagocyte populations. Active fibrinolysis and slow growing colony-forming cells were observed at the same time as adherent macrophages appeared, 2-3 d after the start of bone marrow culture, they persisted for 10 d before declining.

Some of the factors which influenced PA production by BMDM were examined. Fibrinolysis could be enhanced two- to fourfold by exposing the cells for 4 h to concanavalin A (Con A), to medium conditioned by Con A-stimulated spleen cells and to LCM, but not by phagocytosis of latex particles. The substance in LCM that stimulated PA production appeared to be identical to CSF. Mononuclear phagocyte targets differed in their response to LCM, which stimulated fibrinolysis readily in BMDM, to a lesser extent in TPM and not at all in RPM.

We conclude that CSF stimulates both proliferation and fibrinolytic activity in BMDM and that the level of macrophage activation, as defined by PA production, can be further enhanced by lymphokines. Induction of PA in BMDM provides a rapid and sensitive assay for measuring the activity of CSF and defining its role in macrophage activation.
Ia determinants on stimulated human T lymphocytes. Occurrence on mitogen- and antigen-activated T cells.
Authors: Ko H S , Fu S M , Winchester R J , Yu D T , Kunkel H G
Published: June 2004

Human T-cell blasts were generated by stimulation with mitogens and antigens. A proportion of these blasts expressed Ia antigens detectable by immunofluorescence with both allo- and hetero-antiserums. The maximal expression of Ia antigens was delayed and usually occurred after the peak of blastogenesis. Among the three mitogens used, pokeweed mitogen (PWM) was most effective in giving a high percentage and intense Ia staining of T-cell blasts. Phytohemagglutinin and concanavalin A blasts gave weaker and lower percentages of Ia staining. Activation by alloantigens and soluble antigens such as tetanus toxoid and purified protein derivative resulted in Ia expression on T cells comparable to PWM stimulation. Depletion of Ia+ cells from freshly isolated T cells with anti-Ia and complement decreased subsequent Ia expression, suggesting that a proportion of Ia+ blasts were derived from Ia-bearing peripheral blood T cells. When the specificities of the Ia antigens on T-cell blasts were examined with alloantiserums, it was evident that the T blasts expressed similar HLA-DR determinants to those on B cells from the same donor; occasional minor differences between stimulated T cells and autologous B-cell lines or fresh B cells were encountered.
Monocytes regulate osteoclast-activating factor production by releasing prostaglandins.
Authors: Yoneda T , Mundy G R
Published: June 2004

Osteoclast-activating factor (OAF), a powerful stimulator of osteoclastic bone resorption, is released by peripheral blood mononuclear cells on exposure to phytohemagglutinin (PHA) or a specific antigen to which the leukocytes have been previously exposed. Both lymphocytes and monocytes are required in the leukocyte population for OAF release to occur. In this study we examined the relationship between the lymphocyte and monocyte in OAF production. Biological activity, as a result of OAF, was assessed by a bioassay based on the release of previously incorporated 45Ca from fetal rodent long bones in organ culture. We found that an enriched lymphocyte population depleted of monocytes by serial adherence does not release OAF after stimulation with PHA, although the cells are activated as assessed by [3H]thymidine and 3H-amino acid incorporation. When conditioned media harvested from adherent cells which did not contain OAF was added to the enriched lymphocytes, OAF release occurred. Media harvested from adherent cells which were cultured with indomethacin (10 microM), an inhibitor of prostaglandin synthesis, did not permit OAF release by activated lymphocytes. When PGE1 and PGE2 (0.1 microM) were added exogenously to the enriched lymphocyte population, OAF release occurred after stimulation with PHA. These results indicate that, (a) the activated lymphocyte is the cell or origin of OAF, (b) prostaglandins produced by monocytes are necessary for OAF production by activated lymphocytes, and (c) monocyte prostaglandins can influence bone resorption indirectly by regulating OAF production as well as directly by osteoclast activation. The interactions of OAF and prostaglandins at bone resorbing sites may be important in inflammatory and neoplastic diseases associated with bone destruction.
The role of monocytes in serum sickness nephritis.
Authors: Hunsicker L G , Shearer T P , Plattner S B , Weisenburger D
Published: June 2004

We have investigated the pathogenesis of glomerular hypercellularity seen in acute serum sickness nephritis induced in rabbits with bovine serum albumin (BSA). The increase in cellularity began with the first stages of immune clearance of BSA, with a peak cellularity occuring at the time of onset of proteinuria. Although there was a significant increase in the fraction of glomerular cells incorporating [3H]thymidine, first seen at the onset of proteinuria, this increase occurred too late and was too small to explain the observed rate of increase in glomerular cellularity. On the other hand, a striking monocytic infiltration of the glomeruli was documented by electron microscopy and by staining for nonspecific esterase. This monocytic infiltration paralleled the observed course of glomerular hypercellularity and was quantitatively sufficient to explain the total increase seen. It appears, therefore, that glomerular hypercellularity seen in this model is principally a result of monocyte infiltration.
Tumor necrosis serum induces a serologically distinct population of NK cells.
Authors: Chun M , Pasanen V , Hämmerling U , Hämmerling G F , Hoffmann M K
Published: June 2004

Murine spleen cells generate nonspecific cytotoxic cells, referred to as natural killer (NK) cells, within 4 d of incubation in Mishell-Dutton cultures. This NK cell type does not arise in cultures of BALB/c.nu spleen cells or in cultures of T-cell depleted C57BL/6 spleen cells, indicating that its activation depends on T cells. Another type of NK cells is induced by tumor necrosis serum in murine spleen-cell cultures. It arises within 24 h and its activation does not depend on T cells. This cell type (and its precursor) expresses the recently discovered cell-surface marker Qa5 (controlled by the Q region of chromosome 17) that distinguishes this NK cell from the NK cell that depends for its activation on thymic function. Qa5+ NK cells are also induced by interferon.
Mouse alloantibodies capable of blocking cytotoxic T-cell function. I. Relationship between the antigen reactive with blocking antibodies and the Lyt-2 locus.
Authors: Shinohara N , Sachs D H
Published: June 2004

In an attempt to produce allonatibodies to cytotoxic T-cell receptors, hyperimmune anti-lymphocyte antisera have been raised in mice of various strain combinations, and have been tested for their ability to block allogeneic cell-mediated lymphocytotoxicity (CML) in the absence of complement at the T killer cell level. Most of the sera failed to show any significant and reproducible inhibitory effects. However, among C3H anti-B10.BR antisera, some sera were found to be capable of significantly inhibiting CML. This effect was attributable to antibodies reacting with the killer population rather than the target cells, because the sera inhibited B10 anti-C3H CML but not C3H anti-b10 CML. Among mouse strains tested, A/J, BALB/c, B10, and B6 strains were sensitive to the inhibitory effect of the sera whereas AKR, CBA, C3H, and DBA/2 strains were insensitive. The sensitivity of killer cells to the inhibitory effect correlated well with the strain distribution of the Lyt-2.2 antigen. In the presence of complement, these same sera were toxic to 100% of spleen cells of AKR, BALB/c, B10, and DBA/2 strains, with comparable cytotoxic titers. Thus, the inhibitory activity of the sera could not be explained by nonspecific effects of high-titered antibodies. To study the relationship between the antigen(s) responsible for the blocking effect and Lyt-2-linked genes, killer cells from Lyt-2 congenic strains were tested and conventional anti-Lyt-2.2 antisera were raised in an appropriate congenic strain combination. Killer cells from B6, but not from B6.Ly2.1 animals, were significantly sensitive to the blocking effects of the inhibitory C3H anti-B10.BR sera. The conventional anti-Lyt.2.2 sera did produce CML blocking, although there was no apparent correlation between such blocking and the anti-Lyt-2.2 cytotoxic titer. These results thus indicate that the target molecules responsible for blocking of killer cells are encoded or regulated by genes that are closely linked to or identical with Lyt-2.
The fate of fetal and adult B-cell progenitors grafted into immunodeficient CBA/N mice.
Authors: Paige C J , Kincade P W , Moore M A , Lee G
Published: June 2004

The relative ability of various precursors to generate functional B cells in vivo was assessed by transferring normal, chromosomally-marked CBA/H-T6T6 cells to irradiated or unirradiated immunodeficient CBA/N mice. Emergence of donor-derived B cells was monitored by means of a B-cell cloning assay (in which CBA/N cells are inactive), and by karyotpic analysis of lymphoid, myeloid, and stem cell metaphases. Grafts of lymph node, spleen, anti-mu surface immunoglobin suppressed bone marrow, sIg+ cell-depleted marrow, normal marrow, fetal liver, and yolk sac suggest: (a) there is little self-renewal of sIg+ B cells in these models; (b) pre-committed cells have extensive proliferative/differentiative potential and at least initially contribute most of the newly-formed B cells; (c) populations or pre-B cells obtained from various sources differ in their regenerative ability; (d) CBA/N mice are deficient in a category of pre-B cells which are found in fetal liver; and (e) selective B-cell chimerism results from grafting of unirradiated CBA/N mice.
Cell surface antigens of human renal cancer defined by autologous typing.
Authors: Ueda R , Shiku H , Pfreundschuh M , Takahashi T , Li L T , Whitmore W F , Oettgen H F , Old L J
Published: June 2004

Sera from 28 patients with renal cancer were tested for reactivity with surface antigens of cultured autologous renal cancer cells. Four serological assays were used to survey sera for autologous antibody. Immune adherence, protein A, and C3-mixed hemadsorption assays detected reactivity in a high percentage of patients (80-100%), whereas mixed hemadsorption assays were negative with sera from all but one patient. Reactive sera from six patients were analyzed by absorption tests with autologous, allogeneic, and restricted to autologous renal cancer cells; class 2 antigens, present on certain allogeneic renal and nonrenal cancer cells; and class 3 antigens, found on a wide variety of normal and malignant cell types. The sera of one patient detected class 1, 2, and 3 antigens, the sera of three patients detected class 2 antigens, and the sera of two patients detected class 3 antigens. This analysis of renal cancer, with the recognition of three classes of surface antigens recognized by autologous sera, resembles the results of autologous typing of three other human malignancies: malignant melanoma, acute leukemia, and astrocytoma. Evidence provided by autologous typing of these cancers indicates that class 1 and class 2 antigens are tumor-restricted and that under certain circumstances these antigens are immunogenic for the autologous host.
Characterization of a monoclonal antibody directed against mouse macrophage and lymphocyte Fc receptors.
Authors: Unkeless J C
Published: June 2004

To investigate the antigenic relationship between the macrophage and lymphocyte Fc receptors (FcR), a monoclonal antibody capable of blocking mouse macrophage Fc receptors was selected. Hybrids were formed by fusing the P3U1 mouse myeloma and spleen cells from a rat immunized with the mouse macrophage-like cell lines J774 and P388D1. The Fab fragment of the monoclonal IgG secreted by clone 2.4G2, inhibited the trypsin-resistant Fc receptor II (FcRII), which is specific for immune aggregates of mouse IgG1 and IgG2b, but had no inhibitory effect on the trypsin-sensitive Fc receptor I (FcRI), which binds monomeric IgG2a and erythrocytes coated with IgG2a. Thus, the monoclonal 2.4G2 IgG appeared to be specific for macrophage FcRII. Further evidence that the 2.4G2 IgG was directed against FcRII came from binding studies of the monoclonal antibody to J774 cells and a series of independently isolated variants which do not express FcRII. These variants of J774 bound 5% as much of the monoclonal antibody as the parent line, which bound 600,000 molecules of 2.4G2 IgG per cell. The antigenic relatedness of mouse lymphocyte FcR to mouse macrophage FcRII was demonstrated by the binding of 2.4G2 IgG to FcR-bearing lymphoid cell lines and the inhibition of the lymphocyte FcR by the monoclonal antibody. Preincubation of spleen cells and peritioneal cells with 2.3G2 IgG likewise inhibited rosette formation with ox erythrocytes coated with rabbit IgG. The ability of the hybridoma IgG to inhibit mouse FcRII was independent of the major histocompatibility complex. The 2.4G2 IgG antigenic determinant was not present on rat, guinea pig, rabbit, or human FcR-bearing cells.
Adherent cell function in murine T-lymphocyte antigen recognition. IV. Enhancement of murine T-cell antigen recognition by human leukocytic pyrogen.
Authors: Rosenwasser L J , Dinarello C A , Rosenthal A S
Published: June 2004

A macrophage-dependent, antigen-specific murine T-cell proliferation assay was utilized to examine the role of soluble products of murine and human adherent cells in the activation of T lymphocytes. Highly purified human leukocytic pyrogen, and supernates from both murine and human mononuclear phagocytes-macrophages stimulated the immune T-cell proliferative response to the multideterminant antigens dinitrophenyl-ovalbumin and keyhole limpet hemocyanin. The implications of these studies and the relationship of leukocytic pyrogen to human lymphocyte-activating factor are discussed.
T cells recognize minor histocompatibility antigens on H-2 allogeneic cells.
Authors: Forman J , Streilein J W
Published: June 2004

B10.A animals were rendered tolerant to B10.M spleen cells by injection of (B10.A X B10.M)F1 cells into neonates. Adult animals accepted B10.M skin grafts and failed to generate cytotoxic effector cells in vitro against B10.M H-2 antigens. In vivo inoculation of tolerant animals with A.CA spleen cells, followed by in vitro challenge with similar cells, resulted in the generation of cytotoxic effector cells that had specificity for the A strain minor histocompatibility (H)-antigens in the context of the H-2f haplotype. If these animals were boosted in vitro with A strain spleen cells, cross-priming could be demonstrated, whereby the cytotoxic effect was restricted by the H-2a haplotype. These data indicate that at least two sets of T cells co-exist in tolerant animals, one capable of recognizing antigens in the context of the host H-2 haplotype, and the other able to recognize antigens in the context of the tolerated H-2-allogeneic haplotype. Because tolerant animals inoculated with A-strain spleen cells in vivo and boosted in vitro with A.CA spleen cells failed to generate a cytotoxic effect against A.CA, it is unlikely that minor H-antigens need to be processed by host lymphoreticular cells.
Specific Lyt 123 cells are involved in protection against Listeria monocytogenes and in delayed-type hypersensitivity to listerial antigens.
Authors: Kaufmann S H , Simon M M , Hahn H
Published: June 2004

Specific anti-Lyt antisera and complement were used to determine the Lyt phenotype of peritoneal exudate T lymphocytes from Listeria monocytogenes-immune mice. It was found that Lyt 123+ T cells are crucially involved both in protection against listerial infection and in delayed-type hypersensitivity (DTH) to listerial antigens. Thus, both functions critically depend on a T-cell subclass phenotypically different from that which mediates DTH to noninfectious antigens and help in antibody formation on the one hand, as well as those T cells mediating cytotoxic reactions on the other.
Human immune response to immunization with a structurally defined polypeptide fragment of streptococcal M protein.
Authors: Beachey E H , Stollerman G H , Johnson R H , Ofek I , Bisno A L
Published: June 2004

We tested the ability of pepsin-extracted, highly purified M protein to induce type-specific immunity in experimental animals and humans. M protein was prepared from limited peptic digests of whole group A type 24 streptococci and was purified to chemical homogeneity as judged by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, quantitative amino acid analysis, and Edman degradation. For vaccination, the lyophilized M24 protein preparation (pep M24) was precipitated in aluminum hydroxide. When injected into laboratory animals, alum-precipitated pep M24 produced type-specific protective antibodies and was free of non-type-specific immunoreactivity. In man, skin tests with 1-microgram doses of pep M24 were negative in all 37 adults tested. 12 adult human volunteers received two-four subcutaneous injections of 100-200 micrograms of alum-precipitated pep M24 at intervals of at least 2 wk. The immune response to pep M24 was measured by a variety of assays designed to detect (a) type-specific humoral antibodies (opsonophagocytic, long chain, and mouse protection tests); (b) total humoral antibodies (complement fixation and enzyme-linked immunosorbent assay); (c) cellular immunity (skin tests); and (d) heart cross-reactive antibodies (immunofluorescence). Type-specific opsonic antibodies developed in 10 of the 12 vaccinees, and positive delayed-type skin tests developed in 11. Immune sera from two of the vaccinees were effective in mouse-protection tests against challenge with M24 but not M6 streptococci. None of the volunteers developed heart-reactive antibodies or antibodies to non-type-specific M protein antigens. Alum-precipitated pep M24 was well-tolerated in man, and no serious local or systemic reactions were observed. Thus, pep M24 induces type-specific, protective antibodies in doses that are well-tolerated in man.