bluuebunny/crossref_metadata_2025 huggingface dataset:
Identification of macrophage receptors for angiotensin: a potential role in antigen uptake for T lymphocyte responses?
Authors: Thomas D W , Hoffman M D
Published: December 2022

To determine if macrophages express receptors for peptide antigens, guinea pig peritoneal exudate cells (PEC) were examined for their uptake of the octapeptide angiotensin II (AII). PEC were incubated with [3H]AII, with or without nonradioactive AII as a cold inhibitor, for varying lengths of time before harvesting to determine the cell-associated [3H]AII counts per minute. The PEC-associated [3H]AII increased from 90 to 120 min of incubation, then plateaued on additional incubation to 3.5 hr. Inclusion of nonradiolabeled AII into the culture decreased the cell-associated [3H]AII by 80 to 90% at all time points. The uptake of [3H]AII was temperature-sensitive, with maximum cell-associated [3H]-AII occurring at 37 degrees C and reduced uptake occurring at 4 degrees C. The association of [3H]AII with PEC was specific and saturable, and the inhibitory dose for reducing the cell-associated [3H]AII by 50% with nonradiolabeled AII was around 6 X 10(-6) M. Various AII analogs were also employed as inhibitors to determine the fine specificity of [3H]AII binding, and only those analogs with nonaromatic amino acid substitutions for the carboxyl terminal Phe8 showed reduced inhibitory activity, indicating that Phe8 is important for binding. Scatchard analysis of binding indicated that two classes of receptors interacted with AII: a low number of receptors with Ka approximately equal to 3.5 X 10(8) M-1, and a large number of relatively low affinity of binding showing a Ka approximately equal to 5 X 10(5) M-1. The cellular binding activity was associated with isolated PEC plasma membranes, and after density gradient fractionation of solubilized membranes, AII binding activity was primarily associated with molecules of m.w. of around 50,000. PEC were separated into macrophages and lymphocytes by adherence, and all of the [3H]AII binding activity was associated with the macrophage-enriched cells. These results show that macrophages express specific receptors for AII and related peptides that are responsible for most of the uptake of AII by macrophages. We discuss the relevance of this receptor for the immunologically important uptake of AII by macrophages, and a potential physiologic role in angiotensin-converting enzyme production.
Genetic control of collagen-induced arthritis in rats: the immune response to type II collagen among susceptible and resistant strains and evidence for multiple gene control.
Authors: Griffiths M M , DeWitt C W
Published: December 2022

We evaluated the cellular and humoral immune response to type II collagen and the relative susceptibility to type II collagen-induced arthritis (CIA) in 14 inbred rat strains representing six RT1 specificities and including four congenic strain pairs differing only at RT1, by using a standard protocol with native calf type II collagen as the immunogen: WF(RT1u) was a high responder and susceptible; RT1c , RT1a , and RT1l strains were intermediate responders and, on a strain basis, were variably susceptible or resistant; RT1b and RT1n strains were low responders and resistant to CIA. An intermediate to high immune response to type II collagen, although associated with CIA, was not sufficient for the induction of clinical arthritis. A high degree of cross-reactivity between calf and rat type II collagen was found. No selective, antigen-specific decrease in immune response to rat type II collagen as compared to calf type II collagen was found in the resistant strains. In six strains, resistance correlated with the expression of public Ia antigens cross-reactive with the public Ia antigens of BN. The non-MHC-linked BN genome also exerted a suppressive effect on the incidence and severity of CIA in strains carrying collagen-responder and CIA-susceptible RT1 alleles. Together, the data show that CIA in rats is under the control of multiple genes, both RT1-linked and nonlinked .
Early mitogen-induced metabolic events essential to proliferation of human T lymphocytes: dependence of specific events on the influence of adherent accessory cells.
Authors: Bruszewski W B , Bruszewski J A , Tonnu H , Ferezy S L , O'Brien R L , Parker J W
Published: December 2022

Adherent accessory cells (AC) are required for the proliferative response of T lymphocytes to antigens and various mitogens. A current model of AC-T cell cooperation is that commitment to growth of mitogen activated T lymphocytes occurs via sequential action of IL 1 and IL 2. Initial mitogen action on T lymphocytes in the presence of AC is followed by a sequence of metabolic changes which culminate in DNA replication and mitosis. Many of these early events are critical to DNA replication. We studied several of these mitogen-induced events in experiments designed to define the specific influence of AC on T cell metabolism before initiation of DNA replication. By using human peripheral T lymphocytes depleted of AC to the extent that the proliferative response is essentially ablated, we found that the sequence of early events is divided into two phases: an early activated state in which certain events are stimulated directly by mitogen and independently of AC, and an AC-dependent state in which other events occur in mitogen-treated lymphocytes only in the presence of the numbers of AC necessary to support the proliferative response. We partially support the proliferative response. We partially characterized the nature of the metabolic activation that pulse neuraminidase-galactose oxidase treatment induces in lymphocytes in the presence and functional absence of AC. Stimulated uptake of [3H] uridine and [3H]-leucine into cellular precursor pools and incorporation into macromolecules apparently requires the presence of AC, but stimulated influx of both [3H]3-O-methyl glucose and [3H]alpha-amino isobutyric acid are independent of the presence of AC. These data suggest that stimulated influx of glucose and a certain class of essential amino acids are events of the early activated state, whereas increased RNA and protein synthesis are events of the AC-dependent state. All of these events are critical to the T cell's commitment of DNA replication and mitosis. The early activated state is consistent with AC-T cell cooperation via IL 2. It is possible that IL 2 mediates passage of IL 2 receptor-bearing T cells from the early activated state to the AC-dependent state, which then leads directly to DNA replication and mitosis.
Isotype-specific human suppressor T cells for IgE synthesis activated by IgE-anti-IgE immune complexes.
Authors: Hassner A , Saxon A
Published: December 2022

The ability of human IgE-anti-IgE (mouse hybridoma anti-Fc) immune complexes (IC) to generate suppressor T cells for human myeloma IgE synthesis in vitro was tested. T cells incubated with 0.1 micrograms/ml of IC that had an IgE to anti-IgE ratio of 1:1 inhibited myeloma IgE synthesis by 16% more than the control (p less than 0.01). Inhibition was also seen with IC in which the IgE to anti-IgE ratio was higher (2:1 and 4:1), but these differences in synthesis were smaller and were not statistically significant (8 and 3%, respectively, p greater than 0.05). Thymidine incorporation by T cells incubated 3 days with 0.1 microgram/ml of IC at the 1:1 or 2:1 ratio was consistently greater (p less than 0.0025 and less than 0.0125, respectively) than by controls. The IC lost their ability to generate suppressor T cells when the cytophilic site on the IgE molecule was destroyed with heat treatment (0% inhibition with IC at 1:1 and 4% inhibition with IC at 2:1). The activation of T cells with IC showed isotype specificity because the activated T cells failed to suppress IgG and IgA synthesis by the lymphoblastoid cell lines GM-1500 and GM-1056, respectively. T cells were fractionated by incubation with IC and then were panned on plates coated with goat anti-mouse IgG. The adherent cells spontaneously suppressed IgE by 25% when compared to controls (p less than 0.005). These cells failed to suppress IgG and IgA. The activation of the T cells was not due to the panning process itself because activation did not occur with cells that adhered to plates coated with bovine serum albumin (p greater than 0.05) when compared to untreated T cell controls or the IC nonadherent population. These experiments extend previous findings that isotype-specific suppressor T cells for IgE synthesis can be generated in vitro.
Antibodies from patients with autoimmune disease react with a cytoplasmic antigen in the Golgi apparatus.
Authors: Fritzler M J , Etherington J , Sokoluk C , Kinsella T D , Valencia D W
Published: December 2022

In this study we report the identification of an antibody in the sera of some patients with autoimmune disease that reacted with a cytoplasmic antigen localized within the Golgi apparatus. The antibody reacted with all tissues investigated, which included pancreas, kidney, testis, liver, thymus, and spleen. In addition, it reacted with some human peripheral circulating lymphocytes, murine peritoneal macrophages, and a variety of tissue culture cell lines, which included HEp-2 cells (human epithelial carcinoma), baby hamster kidney cells, a canine thymus cell line, a primary kidney cell line, Ehrlich ascites cells, Wil-2 cells, and Raji cells. The antigen is located in the same region stained by the histochemical reaction for thiamine pyrophosphatase, thus indicating that the antigen is located within the Golgi apparatus. The antigen was not demonstrated by immunodiffusion of saline extracts of rabbit thymus, pancreas, or liver. The antigen in HEp-2 cells was resistant to RNase A, DNase I, micrococcal nuclease, and to extraction with 0.1 N HC1, but was sensitive to trypsin and Proteinase K. Eight patients with anti-Golgi antibodies have been identified. Six of the eight had systemic lupus erythematosus. Autoantibodies to a Golgi apparatus antigen might serve as a useful biologic marker to study the functional relationship of the Golgi apparatus to lymphocytes and macrophages.
The molecular basis for the difference in immune hemolysis activity of the Chido and Rodgers isotypes of human complement component C4.
Authors: Isenman D E , Young J R
Published: December 2022

Human C4 displays a structural polymorphism which is consistent with there being two closely linked genetic loci coding for this protein. These give rise to two C4 isotypes, designated C4A and C4B, which can be distinguished by charge and apparent m.w. differences in their respective alpha-chains and by the presence or absence of the Chido/Rodgers blood group antigens. Previous qualitative studies of C4 immune hemolysis activity in whole plasma had suggested that the C4B isotype was functionally more active. By using purified C4A and C4B isolated from individual donors known serologically to possess only one of the C4 isotypes, we examined the molecular basis for the differences in their respective hemolytic activities. It was found that the C4B:C4A hemolytic activity ratio was approximately 4:1. This fourfold difference could not be accounted for by a commensurate difference in the cleavage rate of the two isotypes by C1s by differences in the kinetics of assembly or intrinsic decay of the respective C3 convertase enzymes, or by differences in the rate of isotypic C4b cleavage by factor I in the presence of C4bp . However, the fourfold greater deposition efficiency of nascent C4b of the C4B isotype onto the surface of C1-bearing sheep erythrocytes quantitatively accounted for the observed difference in immune hemolysis function. It was further found that the thioester bond of nascent C4b of the C4A isotype preferentially transacylates onto amino group nucleophiles, whereas in the C4B isotype, acylation of hydroxyl groups is strongly preferred. Thus, the difference in immune hemolysis activity between the two C4 isotypes does not necessarily indicate an impairment of function in C4A; it may merely be a reflection of the relative abundance at the surface of a C1-bearing target of hydroxyl and amino groups capable of being acyl acceptors for nascent C4b. Finally, we also present evidence showing that the apparent m.w. difference between the alpha-chains of the C4A and C4B isotypes is not due to differences in protein glycosylation.
Identification of a glycoprotein, gp21, of adult T cell leukemia virus by monoclonal antibody.
Authors: Sugamura K , Fujii M , Ueda S , Hinuma Y
Published: December 2022

A mouse hybridoma cell line producing monoclonal antibody, F10, was established from mice hyperimmunized with cells bearing adult T cell leukemia (ATL) virus (ATLV). F10 antibody reacted with an ATLV structural polypeptide ( gp21 ) with a m.w. of 21,000 that was glycosylated on cell surfaces. The gp21 was expressed on cell surfaces of all ATL-associated antigen (ATLA)-positive human cell lines but not on ATLA-negative cell lines nor peripheral blood leukocytes stimulated with mitogens. The gp21 was also detected with anti-ATLA-positive human serum, and the binding of F10 antibody to ATLA-positive cell surfaces was significantly blocked by pretreatment with anti-ATLA-positive human sera. Double immunofluorescence staining with F10 antibody and anti-ATLA-positive human serum caused co-capping on cell surfaces, which suggests that gp21 co-exists with other ATLV antigens expressed on cell surfaces. Immunoprecipitation studies also suggested that the gp21 is a minor component of the ATLV envelope.
Rapidly expanded activated human killer cell clones have strong antitumor cell activity and have the surface phenotype of either T gamma, T-non-gamma, or null cells.
Authors: van de Griend R J , van Krimpen B A , Ronteltap C P , Bolhuis R L
Published: December 2022

Cloned lymphoid cell lines showing cytolytic activity were derived from natural killer (NK) cell-enriched cell fractions obtained by fluorescence-activated cell sorting of cells that reacted with B73 .1, an NK cell-specific monoclonal antibody (MCA). The clones were cultured for more than 30 generations (i.e., more than 10(9) descendants from a single cell). The rapid expansion was achieved by using a special culture system developed for this purpose and based on the use of two types of allogeneic feeder cells. Three phenotypically different types of cytotoxic clones were obtained. These clones showed a broad spectrum of cytolytic activity against several NK-susceptible and NK-nonsusceptible tumor target cells. One of these clones had the following binding pattern to MCA: B73 .1+, T3-, T4-, T8-, HNK1 -, and Lyt-3-. These cells formed rosettes with IgG-coated erythrocytes but not with sheep erythrocytes, and therefore might be null cell-derived. Most of the cytotoxic clones showed the following phenotype: B73 .1+, T3-, T4-, T8-, HNK1 -, Lyt-3+, E+, and EA-gamma +. These clones were probably derived from T-gamma cells. In addition, one clone with cytolytic activity was derived from B73 .1- cells. This had the phenotype B73 .1-, T3+, T4-, T8-, HNK1 -, Lyt-3+, E+, and EA-gamma-, and may be of T-non-gamma cell origin. About 10 noncytolytic clones showed the phenotype B73 .1-, T3+, T4, or T8+, HNK1 -, Lyt-3+, Ia+, E+, and EA-gamma -. An absolute correlation was found between the presence of the B73 .1 antigen, the absence of the T3 marker, and the capacity of the cells to form EA rosettes. Furthermore, all clones except one (Lyt-3-) formed E rosettes. Although the in vitro life span varied from clone to clone, B73 .1- clones generally grew faster and for longer times (greater than or equal to 50 generations) than did B73 .1+ ones (less than or equal to 40 generations). The cytolytic activity, cell surface phenotype as determined with MCA, rosette formation, and target cell specificity spectrum remained stable over the entire culture period. We conclude that the majority of the activated MHC-nonrestricted cytolytic clones obtained in this culture system show a particular phenotype. These cells can be expanded to large numbers. Whether or not these clones might be derived from B73 .1+, HNK1 + NK cells with the morphologic appearance of large granular lymphocytes will be discussed.
Human in vivo antigen-induced lymphoblastoid B cells are capable of cyclical antibody production in vitro.
Authors: Brieva J A , Stevens R H
Published: December 2022

In vivo immunization of normal volunteers with tetanus toxoid induces the formation of a circulating B cell subset that has the capacity to secrete specific antibody in vitro without the need for T cell help or mitogen stimulation. From earlier studies it was not clear whether the spontaneous antibody-secreting lymphoblastoid (LB) B cell was at a terminal stage of differentiation or if it had the capacity to give rise to additional B cell subsets, such as memory cells or more fully mature antibody-producing cells. In this study we have shown that at least two distinct waves of spontaneous antibody secretion can occur in vitro when cultures are initiated with the lymphocytes from individuals immunized 6 days earlier. The first production of antibody was completed by 3 days of in vitro culture and the second production of antibody did not initiate until day 7 or 8 of culture and was completed by day 12. The B cells responsible for the second stage of antibody production appeared derived from a portion of the antibody-secreting cells present on day 3 in that 1) treatment of the cultures on day 0 with BuDr and light equally inhibited the first and second rounds of antibody synthesis; 2) when isolated from the blood, both B cell subsets were in the large cell fraction after 1 X G sedimentation; and 3) under conditions of limiting numbers of cells, the cells responsible for the second wave of antibody production were almost exclusively found in cultures positive for a B cell that had produced antibody on days 1 to 3. Although only a portion (10 to 30%) of the LB B cells present on day 0 had the capacity to again produce antibody on days 8 to 12, the two cells were capable of producing similar quantities of antibody on a per cell basis. These results indicate that the mature circulating LB cell induced in vivo by immunization is not terminally differentiated, but under appropriate conditions has the capacity to give rise to additional antibody-secreting cells.
Antigenic analysis of hematopoiesis. III. A hematopoietic progenitor cell surface antigen defined by a monoclonal antibody raised against KG-1a cells.
Authors: Civin C I , Strauss L C , Brovall C , Fackler M J , Schwartz J F , Shaper J H
Published: December 2022

The anti-My-10 mouse monoclonal antibody was raised against the immature human myeloid cell line KG-1a and was selected for nonreactivity with mature human granulocytes. Anti-My-10 immunoprecipitated a KG-1a cell surface protein with an apparent Mr of approximately 115 kD. We describe the binding of this antibody to human hematopoietic cell types and show that My-10 is expressed specifically on immature normal human marrow cells, including hematopoietic progenitor cells. My-10 is also expressed by leukemic marrow cells from a subpopulation of patients. Thus, this antibody allows the identification and purification of hematopoietic progenitor cells from normal human marrow and the subclassification of leukemia.
Mononuclear cell-mediated enhancement of granulocyte function in man.
Authors: Vadas M A , Nicola N , Lopez A F , Metcalf D , Johnson G , Pereira A
Published: December 2022

Human monocyte-enriched mononuclear cells (MNC) (greater than 95% monocytes) powerfully stimulated the antibody-dependent killing of tumor cells by purified human neutrophils (NE) or eosinophils (EO). The enhancement was observed when the mononuclear cell to granulocyte ratio was as low as 1:100. Media conditioned by MNC also stimulated antibody-dependent killing by NE and EO as well as the uptake and killing of Candida albicans by NE. There was a heterogeneity amongst individuals in the capacity of their MNC to elaborate this factor, and approximately 15% of individuals did not produce detectable factor. Different factors in the MNC supernatant were involved in NE and EO activation. The EO-activating factor (AF) had a m.w. of approximately 27,000 and migrated as a single band on phenyl-Sepharose chromatography. The NE-AF had a m.w. of 22,000 and migrated as two distinct bands on phenyl-Sepharose chromatography. EO-colony-stimulating factor (CSF) co-purified with EO-AF, and granulocyte-macrophage-CSF co-purified with both bands of NE-AF. It is concluded that MNC elaborate CSF-like molecules that powerfully stimulate human granulocyte function.
Nutritional factors and autoimmunity. IV. Dietary vitamin A deprivation induces a selective increase in IgM autoantibodies and hypergammaglobulinemia in New Zealand Black mice.
Authors: Gershwin M E , Lentz D R , Beach R S , Hurley L S
Published: December 2022

The role of nutrition in modulating autoantibody expression in murine lupus has become well documented. One such nutritional factor, zinc deficiency, has received significant attention because of the well-known effects of zinc on the immune function of genetically normal animals. Moreover zinc-deficient diets retard autoantibody production in NZB, NZB/W, and MRL/1 mice; such deprivation also enhances survival in all three strains. Because zinc nutriture influences vitamin A metabolism, it has been postulated that the immunologic effects of zinc deficiency are mediated in part by the reduction of vitamin A levels seen in zinc deprivation. To explore this possibility we studied the influence of vitamin A deficiency, in zinc well-nourished mice, on autoantibody production in NZB mice. Groups of NZB mice, beginning at 6 mo of age, were fed a vitamin A-deficient diet or a control diet ad libitum or pair-fed to the deficient group. The diet contained casein as the protein source and contained adequate levels of trace elements and vitamins. Despite our hypothesis that the reduction of autoantibodies in zinc-deficient NZB mice might be mediated by secondary vitamin A deficiency, we found that vitamin A-deficient animals manifested more severe hypergammaglobulinemia and an earlier onset of both NTA and IgM anti-erythrocyte autoantibodies than did vitamin A-sufficient mice. These results illustrate the importance of rigorous studies of select nutritional parameters and warn of the possibility of clinical harm in feeding inappropriate diets to patients with systemic lupus erythematosis.
Phenotypic characterization of human T lymphocyte populations producing macrophage-activating factor (MAF) lymphokines.
Authors: Biondi A , Roach J A , Schlossman S F , Todd R F
Published: December 2022

Human T lymphocytes, which are known to produce lymphokines that can activate monocytes and macrophages, can be subdivided into two functionally relevant subsets, as indicated by the expression of the T4 and T8 antigens. To determine whether one or both of these T cell subsets is capable of generating macrophage activating factor(s) (MAF) after stimulation with lectin, soluble antigen, or cell surface alloantigen, highly purified populations of T4 or T8 cells were cultured in medium containing PHA, tetanus toxoid-soluble antigen, or allogeneic B lymphoblastoid cells. The resultant culture supernatants were tested for the presence of MAF activity, as manifested by the activation of human peripheral blood monocytes to perform enhanced cytotoxicity and cytostasis against a murine tumor cell line, or to perform antibody-dependent cytotoxicity against anti-RhD-coated human erythrocytes. Both isolated T4 or T8 cells were able to produce MAF activity after stimulation with either PHA or alloantigens, but only the T4 subset generated MAF in response to stimulation with tetanus toxoid. These results coincide with the proliferative capacity of the isolated T subsets to respond to the same stimulators, and demonstrate that the ability to generate MAF lymphokines is not subset restricted.
LPS regulation of the immune response: Bacteroides endotoxin induces mitogenic, polyclonal, and antibody responses in classical LPS responsive but not C3H/HeJ mice.
Authors: Wannemuehler M J , Michalek S M , Jirillo E , Williamson S I , Hirasawa M , McGhee J R
Published: December 2022

Recent studies have suggested that lipopolysaccharide (LPS) derived from gram-negative organisms such as Bacteroides, which are not members of the Enterobacteriaceae, stimulate B cells from the classic LPS-hyporesponsive C3H/HeJ mouse. In the present study, purified, phenol-water-extracted LPS from Bacteroides fragilis ATCC 25285 (B-LPS) was tested for its ability to induce in vivo and in vitro responses in classic LPS-responsive C3H/HeN, LPS-hyporesponsive C3H/HeJ, and (C3H/HeN X C3H/HeJ)F1 hybrid mice. B-LPS induced mitogenic responses in both C3H/HeN and C3H/HeJ spleen cell cultures when cells were cultured under standard conditions, i.e., 8 X 10(5) cells/well. Interestingly, when lower spleen cell numbers were tested with B-LPS, a typical responsive-nonresponsive pattern developed in which good mitogenic responses were induced by B-LPS in C3H/HeN cultures and in which low responses in C3H/HeJ spleen cell cultures were evident. In vivo immunization of mice with B-LPS resulted in high antibody responses in C3H/HeN, intermediate responses in F1, and low responses in C3H/HeJ mice. When purified splenic B cells were incubated with B-LPS, both mitogenic responses and polyclonal immunoglobulin M (IgM) synthesis occurred in C3H/HeN cultures, whereas intermediate responses were noted in F1 cultures and no response was seen in B cell cultures from C3H/HeJ mice. Furthermore, in vitro TNP-B-LPS responses were induced in C3H/HeN spleen cells or purified B cell cultures, and intermediate anti-TNP PFC responses occurred in F1 spleen cells or purified B cell cultures. The toxicity of B-LPS was tested in galactosamine-sensitized mice. The LD50 values for B-LPS in classic LPS-responsive C3H/HeN and C57BL/6J mice were 0.6 microgram and 1.1 microgram, respectively; F1 hybrid mice were approximately 15-fold more resistant, whereas C3H/HeJ mice gave an LD50 of 1650 micrograms. This study shows that phenol-water preparations of B-LPS are biologically active and induce responses in the classic LPS-responsive but not in the LPS-hyporesponsive C3H/HeJ mouse strain.
Association of Rho(D) polypeptides with the membrane skeleton in Rho(D)-positive human red cells.
Authors: Gahmberg C G , Karhi K K
Published: December 2022

The Rho(D) antigen was recently identified as a 28,000 to 33,000 m.w. polypeptide expressed on the surface of human Rho(D)+ cells. We now show that 70 to 80% of the Rho(D) polypeptides remain firmly associated with the membrane skeleton (detergent-insoluble matrix) obtained after treatment of isolated membranes with Triton X-100. The same treatment solubilized most of the major sialoglycoprotein, glycophorin A. The membrane skeleton-bound Rho(D) polypeptides were not solubilized by procedures that dissociated spectrin, actin, and glyceraldehyde-3-phosphate dehydrogenase from the membrane. Affinity-purified 125I-labeled anti-Rho(D) antibodies bound to intact Rho(D)+ cells, Rho(D)+ membranes, and isolated membrane skeletons from Rho(D)+ cells, but not to Rho(D)- cells. The binding to Rho(D)+ cells was competitively inhibited efficiently by Rho(D)+ membranes and weakly by Rho(D)- membranes. When isolated unsealed Rho(D)+ and Rho(D)- membranes were labeled by lactoperoxidase-catalyzed iodination and solubilized in Triton X-100, Rho(D) polypeptides were immune precipitated only from Rho(D)+ membranes.
Comparison of membrane IgM expression in the murine B cell lymphoma 70Z/3 treated with LPS or supernatant containing T cell factors.
Authors: Weeks R S , Mains P E , Sibley C H
Published: December 2022

The cultured murine B cell lymphoma, 70Z /3, can be induced to express membrane IgM ( mIgM ) after exposure to lipopolysaccharide (LPS) or T cell-derived factors. The kinetics and magnitude of the responses have been compared in wild type 70Z /3 cells and three variants by using flow cytometric analysis and immunoprecipitation. Wild type 70Z /3 cells respond to LPS more quickly and with twofold greater mIgM than to concanavalin A-induced spleen cell supernatant (CAS). Variants were selected for their abnormal mIgM expression in response to LPS, but individual variants also showed normal, aberrant, or no response to CAS. When cells were induced with suboptimal amounts of LPS and CAS, a synergistic effect on the magnitude of mIgM expression was seen in wild type and variant cells. This suggests that both inducing agents are utilizing some part of a common inductive mechanism. The different responses of the variant cell lines will allow further genetic dissection and comparison of the mIgM expression pathways used in response to LPS and CAS.
IgE-binding factors from mouse T lymphocytes. II. Strain differences in the nature of IgE-binding factor.
Authors: Uede T , Ishizaka K
Published: December 2022

Normal spleen cells from high IgE responder, BDF1 mice, formed IgE-potentiating factor upon incubation with mouse IgE, whereas those from low IgE responder, SJL mice, formed IgE-suppressive factor. The majority of the factors from BDF1 spleen cells had affinity for lentil lectin; those from SJL mice lacked affinity for the lectin. BDF1 spleen cells could be switched, however, to form IgE-suppressive factor if the cells were incubated with IgE in the presence of lipomodulin , a phospholipase inhibitory protein. In contrast, SJL spleen cells could form IgE-potentiating factor in the presence of lysolecithin, which enhances the glycosylation of IgE-binding factors. When the two strains were primed with alum-absorbed ovalbumin and their spleen cells were stimulated with homologous antigen, IgE-binding factors were detected in culture filtrates. The factors formed by BDF1 spleen cells selectively potentiated the IgE response, however, whereas those formed by SJL spleen cells selectively suppressed the response. Analysis of the cellular mechanisms for the selective formation of IgE-potentiating factor by antigen-primed BDF1 spleen cells revealed that antigenic stimulation of Lyt-1+ T cells resulted in the formation of two T cell factors, i.e., an "inducer" of IgE-binding factor and a glycosylation-enhancing factor, and that these factors induced the selective formation of IgE-potentiating factor. In SJL spleen cells, antigenic stimulation of Lyt-1+ T cells resulted in the formation of an "inducer" and a glycosylation-inhibiting factor, and those factors in turn stimulated the formation of IgE-suppressive factor. An additional difference between the two strains was found in Fc gamma R+ Ly-1+ T cells that were the cell source of IgE-binding factors. Upon stimulation with IgE or "inducer", BDF1 Lyt 1+ cells formed IgE-potentiating factor, whereas the same subset of T cells from SJL mice formed IgE-suppressive factor. The results indicate that the genetic differences between the two strains with respect to the nature of IgE-binding factors appear to be expressed in the process of glycosylation of IgE-binding factors.
Monoclonal anti-mouse macrophage antibodies recognize the globular portions of C1q, a subcomponent of the first component of complement.
Authors: Heinz H P , Dlugonska H , Rüde E , Loos M
Published: December 2022

One of seven monoclonal antibodies generated against mouse macrophages (M phi) was found to recognize isolated heterologous C1q. This antibody was shown to be cytotoxic and to react in a strain-independent way with mouse M phi derived from bone marrow cells as well as with M phi from the peritoneal cavity; it did not react, however, with mouse granulocytes, thymocytes, or T and B lymphocytes. The hemolytic activity of fluid phase C1q was inhibited to 50% at a 2 X 10(-4) dilution of hybridoma supernatant, whereas a 100-fold higher concentration was required to inhibit C1q bound to immune complexes ( EAC1q ) to the same extent. It was demonstrated that this antibody recognizes the isolated globular, Fc-binding portions of the C1q molecule and reacts with the A and B chains. Because M phi have been shown to synthesize C1q, the Fc-recognizing subcomponent of the first component of complement, evidence was provided that endogeneous C1q can serve as an Fc receptor on M phi during secretion. This fact was demonstrated by a dose-dependent inhibition of Fc-receptor activity for EIgG by the F(ab')2 fragment of this monoclonal antibody. These experiments further support the concept that C1q produced by M phi functions on the surface as an Fc-recognizing molecule before it is released and incorporated into the macromolecular complex of serum C1.
Inhibition of human lymphocyte natural cytotoxicity and antibody-dependent cell-mediated cytotoxicity by K-76 COONa, a reagent that blocks complement activity.
Authors: Hudig D , Redelman D , Minning L , Carine K
Published: December 2022

K-76 COONa is a 440 m.w. fungal product that can inhibit complement activity of C5 and Factor I. K-76 COONa abrogated both human natural killer (NK) cell activity and antibody-dependent cell-mediated cytotoxicity (ADCC) (ID50 approximately 1.5 mM). To be effective, K-76 COONa had to be present during the assay, because pretreatment of lymphocytes with highly inhibitory concentrations of K-76 COONa did not inhibit cytolysis. The monocarboxylic K-76 derivative was more inhibitory to NK than the dicarboxylic derivative. This relative efficacy is similar to that observed for inhibition of complement lysis. K-76 COONa inhibited NK when added before NK conjugate formation, but had little effect when added after conjugate formation. The compound also inhibited the formation of conjugates by NK and K cells. Therefore, this reagent selectively affected events that occurred between the initial effector-target cell interactions and the formation of stable conjugates. It had little influence on the post-binding "lethal hit" stage of cytolysis. These data imply a) that if any molecules similar to C5 are activated during the "lethal hit" stage of cytolysis, then they are inaccessible to K-76 COONa , and b) that C3bi-like molecules may be involved in lymphocyte binding.
Isolation and partial characterization of messenger RNA, from murine T cell hybrids, coding for suppressive immunoglobulin G-binding factor.
Authors: Vaqero C , Fridman W H , Moncuit J , Provost M A , Falcoff E , Gelabert M J , Neauport-Sautes C
Published: December 2022

Poly A RNA has been isolated from a murine T cell hybridoma ( T2D4 ) that spontaneously secretes suppressive immunoglobulin G-binding factor ( IgGBF ). Translation products, obtained from a rabbit reticulocyte lysate translation system and after injection into Xenopus laevis oocytes, contain material with the biologic activity, the affinity, and the m.w. of murine IgGBF ; it suppresses secondary in vitro IgG antibody production in a dose-dependent fashion. The suppressive factor binds to IgG but not to IgM immunoadsorbents and, after mild NaDodSO4 treatment, dissociates in NaDodSO4 polyacrylamide gels into two peaks at 78 and 40 kD. Translation products from two non- IgGBF -secreting cell lines (BW-5147, a T lymphoma line, and A9, a fibroblast cell line) fail to exert any suppressive activity. On sucrose gradients, the RNA responsible for the biologic activity was found in one major peak located at 11S. IgGBF synthesized in a cellfree translation system by using poly A RNA and sucrose gradient fractions was also characterized by immunoprecipitation with Fc fragments of [35S]methionine-labeled proteins. On NaDodSO4 polyacrylamide gels, it migrates in one peak located at 37 kD. We conclude that IgGBF is coded for by 11S poly A RNA and that no post-translational modifications (other than proteolytic cleavage) are necessary to obtain a biologically active factor with Ig-binding properties.
Establishment of a tumor-specific immunotherapy model utilizing TNP-reactive helper T cell activity and its application to the autochthonous tumor system.
Authors: Fujiwara H , Aoki H , Yoshioka T , Tomita S , Ikegami R , Hamaoka T
Published: December 2022

Preinduction of potent hapten-reactive helper T cell activity and subsequent immunization with hapten-coupled syngeneic tumor cells result in enhanced induction of tumor-specific immunity through T-T cell collaboration between anti-hapten helper T cells and tumor-specific effector T cells. On the basis of this augmenting mechanism, a tumor-specific immunotherapy protocol was established in which a growing tumor regresses by utilizing a potent trinitrophenyl (TNP)-helper T cell activity. C3H/He mice were allowed to generate the amplified (more potent) TNP-helper T cell activity by skin painting with trinitrochlorobenzene (TNCB) after pretreatment with cyclophosphamide. Five weeks later, the mice were inoculated intradermally with syngeneic transplantable X5563 tumor cells. When TNCB was injected into X5563 tumor mass, an appreciable number of growing tumors, in the only group of C3H/He mice in which the amplified TNP-helper T cell activity had been generated were observed to regress (regressor mice). These regressor mice were shown to have acquired tumor-specific T cell-mediated immunity. Such immunity was more potent than that acquired in mice whose tumor was simply removed by surgical resection. These results indicate that in situ TNP haptenation of the tumor cells in TNP-primed mice can induce the enhanced tumor-specific immunity leading to the regression of a growing tumor. Most importantly, the present study further investigates the applicability of this TNP immunotherapy protocol to an autochthonous tumor system. The results demonstrate that an appreciable percent of growing methylcholanthrene-induced autochthonous tumors regressed by the above TNP immunotherapy protocol. Thus, the present model provides an effective maneuver for tumor-specific immunotherapy in syngeneic transplantable as well as autochthonous tumor systems.
Lyt-2- T cell-independent functions of Lyt-2+ cells stimulated with antigen or concanavalin A.
Authors: von Boehmer H , Kisielow P , Leiserson W , Haas W
Published: December 2022

Approximately 30% of cytolytic Lyt-2+ clones from primed mice are able to proliferate autonomously, i.e., independent of IL 2 derived from Lyt-2- cells after antigenic stimulation. H-2K- or -D-restricted induction of Lyt-2+ cells to autonomous proliferation requires Ia+ stimulator cells. A strict correlation was observed between the ability of Lyt-2+ clones to proliferative autonomously and to induce DH. Eventually, the growth of all Lyt-2+ cytolytic clones becomes dependent on exogenous IL 2, and their ability to induce DH is lost. Small Lyt-2+ cells can also be induced in primary cultures by antigen or concanavalin A to proliferate in the absence of exogenous IL 2. The frequency of autonomously proliferating small Lyt-2+ cells is the same as that of small Lyt-2+ cells proliferating in the presence of exogenous IL 2. IL 2 derived from Lyt-2- cells can augment proliferation of Lyt-2+ cells, but is not obligatory.
In vivo administration of anti-I-A antibody induces the internalization of B cell surface I-A and I-E without affecting the expression of surface immunoglobulin.
Authors: Fultz M , Finkelman F D , Mond J J
Published: December 2022

Injection of a hybridoma anti-Ia antibody into adult mice results in a dramatic reduction in the expression of B cell sIa without affecting the expression of sIgD or sIgM. This anti-Ia-mediated modulation of B cell sIa occurs within 3 hr and attains it maximum effect within 18 hr after injection of antibody. There is a rapid reexpression of B cell Ia when such sIa- B cells are cultured in vitro. Culture of B cells in vitro with anti-Ia antibody has no discernible effect on the expression of B cell sIa, nor does it prevent the reexpression of sIa on sIa- B cells obtained from anti-Ia-injected mice. Injection of anti-I-A antibody suppresses the expression of both I-A and of I-E, and similarly, injection of anti-I-E suppresses the expression of B cell I-E and I-A antigens. When fluorescein-labeled monoclonal anti-I-A antibody is injected into mice, a significant fraction of B cell sIa can be demonstrated to be internalized by the B cell. The potential immunologic significance of this phenomena of anti-Ia-mediated modulation of B cell sIa is discussed.
Plasmodium berghei sporozoites are mitogenic for murine T cells, induce interferon, and activate natural killer cells.
Authors: Ojo-Amaize E A , Vilcek J , Cochrane A H , Nussenzweig R S
Published: December 2022

Enhanced natural killer (NK) activity was detected in the spleens of mice as early as 24 hr after single i.v. inoculation with gamma-irradiated Plasmodium berghei sporozoites. The activity peaked at 48 hr post-injection, and declined below baseline level by day 8. Reinoculation of mice with irradiated sporozoites produced an increased NK activity significantly smaller than the original activity. Spleen cells sensitized in vivo as well as nonsensitized spleen cells stimulated in vitro with sporozoites produced high levels of interferon (IFN) and displayed enhanced NK activity. Characterization of the IFN through the use of specific antibodies revealed that it was mainly IFN-gamma. The cellular basis for IFN-gamma induction was linked to the mitogenicity of P. berghei sporozoites for T cells. The possibility exists that IFN-gamma may have a regulatory effect on antibody production against P. berghei sporozoites.
Dissociation of severe lupus-like disease from polyclonal B cell activation and IL 2 deficiency in C3H-lpr/lpr mice.
Authors: Davidson W F , Roths J B , Holmes K L , Rudikoff E , Morse H C
Published: December 2022

The lymphoproliferation characteristic of all strains of mice homozygous for the gene lpr results from the expansion of an unusual subset of cells that express reduced levels of Ly-1 and Thy-1 antigens and high levels of Ly-5(B220), an antigen that is normally only detected on cells of the B lineage. In the present study, C3H-lpr mice were studied to determine when this population of cells first appears in lymph node (LN) and spleen and whether its appearance relates to the development of B cell activation and deficiencies in interleukin 2 (IL 2) production. The results showed that Ly-5(B220)+, sIg- cells were first detected in LN at 4 wk of age; thereafter their numbers increased exponentially until at 16 wk of age they represented more than 80% of LN cells. Two subpopulations of Ly-5(B220)+, sIg- cells were present in LN; one Ly-1+, Thy-1+ and the other Ly-1+, Thy-1-. Ly-5(B220)+, sIg- cells were not detected in C3H-lpr spleen until 6 to 10 wks after their appearance in LN, and their proportions never reached those in LN. Polyclonal B cell activation in C3H-lpr spleens was not observed until Ly-5(B220)+, sIg- cells were present, suggesting that this population may play a role in B cell stimulation. IL 2 production by C3H-lpr spleen and LN cells was normal up to 6 wk of age and was significantly impaired thereafter, with LN being more severely affected than spleen. The IL 2 defect could be significantly repaired by the addition of PMA to the cultures. Although defective IL 2 production coincided with the appearance of Ly-5(B220)+, sIg- cells in LN, it preceded the appearance of these cells in spleen. In spite of the impaired ability to produce IL 2 in vitro, CTL responses to alloantigens were normal. Although C3H-lpr mice share many of the lymphoid abnormalities observed in MRL-lpr mice, they do not develop severe, early-onset SLE-like disease characteristic of the latter strain. This suggests that factors other than defective IL 2 production and polyclonal B cell activation are required for the development of fulminant autoimmune disease.
Generation of human C3a, C4a, and C5a anaphylatoxins by protein A of Staphylococcus aureus and immobilized protein A reagents used in serotherapy of cancer.
Authors: Langone J J , Das C , Bennett D , Terman D S
Published: December 2022

Protein A (SpA) alone or immobilized on bacteria (e.g., Cowan strain I), collodion charcoal, or on Sepharose have been used in serotherapy of cancer in humans and experimental animals. Because SpA forms complexes with IgG that can activate complement, and the physiologic response during treatment often involves hypocomplementemia and reactions that are similar to those induced by anaphylatoxins, we used sensitive and specific radioimmunoassays to test the ability of SpA reagents to generate C3a, C4a, and C5a from human serum. The yield of anaphylatoxins depended on the dose of SpA, with the maximum generation of C3a (47 to 55 micrograms/ml) and C5a (1.4 to 1.9 micrograms/ml) being produced with levels of SpA that were maximally precipitated from serum. Maximum C4a levels (up to 15 micrograms/ml) were obtained at concentrations of SpA equal to or greater than the dose required to give optimal precipitation. The maximum concentrations of anaphylatoxins correspond to essentially quantitative conversions of C3 to C3a, C4 to C4a, and 40% of C5 to C5a after correction for levels found in serum incubated in pyrogen-free saline. Preformed insoluble complexes prepared from either serum or monomeric IgG also were capable of generating anaphylatoxins in fresh whole serum up to levels approximately equal to those observed in serum treated directly with an optimal amount of SpA. The preformed complexes from serum or IgG generated similar high concentrations of anaphylatoxins when carried through four sequential incubations with fresh serum, and complexes that contained approximately 1 microgram SpA were still active. Preincubating the insoluble complexes with chicken anti-SpA serum did not alter their activity. Incubation of serum with collodion charcoal coated with SpA, in a system that models the perfusion technique used to treat cancer, produced complexes that generated significant levels of C3a compared with levels found in serum passaged over albumin charcoal or in untreated serum. The C3a levels in serum from the albumin collodion charcoal were not significantly different from those found in untreated serum. Similar amounts of C3a, C4a, or C5a were observed in serum incubated with differing numbers of bacteria representing a strain of S. aureus rich in cell bound SpA (Cowan strain I) or a strain (Wood 46) deficient in SpA. This suggests that in intact bacteria, cell wall factors other than SpA (e.g., peptidoglycan) are predominantly responsible for generating anaphylatoxins.(ABSTRACT TRUNCATED AT 400 WORDS)
Quantitative analysis of Fc gamma receptors on murine spleen cell populations by using dual parameter flow cytometry.
Authors: Titus J A , Finkelman F D , Stephany D A , Jones J F , Segal D M
Published: December 2022

The expression of Fc gamma R on subsets of mouse spleen cells was examined by dual parameter flow microfluorometry. B cells were detected by labeling them with antibodies against sIgM, sIgD, sIgG, or I-A; essentially all B cells expressed Fc gamma R. The number of Fc gamma R per cell on the sIgD+, sIgM+, and I-A+ cells averaged 2 X 10(4) receptors, and no correlation between the levels of expression of Fc gamma R and the B cell markers was evident. The sIgG+ B cells, however, expressed more Fc gamma R (8 X 10(4) receptors/cell) than sIgM+ and sIgD+ B cells. Fc gamma R on splenic macrophages were examined by double labeling spleen cells for Fc gamma R and Mac-1. The Mac-1+ cells (2 to 16% of the spleen cells) were 100% Fc gamma R+ and expressed threefold to fivefold higher numbers of Fc gamma R per cell than the sIgM+ or sIgD+ B cells. The Fc gamma R on T cells were studied on cells double labeled for Fc gamma R and Thy-1, Lyt-1, or Lyt-2. An average of 20% of the T cells expressed Fc gamma R and at least two subsets of Fc gamma R+ T cells were evident: Lyt-2- cells, most of which expressed intermediate (2 X 10(4) Fc gamma R/cell) levels of Fc gamma R, and Lyt-2+ cells, which expressed mainly high (8 X 10(4) Fc gamma R/cell) amounts of Fc gamma R. The levels of expression of Fc gamma R and sIgM increased dramatically in response to infection and were elevated in mice with genetic defects. We conclude that the level of Fc gamma R expression is a characteristic property of subsets of spleen cells from normal and infected mice.