bluuebunny/crossref_metadata_2025 huggingface dataset:
T cell recognition of the Sm nuclear antigen: induction of T cell proliferative responses in MRL/Mp- +/+ mice.
Authors: Cohen P L , Eisenberg R A
Published: December 2022

The role of T cell immunity against nuclear antigens recognized by autoantibodies in human and murine systemic lupus is unclear. We have studied the T cell proliferative response to purified Sm nuclear antigen by measuring in vitro 3H-thymidine incorporation by MRL/Mp- +/+ lymph node cells primed with Sm in Freund's adjuvant. Sm-primed cells responded in a dose-dependent fashion when cultured in vitro with purified Sm. Absorption of the Sm with solid-phase anti-Sm IgG from either of two lupus patients ablated the response, whereas control absorptions with normal IgG had no effect. Furthermore, cells from mice primed with physicochemically purified Sm responded in vitro to affinity-purified antigen, and vice versa. Treatment of cells with either anti-Thy-1 or anti-Lyt-1 and C eliminated Sm-induced proliferation, whereas anti-Lyt-2 treatment resulted in enhanced responses. MRL/Mp- +/+ mice, which made no detectable anti-Sm antibodies in vivo, were nonetheless capable of generating Sm-reactive T cells. These results indicate that T cells can specifically recognize the Sm nuclear antigen. Such recognition may be of importance in the generation of antibodies to Sm and other nuclear antigens in vivo.
Host immune response to reovirus: CTL recognize the major neutralization domain of the viral hemagglutinin.
Authors: Finberg R , Spriggs D R , Fields B N
Published: December 2022

Previous studies have demonstrated the importance of the hemagglutinin (HA) of reovirus in determining virus-specific immune responses. In this study, we have used anti-HA monoclonal antibodies and reoviruses with antigenically altered HA proteins to further analyze the CTL response against the HA. We showed that reovirus-specific CTL primarily recognize one distinct antigenic domain on the HA. These results emphasize the fine specificity of the T cell receptor that recognizes viral determinants. The CTL response is directed against the region of the HA that is also responsible for neurotropism and binding to neutralizing antibody.
Monoclonal antibody defining a Burkitt's lymphoma-associated antigen detects carbohydrate on neutral glycolipid.
Authors: Lipinski M , Nudelman E D , Wiels J , Parsons M
Published: December 2022

Monoclonal antibody 38.13 detects an epitope presented on Burkitt's lymphoma cells that has not been detected on other lymphoid tissues or tumors. The biochemical nature of this Burkitt's lymphoma-associated antigen was investigated by staining inhibition assays. Indirect immunofluorescence and fluorescence-activated cell sorter analysis show that antibody 38.13 reacts with a protease-resistant structure present among the hydrophobic components extracted with chloroform-methanol from the Ramos Burkitt's cell line. These components were further separated by ion-exchange chromatography and activity resides in the unbound (neutral) fraction. The staining antibody is specifically absorbed when preincubated with D-galactose, and to a lesser extent with N-acetyl-galactosamine. Therefore, 38.13 appears to recognize a determinant of carbohydrate nature, which is carried on a neutral glycolipid.
What Conclusions can be Drawn from the Different Degrees of the Dick Skin Test Reactions?
Authors: Johan Bela
Published: December 2022

We began in Hungary the confirmation of the Dick's work on skin tests and immunization against scarlet fever in the Summer of 1925. By January, 1926, we had Dick-tested about 17,000 individuals, and immunized those who gave positive reactions. This work is still in progress.

In the course of our work we came to the conclusion that the different degrees of the reactions have both theoretical and practical importance and must be taken into consideration.

We used a toxin prepared according to the Dick's original method with the Dick II strain of scarlet fever streptococcus. Our toxin was standardized on scarlet fever patients at the beginning of their illness and during convalescence, in Professor Bókay's clinic. Thirty-four children were tested on the first to the fifth day of their illness and 77 per cent were found to be positive with 0.1 cc. of toxin dilution of 1:1000.
Relation of Anaphylaxis to Immunity
Authors: Manwaring W. H. , Shumaker P. W. , Wright P. W. , Reeves D. L. , Moy H. B.
Published: December 2022

Summary and Conclusions

The blood of an actively immunized dog, therefore, contains no antibody that serves as a demonstrable circulating defense to hypersensitize fixed tissues.

The immune blood, however, does contain a desensitizing substance, capable of causing complete desensitization of hypersensitive fixed tissues.

This desensitization is effected only after a latent period of about forty-eight hours.

All phenomena of passive desensitization or passive immunization thus far studied in dogs may be accounted for as a result of the action of this desensitizing antibody.

As pointed out in previous papers (2, 4), there is conclusive evidence that in dogs the sensitizing antibody and desensitizing antibody are of different chemical composition, and that neither of these substances is identical with the specific precipitin of our test tube reactions.
On the Specificity of the Alcohol Soluble Substances of Acid-Fast Bacteria
Authors: Furth J. , Aronson J. D.
Published: December 2022

The alcohol soluble substances of acid-fast bacteria have been found to possess the following properties: (a) They fix antibodies produced with tubercle bacilli (Citron and Klinkert (1)); (b) they incite weak antibody formation when injected into normal animals (K. Meyer (2)). Immune sera produced with “lipoids” of the tubercle bacilli do not react with the extracted bacilli (K. Meyer (2, 3)), or with the protein fractions obtained from tubercle bacilli (Dienes and Schoenheit (7)). Thiele and Embleton (4) obtained strong group reactions with immune sera prepared with various fractions of the tubercle bacilli but the homologous fraction reacted better than the heterologous fractions. (c) The “lipoids” of mycobacteria differ from “lipoids” obtained from other organisms and from “lipoids” obtained from animal tissues (K. Meyer (2), Negre and Boquet (5, 6), Dienes (8) and others). However, by these studies very little specificity was demonstrated among the “lipoids” obtained from various mycobacteria.
Relation of Anaphylaxis to Immunity
Authors: Manwaring W. H. , Marino D. H. , McCleave T. C. , Boone T. H.
Published: December 2022

Summary and Conclusions

Titrations by means of rabbit precipitin indicate that horse proteins injected intravenously into normal dogs are retained apparently quantitatively in the circulating blood for at least four days. Nevertheless, transfusions of these bloods into partially exsanguinated hypersensitive recipients show that by the end of four days the circulating horse proteins are so altered that they are no longer capable of calling forth recognizable anaphylactic reactions in horse serum hypersensitive tissues.

In horse serum hypersensitive donors a similar complete anaphylactic detoxication of horse proteins without demonstrable quantitative reduction takes place in from ten to eighteen hours.

These findings are in harmony with our previous conclusion that marked chemical alterations take place in specific antigens when injected into the animal body and that many of the essential immunologic adaptations are to the resulting denaturization products (secondary antigens) rather than to the primary antigens originally injected.

If this conception of immunological adaptation is correct, it would indicate that there are numerous immunological processes and presumably numerous specific antibodies that can not be demonstrated by current serological methods.
The Smooth Muscle Reaction in the Serum Treated Earthworm
Authors: Ramsdell Susan Griffith
Published: December 2022

The rôle of the smooth muscle in anaphylaxis has been thus summarized by Kolmer (1).

The single prominent feature of anaphylaxis in all the species of animals is the effect upon the unstriated muscle. The lesions and symptoms in animals of different species are readily explained upon differences in the distribution of involuntary muscle. The exciting substance … produces immediate and transitory or protracted effects due to contraction which may be followed by relaxation. Such structural changes in the cells of various organs as have been described are readily explainable on the basis of vascular occlusion or dilitation with transudation.

In order to test the universality of the smooth muscle reaction as a manifestation of sensitization, the body-wall and the crop of the earthworm as smooth muscle preparations, as described by Straub (2) and Mines (3), were employed in this study.
Reciprocal Action of the Crop Muscles in Anaphylactic Shock, with a Note on the Effects of Heparin
Authors: Hanzlik P. J. , Butt E. M. , Stockton A. B.
Published: December 2022

The results with the intact pigeon crop described in a previous paper by Hanzlik and Stockton (1) dealt exclusively with the circular muscle. In this paper we wish to discuss the reciprocal action of the longitudinal and circular muscles described in a preliminary report (2). The results, it is believed, will prove interesting because (a) they demonstrate hitherto unsuspected muscular changes in the same organ during anaphylactic shock, (b) they are shown in an organ previously unused in, but well adapted to, the study of smooth muscle changes, and (c) the method of studying functional changes in the two muscular coats together is exceedingly simple.

Responses with Pressure in the Crop. In addition to the usual arrangement for recording changes in the circular muscle, i.e., with a distended balloon in the crop, described by Hanzlik and Stockton (1), a small figure “8” clamp is fastened to the crop in the vicinity of the distended portion.
Acquisition of suppressive activity and natural killer-like cytotoxicity by human alloproliferative "helper" T cell clones.
Authors: Pawelec G , Schneider E M , Wernet P
Published: December 2022

To investigate potential functional changes in alloantigen-specific proliferative CD3+, CD4+, CD8-, Leu-8-, interleukin 2 (IL 2)-secreting noncytotoxic in vitro primed human helper T cells, a set of 12 clones was studied sequentially throughout their finite life spans. Clones surviving to greater than 30 population doublings (PD) retained their requirements for exogenous IL 2 and filler cells for continued growth, but lost the ability to proliferate and to secrete IL 2 when specifically restimulated. This was not accompanied by changed surface marker phenotypes or acquisition of abnormal karyotypes, but was accompanied by the acquisition of MHC-unrestricted potent radioresistant suppressive activity for lympho-proliferative responses. Suppression was not caused by absorption of IL 2, secretion of interferons, de novo mycoplasma contamination, or cytotoxic activity. At least two suppressive mechanisms were demonstrated: 1) the induction of suppressor effectors in naive lymphocyte populations, which required cell to cell contact and could be inhibited by certain monoclonal antibodies against MHC class II determinants; and 2) a direct effect on responding lymphocytes, shown by suppressive activity on cloned PLT-active reagents. Moreover, the majority (75%) of originally allo-proliferative clones also acquired a previously absent cytotoxicity against natural killer (NK) cell-susceptible, but not NK-resistant, target cell lines. This modulation of function from specific alloproliferative, IL 2-secreting nonsuppressive status to strong nonspecific suppressive and NK-like cytotoxic status represents a novel functional activity of human T helper lymphocytes under conditions of clonal propagation.
Analysis of hemopoietic lineage of accessory cells in the developing thymus of Xenopus laevis.
Authors: Turpen J B , Smith P B
Published: December 2022

The developmental history of accessory cells in the thymus was studied by grafting hemopoietic stem cells into cytogenetically distinct frog embryos (diploid-2N or triploid-3N) before the establishment of circulation and overt differentiation and colonization of the thymus. The DNA content of cortical thymocytes and circulating erythrocytes was quantified by staining with propidium iodide and measuring the amount of red fluorescence emitted by individual nuclei with the use of flow cytometry. Accessory cells from thymic medulla were separated by incubating for 2 hr on glass slides. For comparison, the developmental history of peritoneal macrophages was examined as representative, myeloid-derived phagocytic cells. DNA content of adherent cells was quantified by staining with the DNA-specific Feulgen reaction and measuring light absorption of individual nuclei by microdensitometry. Thymic accessory cells were subdivided into phagocytic and nonphagocytic phenotypes on the basis of latex bead ingestion. Phagocytic cells in the thymus were usually nonspecific esterase positive and phenotypically resembled peritoneal macrophages. Nonphagocytic cells from the thymus were usually esterase negative and had a dendritic morphology characterized by branched cytoplasmic extensions. Nonphagocytic cells were positive for cytoplasmic RNA based on staining with methyl green-pyronin Y. Phagocytic cells from both the thymus and the peritoneal cavity had no levels of cytoplasmic RNA detectable by this method. Analysis of the embryonic derivation of thymic accessory cells, based on the proportion of cells carrying the cytogenetic marker, demonstrated that thymic lymphocytes and thymic accessory cells were a concordant pair of cells, distinct from myeloid-derived erythrocytes and possibly macrophages. These experiments provide circumstantial evidence suggesting thymocytes and thymic accessory cells could arise from a bipotential precursor that diverges into these separate lineages after colonization of the epithelial thymic rudiment during early development.
Antigen presentation by human dermal fibroblasts: activation of resting T lymphocytes.
Authors: Umetsu D T , Katzen D , Jabara H H , Geha R S
Published: December 2022

We have shown that human dermal fibroblasts, exposed to interferon-gamma (IFN-gamma) to induce surface class II major histocompatibility complex (MHC) antigens, were capable of presenting tetanus toxoid (TT) antigen to human TT-specific T cell clones. Antigen presentation by fibroblasts was antigen dependent, required HLA-DR expression by fibroblasts, and was MHC restricted. In contrast, we now report that IFN-gamma-treated fibroblasts are unable to present TT antigen to purified resting T cells obtained from the peripheral blood of TT-immune donors. In addition, although IFN-gamma-treated fibroblasts were able to stimulate alloreactive T cell clones, they were unable by themselves to stimulate primary allogeneic responses in resting T cells. The failure of fibroblasts to stimulate resting T cells was not due to suppressor effects by fibroblasts, because induction of TT and alloantigen responses in resting T cells by monocytes was not inhibited by the presence of fibroblasts. On the contrary, IFN-treated fibroblasts were synergistic with small numbers of monocytes in activating resting T cells. In addition, the failure of antigen presentation by fibroblasts to resting T cells was reversed by the addition of recombinant human interleukin 2 (rIL 2) to cultures, but not of purified human interleukin 1 (IL 1). These results emphasize that the requirements for activation of resting T cells differ from those of T cell clones. Although fibroblasts can efficiently present antigen to T cell clones, antigen presentation by fibroblasts to resting T cells requires the addition of exogenous IL 2. It is postulated that fibroblasts differ from classical antigen-presenting cells in that fibroblasts are incapable of stimulating the production of IL 2 in resting T cells.
Life span of B lymphocytes: the experimental basis for conflicting results.
Authors: Freitas A A , Rocha B , Coutinho A A
Published: December 2022

Recent claims have challenged the view that most peripheral, mature B cells are long-lived, and propose rates of peripheral decay that are compatible with bone marrow production. This disagreement can only reflect differences in the protocols and methods used to measure peripheral lymphocyte life spans. We have now assessed toxic or other nonselective effects of hydroxyurea treatment on the survival and migration of peripheral, noncycling cells, as well as possible reasons for exaggerated decays of LPS-reactive B cells transferred to LPS nonresponder hosts, the two methods leading to conclusions of short life spans. We also studied general effects on cell survival introduced by either repeated [3H]thymidine injections or the stress associated with surgery, thoracic duct cannulation in particular--methods with which the notion of long life spans had been established. The results failed to show toxic or nonselective effects of hydroxyurea treatments and artificial decays of LPS-reactive cells in adoptive hosts. In contrast, the present experiments demonstrate that both the stress associated with surgery and repeated [3H] thymidine administration profoundly deplete a pool of short-lived B cells, consequently selecting for an apparent higher proportion of long-lived cells.
Expression of a cross-reactive idiotype on rheumatoid factor in patients with Sjogren's syndrome.
Authors: Fox R I , Chen P , Carson D A , Fong S
Published: December 2022

Primary Sjogren's syndrome (SS) is a systemic autoimmune disorder characterized by lymphocytic infiltration of salivary and lacrimal glands. These patients have evidence of marked B cell hyperactivity, including the production of autoantibodies such as rheumatoid factor (RF) and an increased frequency of non-Hodgkin's lymphoma. We now demonstrate that RF from 12/15 SS patients contains a cross-reactive idiotype (CRI) on their kappa light chain defined by a monoclonal antibody (MoAb 17-109) and immunoblotting. This CRI was associated with immunoglobulin (Ig) A-RF, and to a lesser extent with IgM-RF molecules on the basis of direct binding studies. With the use of immunoperoxidase techniques to stain frozen tissue sections, B cells containing cytoplasmic Ig reactive with MoAb 17-109 were detected in the salivary gland biopsies from 11/12 SS patients at high frequencies, and in the blood from the same patients at much lower frequencies. One patient with pre-existant SS developed non-Hodgkin's lymphoma with tumor cells and RF paraprotein reactive with MoAb 17-109. Evaluation of serial biopsies over a 4-yr period showed a progressive increase in the proportion of B cells bearing the CRI. In contrast, synovial membrane biopsies from RA patients lacking sicca symptoms did not contain B cells expressing the CRI. Because previous studies have demonstrated that MoAb 17-109 detects a CRI on RF paraproteins from patients with lymphoma, B cells bearing this CRI may have increased frequency of neoplastic transformation. SS patients provide an opportunity to study the expression of this CRI and to understand the transition of B cell clones from autoimmune proliferation to neoplastic transformation.
Cell surface expression of invariant gamma-chain of class II histocompatibility antigens in human skin.
Authors: Claesson-Welsh L , Scheynius A , Tjernlund U , Peterson P A
Published: December 2022

A rat monoclonal antibody (McAb 21:9) reactive with the human invariant gamma-chain of class II major histocompatibility complex (MHC)-encoded antigens was isolated and was shown to react with the carbohydrate-carrying, COOH-terminal part of the gamma-chain. The McAb 21:9 binds to a molecule that is identified as the gamma-chain for the following reasons: it has an apparent m.w. of 33,000, similar to that of the gamma-chain; it has a two-dimensional gel migration pattern identical to that of the gamma-chain; and it associates with immature, but not processed class II antigens. When used for immunohistochemical staining on sections of normal human skin, only dendritic, class II MHC antigen, and anti-Leu-6 reactive Langerhans cells are labeled in the epidermis. HLA-DR-expressing keratinocytes present in the tuberculin reaction, cutaneous T cell lymphoma, and lichen planus, however, did not react with the anti-gamma-chain antibody, nor with a HLA-DQ-reactive antibody. Cell surface expression of the gamma-chain was observed on 1 to 3% of normal viable epidermal cells in suspension. By using double indirect immunofluorescence, it was possible to demonstrate the simultaneous binding of anti-gamma-chain, anti-HLA-DR, anti-Leu-10, and anti-Leu-6 antibodies, respectively, on the same cells, thus confirming their identity as Langerhans cells. The presence of the gamma-chain on the surface of the immunocompetent Langerhans cells may indicate that the cell surface, not the cytoplasm as has been suggested, is the site of the primary function of the gamma-chain.
Leu-1+ (CD5+) B cells. A major lymphoid subpopulation in human fetal spleen: phenotypic and functional studies.
Authors: Antin J H , Emerson S G , Martin P , Gadol N , Ault K A
Published: December 2022

Examination of the cell surface phenotype of fetal splenic lymphocytes demonstrated a major, novel subpopulation of B cells that co-express Leu-1 (CD5) in addition to B cell differentiation antigens (Leu-1+ B cells). These cells are similar to some conventional B cells in that they express HLA-DR, Leu-12, and B1, as well as both immunoglobulin (Ig) M and IgD. They comprise 40 to 60% of total splenic B cells in the fetus but are infrequent in fetal liver and adult spleen. Fetal Leu-1+ B cells do not respond to pokeweed mitogen with either proliferation or Ig secretion, and in contrast to the murine counterpart, Ly-1 B cells, they do not constitutively produce Ig. Leu-1+ B cells were incapable of augmenting Ig production of Leu-1- B cells when suboptimal numbers of T cells were present; however, they did require the presence of T cells to secrete antibody. They do not cap either the CD5 protein or surface Ig. These cells are a unique subpopulation of fetal splenic B cells that do not function as conventional B cells. Their role in the humoral immune response is unknown. They may represent the normal stage of B cell development, which is reflected in the phenotype of B cell CLL cells.
Increased T gamma and T mu cells in BALB/c mice with IgG and IgM plasmacytomas and hybridomas.
Authors: Mathur A , Lynch R G
Published: December 2022

The results of previous studies in our laboratory have shown that mice bearing plasmacytomas and hybridomas that secrete IgA or IgE are accompanied by increased frequencies of Lyt-1-2+ T lymphocytes bearing Fc receptors (FcR) for IgA (T alpha) or IgE (T epsilon), respectively. The present study was undertaken to examine whether IgG- or IgM-secreting tumors influenced the frequency of T lymphocytes that express FcR for IgG or IgM. We studied mice bearing IgG- and IgM-secreting plasmacytomas and hybridomas. BALB/c mice injected subcutaneously with the IgG-secreting hybridoma HDP1 (gamma 1 kappa, anti-TNP) were sequentially examined for the frequencies and Lyt phenotypes of splenic lymphocytes bearing FcR for IgG (T gamma), IgM (T mu), and IgA (T alpha). A threefold increase in the frequency of T gamma lymphocytes that were Lyt-1-2+, L3T4- was seen. The frequencies of T mu and T alpha lymphocytes in these mice were not significantly altered. Similarly, mice injected subcutaneously with the IgM-secreting plasmacytoma MOPC 104E (mu lambda, anti-dextran) or the IgM-secreting hybridoma C1D1 (mu kappa, anti-ox RBC) were examined sequentially for the frequencies of T gamma, T mu, and T alpha lymphocytes. Mice with established IgM subcutaneous tumors showed a twofold increase in splenic, nylon wool-nonadherent T mu lymphocytes. This was associated with a relative increase in Lyt-2+ splenic T lymphocytes and a relative decrease in Lyt-1+ splenic T lymphocytes. No changes were observed in the frequencies of either T gamma or T alpha lymphocytes. These studies extend to IgG and IgM the observation that plasmacytomas and hybridomas secreting immunoglobulins of a specific isotype cause an expansion of T lymphocytes bearing FcR specific for the corresponding isotype. The expansion of FcR+ Lyt-1-2+ T lymphocytes likely represents an exaggerated, but otherwise normal, immunoregulatory response of the host. These cells may be an important element in the regulation of isotype expression.
Human T4+ lymphocytes produce a phagocytosis-inducing factor (PIF) distinct from interferon-alpha and interferon-gamma.
Authors: Margolick J B , Ambrus J L , Volkman D J , Fauci A S
Published: December 2022

Unstimulated peripheral blood mononuclear cells from patients with angiocentric T cell immunoproliferative disorders and concanavalin A-stimulated normal peripheral blood mononuclear cells secrete a phagocytosis-inducing factor (PIF) that induces a fivefold to 50-fold enhancement of phagocytosis of IgG-coated ox red blood cells by U937 cells. We investigated the identity, production, and mechanism of the action of PIF. PIF activity was demonstrated in supernatants from nine of 44 phytohemagglutinin-stimulated interleukin 2 (IL 2)-dependent T cell lines and clones derived from purified T4+ cells, but was not found in supernatants from 26 lines and clones derived from phytohemagglutinin-stimulated T8+ cells. In addition, PIF was produced by four of four antigen-specific T cell lines and clones after stimulation with the appropriate antigen and antigen-presenting cells, and by HUT-102, a human T cell lymphotropic virus type I-transformed T cell line. PIF from all of these sources caused significant inhibition of U937 proliferation. This proliferation-inhibiting activity co-purified with phagocytosis-enhancing activity in sizing procedures and isoelectric focusing, which yielded an estimated m.w. of 35,000 to 55,000 and an estimated isoelectric point of 5.0 to 6.0 for PIF. In contrast, IL 2, recombinant interferon-alpha, and recombinant interferon-gamma had no effect on phagocytosis by U937 cells, and antibodies to interferon-alpha and interferon-gamma did not block the phagocytosis-inducing activity of PIF-containing supernatants. PIF appears to be a distinct lymphokine produced by a subset of T4+ lymphocytes, possibly those that proliferate in response to antigen. PIF may be important in the induction of erythrophagocytosis, which is associated with certain T cell immunoproliferative disorders.
Relationships between epitopes on IgE recognized by defined monoclonal antibodies and by the FC epsilon receptor on basophils.
Authors: Baniyash M , Eshhar Z , Rivnay B
Published: December 2022

The present study investigated whether the sites on the FC region of the IgE molecule, recognized by different anti-IgE monoclonal antibodies (mAb), are identical to those recognized by the Fc receptor (Fc epsilon R). The anti-IgE mAb recognize different clusters of epitopes on the Fc region of IgE and could interfere to different degrees with the binding of IgE to mast cells and basophils, but still recognized cell-bound IgE. Analysis of the stoichiometry and affinity binding of 125I anti-IgE mAb Fab' to free IgE have revealed that anti-IgE mAb of one group (51.3) recognized three repetitive determinants on the IgE Fc portion, and another group (95.3) recognized only one determinant. When these stoichiometric studies were performed with cell-bound IgE, it was found that only one of the sites recognized by 51.3 mAb was involved in the Fc epsilon R binding site. On the other hand, the site recognized by 95.3 mAb was not the Fc epsilon R binding site. Such findings establish mAb 51.3 as a useful tool for isolating the IgE peptides involved in the binding site to the receptor.
Biochemical characterization of the murine activated lymphocyte alloantigen Ly-6E.1 controlled by the Ly-6 locus.
Authors: Palfree R G , Hämmerling U
Published: December 2022

The Ly-6.1 alloantigen defined by monoclonal antibody SK70.94 and expressed predominantly on activated lymphocytes has been immunoprecipitated from lysates of cells biosynthetically radiolabeled with 35S-methionine. On SDS-polyacrylamide gel electrophoresis the reduced antigen appeared as a doublet of 17 and 18 kD. The nonreduced polypeptides had higher mobilities indicating intrachain but not interchain disulfide linkages. The nonreduced form was detectable by immunoperoxidase stain on blots after SDS-PAGE. This showed both polypeptide species contained the antigenic epitope. Labeling in the presence of tunicamycin did not change the apparent m.w. suggesting the absence of N-linked carbohydrate. Pulse-chase data are inconsistent with a strict precursor-product relationship between the two polypeptides and give a half-life for the antigen in 2-day Con A blast cells of about 4 1/2 hr. A highly purified preparation of this antigen displayed a similar electrophoretic pattern and, in the presence of deoxycholate, eluted from a Sephacryl S-200 gel filtration column with a partition coefficient equivalent to that of a 31-kD soluble globular protein. Because of the associated detergent and probable deviation from globularity, this is an over-estimate of the size of the native molecule, and is more consistent with the native molecule being a single polypeptide chain rather than a dimer. Isoelectric focusing of this material showed microheterogeneity with at least five bands between pI 4 and 5. Another monoclonal antibody, HD-42, which had been isolated on the basis of its specificity for a fibrosarcoma antigen subsequently found to be Ly-6 related, precipitated the same polypeptides. Furthermore, no obvious difference was evident between precipitates from Con A-activated lymphocytes and Meth A fibrosarcoma cells.
Murine cutaneous leishmaniasis: resistance correlates with the capacity to generate interferon-gamma in response to Leishmania antigens in vitro.
Authors: Sadick M D , Locksley R M , Tubbs C , Raff H V
Published: December 2022

The kinetics of cell-mediated immunity developed during the course of Leishmania major infection in resistant (C57BL/6) and susceptible (BALB/c) mice were determined by using in vitro bioassays. Cells isolated from the lymph nodes draining the infected footpads were assayed for their proliferative responses to leishmania antigens (promastigote and amastigote) or to concanavalin A (Con A). Although lymph node cells (LNC) from both mouse strains proliferated to mitogen and antigen early after infection, both C57BL/6 and BALB/c mice developed diminished in vitro proliferative reactivity within 3 to 5 wk after infection. LNC from both mouse strains recovered lymphoproliferative reactivity to Con A (week 6), but only C57BL/6 mice regained reactivity to leishmania antigens. BALB/c cells remained unresponsive to leishmania antigens throughout the subsequent course of the infection. Supernatants derived from cultures of LNC that had been stimulated with Con A or leishmania antigens were assayed for interferon-gamma (IFN-gamma) by analyzing three distinct activities associated with IFN-gamma. Culture supernatants derived from leishmania antigen stimulation of LNC from infected C57BL/6 mice, but not BALB/c mice, were able to induce surface Ia on murine P388D1 cells. Ia-inducing activity was detectable in supernatants from C57BL/6 cells as early as 3 wk, and peaked by 5 wk after infection. Although cells from infected BALB/c mice never produced detectable IFN-gamma in response to leishmania antigens, LNC from both mouse strains produced readily detectable IFN-gamma in response to Con A throughout the course of infection. Culture supernatants that induced Ia on P388D1 cells were also capable of activating resident peritoneal macrophages to display leishmanicidal activity and of inhibiting encephalomyocarditis virus replication in murine fibroblasts. Each of these activities could be removed by prior incubation of the supernatants with rabbit heterologous anti-murine IFN-gamma sera or monoclonal rat-anti-murine IFN-gamma. The correlation of healer status with the capacity to generate IFN-gamma in vitro in response to leishmania antigens was examined in BALB/c mice that had been exposed to sublethal irradiation (550 rad) before infection. These animals have been previously shown to effectively resist L. major infection. Consistent with observations in the genetically resistant C57BL/6 mice, LNC from these animals demonstrated the capacity to respond to in vitro leishmania antigen stimulation with lymphoproliferation, and more importantly, by producing IFN-gamma.(ABSTRACT TRUNCATED AT 400 WORDS)
Role of inflammatory cells in Chagas' disease. III. Kinetics of human eosinophil activation upon interaction with parasites (Trypanosoma cruzi).
Authors: Kierszenbaum F , Villalta F , Tai P C
Published: December 2022

The kinetics of human eosinophil activation and granule secretion initiated by interaction with Trypanosoma cruzi amastigotes was studied by using a monoclonal IgG1 antibody (termed EG2) that is specific for an epitope present only in the secreted forms of both eosinophil cationic protein (ECP) and the eosinophil protein X (EP-X), and hence not detectable in unstimulated resting eosinophils. Studies were carried out by using electron microscopy and indirect immunofluorescence. In the electron microscopy studies, deposits of protein A-gold particles in parasite-containing eosinophils that had been incubated previously with EG2 antibody were first detected 4 hr after initiation of the eosinophil-amastigote interaction. Control tests performed with a monoclonal IgG1 unreactive with eosinophils showed no deposition of protein A-gold particles. EG2 antibody binding was confined to the crystalloid granule matrix, where ECP and EP-X are known to be stored. A similar kinetic pattern of ECP/EP-X solubilization and secretion was confirmed by the results of the indirect immunofluorescence experiments also showing the binding of EG2 antibody after 4 hr of cell-parasite interaction. The kinetics of ECP/EP-X solubilization and secretion paralleled the kinetics of destruction of internalized amastigotes, suggesting a role for these basic proteins in parasite killing. Consistent with this notion was the detection of ECP/EP-X in the fluid of phagocytic vacuoles containing amastigotes and associated with the ingested organisms at the same time as the parasites began to show structural alterations. These results outlined the kinetics of eosinophil activation in terms of the time required for mobilization of two basic proteins associated with eosinophil secretion that are known to be biologically active.
The affinity threshold for antigenic triggering differs for tolerance susceptible immature precursors vs mature primary B cells.
Authors: Riley R L , Klinman N R
Published: December 2022

The specificity of antibody responses is dependent on the extent to which a given antigen selectively stimulates cells from within a diverse B cell repertoire. Previous studies have shown that the triggering of B cells by T cell-dependent antigens is a highly discriminatory process, and that tolerance induction of immature B cells by antigen is equally discriminatory. This symmetry in the requirements for stimulation and tolerance induction could provide a basis for the capacity of antibody responses to discriminate among foreign antigens and yet minimize self recognition. The extent to which this potential for discriminate recognition is applicable to the mature immune system remains controversial, because B cells reactive to self antigens have been identified and, in addition, several investigators have identified heteroclitic immune responses, such as the response to NP of Ighb mice, wherein antibodies are found with higher affinities for analogues of the immunogen than for the immunogen itself. To further investigate the capacity of B cells to discriminate among closely related antigenic determinants, we analyzed the fine specificity and idiotypic distribution of monoclonal antibodies derived from both splenic B cells and immature sIg- bone marrow B cell precursors stimulated in fragment culture with NP-Hy and its structural analogues NIP-Hy and NNP-Hy. The results indicate that the majority of responsive B cells discriminate among these haptenic determinants; however, lambda-bearing B cells responsive to the NP and NIP determinants represent a highly overlapping set of clonotypes. Comparison of the responses to NP-Hy and NIP-Hy of splenic vs sIg- precursors of this clonotype family suggests that the T cell-dependent stimulation of both mature and immature B cells by antigen is highly affinity dependent. Significantly, the affinity thresholds for both stimulation and tolerance induction of immature B cells appears to be higher than that required for the stimulation of mature splenic B cells. Such a disparity in the requisites for triggering mature vs immature B cells could readily account for the presence of low-affinity self-reactive B cells in the mature B cell pools of normal individuals.
Proliferation of phenotypically immature human thymocytes with and without interleukin 2 receptors.
Authors: Piantelli M , Larocca L M , Aiello F B , Maggiano N , Carbone A , Ranelletti F O , Musiani P
Published: December 2022

Previous studies have indicated that the human thymus is composed of several discrete compartments. Cortical thymocytes are reactive with the monoclonal antibody anti-T6, whereas most medullary cells, unreactive with anti-T6, stain brightly with anti-T3, which defines mature T cell populations. Only a minor thymocyte population lacks both T3 and T6 but expresses T11 antigens. Within the thymus, several proliferating lymphoblasts are present. In addition a distinct subset shows the capacity to proliferate in response to mitogens. By continuous Percoll density gradient centrifugation, we have obtained a cell fraction comprising the vast majority of cells able to proliferate spontaneously or after PHA stimulation. By a panning procedure performed with anti-T3 and anti-T6 antibodies, three phenotypically distinct thymocyte subsets were separated from this fraction, and their functional capabilities were tested. The spontaneous proliferating activity was found to be mainly attributable to thymocytes unable to respond to mitogen, expressing the cortical T6 marker and lacking receptors for IL 2. T3-positive cells are able to respond to mitogen. However, these thymocytes are incapable of producing the adequate amount of IL 2 required to fully saturate their intrinsic proliferative capability. Surprisingly, the phenotypically least mature intrathymic T lymphocytes (T3 and T6 negative) respond to phytomitogen, at least in part, in an interleukin-dependent manner. It is noteworthy that a large proportion of these T3- and T6-negative thymocytes express IL 2 receptors and class II MHC antigens without in vitro activation. These novel findings have potential implications in the context of current models of differentiation pathways within the human thymus.
Only the initial binding of cationic immune complexes to glomerular anionic sites is mediated by charge-charge interactions.
Authors: Gauthier V J , Mannik M
Published: December 2022

The role of charge-charge interactions between cationic immune complexes and the anionic sites on the glomerular basement membrane was examined. For this purpose, soluble immune complexes at fivefold antigen excess were prepared with human serum albumin and cationized rabbit antibodies to this protein. When unrelated cationic proteins, protamine sulfate or cationized rabbit serum albumin, were given 1 min before the cationized immune complexes, glomerular immune deposits did not form. Cationic immune complexes allowed to deposit in glomeruli could readily be displaced by protamine sulfate or cationized rabbit serum albumin injected 1 min after the immune complexes. If the same cationic molecules were injected 1 hr after the immune complexes, the complexes could not be displaced from glomeruli. In contrast, cationic complexes that were deposited in glomeruli in the presence of a very high degree of antigen excess in circulation to prevent their condensation into larger complexes in glomeruli were readily displaced at 1 min and 1 hr with protamine sulfate or with cationized rabbit serum albumin. On the basis of these results, we concluded that the initial binding of cationic immune complexes to glomeruli occurs by charge-charge interactions. Once the immune complexes in glomeruli condense to larger deposits, forces other than charge-charge interactions are responsible for their retention in glomeruli.
A 44 kilodalton cell surface homodimer regulates interleukin 2 production by activated human T lymphocytes.
Authors: Martin P J , Ledbetter J A , Morishita Y , June C H , Beatty P G , Hansen J A
Published: December 2022

We previously described a cell surface antigen, termed Tp44, detected by monoclonal antibody 9.3 on approximately 80% of mature human T lymphocytes. Analysis by SDS-polyacrylamide gel electrophoresis and isoelectric focusing demonstrated that this antigen consists of two identical 44 kilodalton glycopeptides that form a disulfide-linked homodimer. Competitive binding experiments showed that antibody 9.3 and an anti-CD3 antibody (64.1) recognize distinct antigenic determinants; furthermore, the binding of antibody 9.3 was unaffected by prior modulation of CD3. Thus, Tp44 has no detectable cell surface association with CD3. By itself, antibody 9.3 had no detectable effect on either IL 2 receptor expression or IL 2 release, and did not cause T cell proliferation even when monocytes were present and exogenous IL 2 was provided, indicating that binding of antibody 9.3 does not provide a primary signal for T cell activation. However, the proliferative responses of T lymphocytes activated by phytohemagglutinin, concanavalin A, or an anti-CD3 monoclonal antibody were strikingly enhanced in the presence of antibody 9.3, an effect associated with increased IL 2 receptor expression and increased IL 2 secretion. Antibody 9.3 enabled anti-CD3-Sepharose-activated T cells and anti-CD3 antibody-activated Jurkat cells to release IL 2 in the absence of monocytes. Fab fragments of antibody 9.3 had no effect on anti-CD3-induced IL 2 release by Jurkat cells, whereas F(ab')2 fragments had activity comparable to that of unmodified antibody, indicating that bivalent binding of Tp44 molecules is required for IL 2 secretion. Together, these results suggest that TP44 may function as a receptor for accessory signals in the activation of T cells.
Contra-IL 2; a suppressor lymphokine that inhibits IL 2 activity.
Authors: Maki T , Satomi S , Gotoh M , Monaco A P
Published: December 2022

Suppressive activity of culture supernatant of AS-9 (AS-9 CS), a T cell hybridoma line that was derived from fusion of BW5147 thymoma and splenic T cells of anti-lymphocyte serum-treated C3H mice, was analyzed. AS-9 CS inhibited allogeneic cytotoxic T lymphocyte (CTL) generation as well as T cell proliferation to alloantigens and mitogens, but failed to inhibit B cell response to lipopolysaccharide or growth of tumor and fibroblast cells. Although addition of AS-9 CS to the allogeneic sensitization culture as late as on day 2 of incubation resulted in maximal inhibiton of CTL generation, removal of AS-9 CS on day 3 of incubation abolished its inhibitory effect. Addition of purified IL 2 together with AS-9 CS to the allogeneic sensitization cultures only partially abrogated the suppression. Experiments with IL 2-dependent cytotoxic T cell line (CTLL) showed that AS-9 CS suppressed the IL 2-induced proliferation of CTLL. Preincubation of AS-9 CS with CTLL removed its inhibitory effect on CTL generation. These results indicate that AS-9 CS interferes with the mechanism of T cell activation by IL 2. On this basis, AS-9 CS was named contra-IL 2.
Epitope and functional specificity of monoclonal antibodies to mouse interferon-gamma: the synthetic peptide approach.
Authors: Russell J K , Hayes M P , Carter J M , Torres B A , Dunn B M , Russell S W , Johnson H M
Published: December 2022

Spleen cells from hamsters immunized with recombinant mouse interferon-gamma (IFN-gamma) were fused with mouse myeloma cells, resulting in the production of four anti-IFN-gamma monoclonal antibodies. Binding of 125I-IFN-gamma by these protein A-bound antibodies was specifically blocked by cold IFN-gamma. Binding by three of these antibodies was also blocked by a synthetic peptide corresponding to the N-terminal 1-39 amino acids of IFN-gamma, whereas a corresponding C-terminal (95-133) peptide had no effect on binding. The N-terminal specificity of these three antibodies was confirmed by their specific binding of 125I-N-terminal (1-39) peptide. One of the N-terminal specific monoclonal antibodies inhibited both antiviral and macrophage priming (for tumor cell killing) activities of IFN-gamma, whereas the other two had no effect on either biologic function. The selectivity of the inhibition of IFN-gamma function was not due to a differential ability of the N-terminal specific antibodies to bind IFN-gamma. Blocking experiments with cold IFN-gamma and N-terminal peptide suggest that the epitope specificities of the monoclonal antibodies could be determined by the conformational or topographic structure of IFN-gamma. An exact determination of the epitope specificity of the monoclonal antibody that inhibited IFN-gamma function could provide insight into the structural basis for the role of the N-terminal domain in the biologic function of IFN-gamma. Polyclonal antibodies to either the N-terminal or the C-terminal peptides also inhibited both the antiviral and the macrophage-priming activities of IFN-gamma. All of the antibodies that inhibited IFN-gamma function also blocked binding of IFN-gamma to membrane receptor on cells, whereas antibodies that did not block function also did not inhibit binding. The data suggest that both the N-terminal and the C-terminal domains of IFN-gamma play an important role in its antiviral and macrophage-priming functions, possibly in a cooperative manner.
Interferon-gamma binds to high and low affinity receptor components on murine macrophages.
Authors: Aiyer R A , Serrano L E , Jones P P
Published: December 2022

Interferon-gamma (IFN-gamma), a glycoprotein secreted by antigen-or mitogen-activated lymphocytes, modulates the activities of lymphocytes and macrophages. For mouse macrophages, murine IFN-gamma (MuIFN-gamma) stimulates several functions, including phagocytosis, tumoricidal activity, and the increased expression of Ia and H-2 antigens of the major histocompatibility complex. Recent reports have suggested that IFN-gamma specifically binds to cell surface receptors corresponding to a single class of binding sites with a Kd of 10(-8) to 10(-10) M. We present evidence that, on the murine macrophage cell line WEHI-3, MuIFN-gamma specifically binds to two classes of binding sites with Kd of 9.1 X 10(-11) M (500 sites/cell) and 2.7 X 10(-9) M (4400 sites/cell). The higher affinity sites most likely represent the physiologically relevant receptors that mediate at least some of the actions of MuIFN-gamma.
Endogenous association of decay-accelerating factor (DAF) with C4b and C3b on cell membranes.
Authors: Kinoshita T , Medof M E , Nussenzweig V
Published: December 2022

Decay-accelerating factor (DAF) is a membrane glycoprotein found on various cells that are in contact with complement. It inhibits the formation of the C3 convertases of the complement system, both the classic (C4b2a) and alternative (C3bBb) pathways. In this investigation, we used a homobifunctional cross-linking reagent to search for a DAF ligand on the surface of cells subjected to complement attack. We found that DAF forms complexes with C4b and C3b deposited on the same erythrocytes, but not with the physiologic degradation products of these complement fragments, that is, C4d or C3dg. Taken together with prior observations that DAF action is reversible, and DAF does not affect the structure of C4b or C3b, these findings suggest that DAF functions by competitively inhibiting the uptake of C2 or factor B, and preventing the assembly of the C3 convertases.