bluuebunny/crossref_metadata_2025 huggingface dataset:
Cell-mediated lympholysis responses against autologous cells modified with haptenic sulfhydryl reagents. IV. Self-determinants recognized by wild-type anti-H-2Kb and H-2Db-restricted cytotoxic T cells specific for sulfhydryl and amino-reactive haptens are absent in certain H-2 mutant strains.
Authors: Levy R B , Shearer G M
Published: December 2022

Virus-specific H-2-restricted cytotoxic T cells (CTL) have been found to discriminate between wild-type and mutant class I molecules. The only results reported concerning a hapten-self model, however, indicate that TNP-specific CTL do not discriminate between wild-type and mutant self determinants (7). In the present study, hapten-specific CTL generated against N-iodoacetyl-N'-(5-sulfonic-1-naphthyl) ethylene diamine-modified syngeneic cells (AED-self) were used to determine whether a hapten that is known to react with different cell surface sites than TNP can induce CTL that distinguish mutant H-2K and D molecules from those of wild type. The findings of this study indicate that H-2Kb-AED-self cytotoxic effector cells can discriminate between self-determinants of H-2Kb wild-type and the H-2bm1 and H-2bm11 mutants, but not between wild-type and the H-2bm6 and H-2bm9 mutants. H-2Db-AED-self effector cells were also found to discriminate between self-determinants of H-2Db wild-type and the H-2bm13 and H-2bm14 mutants. Furthermore, cold target competition experiments indicated that the bm1 and bm11 Kb products also lack some determinants recognized by anti-wild-type Kb TNP-specific CTL. These findings provide the first demonstration that hapten-self-specific effectors can detect alterations in H-2 mutant class I molecules. The results in the present report also support the hypothesis that haptens do not have to derivatize H-2 molecules in order to form antigens recognized by H-2-restricted CTL. These findings are discussed with respect to the involvement of self-determinants on MHC and non-MHC cell surface molecules.
T cell subsets in allograft rejection. In situ characterization of T cell subsets in human skin allografts by the use of monoclonal antibodies.
Authors: Bhan A K , Mihm M C , Dvorak H F
Published: December 2022

We have provided evidence that both major T cell subsets, T4-positive (helper/inducer) and T8-positive (cytotoxic/suppressor), infiltrate human skin allografts. Overall, and in the graft dermis and graft bed, T4-positive cells were predominant (1.5 to 3 times more numerous than T8-positive cells). In contrast, T8-positive cells were relatively more numerous in the epidermis and hair follicles. Rejection probably proceeded by two apparently independent pathways: 1) direct contact killing of graft epithelial cells, presumably by immunologically specific T8-positive cytotoxic cells, and 2) injury of microvascular endothelium of both the graft and graft bed with secondary graft infarction. Although important in first set skin allograft rejection, the mechanism of the second type of killing is uncertain. T4-positive cells were probably involved, as evidenced by their greater numbers; furthermore, studies in mice have shown that transfused helper/inducer cells are able to effect first-set skin graft rejection. It remains to be determined whether T4-positive cells act alone or cooperate with other cells to destroy vessels and bring about graft rejection. Langerhans cells were recognized in epithelial and dermal compartments of both allografts and autografts by their reactivity with anti-T6 and anti-Ia antibodies. We could not determine whether such cells in allografts were of host or donor origin.
Functional characteristics of a Ficoll-separated mouse bone marrow cell population involved in skin allograft prolongation.
Authors: Gozzo J J , Crowley M , Maki T , Monaco A P
Published: December 2022

Treatment of recipient mice with donor bone marrow cells and anti-lymphocyte serum (ALS) results in extensive skin graft prolongation beyond that achieved in animals given only ALS. In this study, B6AF1 recipient mice were grafted with C3H/He skin on day 0, treated with ALS on days -1 and +2 and infused on day +7 with donor strain (C3H/He) bone marrow cells. Extensive graft prolongation was achieved either with 25 X 10(6) whole bone marrow cells or with 1 X 10(6) lymphoid-like cells derived from donor marrow that sediment at a rate of 3 mm/hr in a 2 to 4% Ficoll gradient at unit gravity. These allograft-prolonging lymphoid-like cells appear not to be CFUs cells, have suppressive activity in in vitro MLC assays, and contain both nylon wool adherent and non-adherent cells. These studies thus show that allograft promoting cells can be isolated from bone marrow utilizing Ficoll gradients. Functional studies suggest that 3 mm/hr sedimenting donor bone marrow suppressor cells may be involved in the induction of allograft prolongation.
Actin polymerization induced by chemotactic peptide and concanavalin A in rat neutrophils.
Authors: Rao K M , Varani J
Published: December 2022

Changes in the state of actin in rat neutrophils were studied after chemotactic peptide and concanavalin A stimulation by using the DNase I inhibition assay. Actin polymerization occurred within seconds after stimulation with F-Met-Leu-Phe and concanavalin A. Pretreatment of cells with cytochalasin D prevented chemotactic peptide-induced actin polymerization. The addition of F-Met-Leu-Phe to lysed cells did not produce any change in actin state. These data offer strong evidence for receptor-induced actin polymerization and support the models implicating actin microfilament formation as a crucial event in cell activation. The observations on platelets, lymphocytes, neutrophils, and islets of Langerhans from different species suggest that actin polymerization might be a universal intracellular event accompanying cell surface receptor perturbation in eukaryotic cells.
Fibronectin fragment(s) are chemotactic for human peripheral blood monocytes.
Authors: Norris D A , Clark R A , Swigart L M , Huff J C , Weston W L , Howell S E
Published: December 2022

Both plasma-derived and cell-derived fibronectin are deposited at sites of inflammation and wound healing and are associated with migrating cell populations including monocytes/macrophages. We found that fibronectin fragments generated by endogenous protease(s) are potent chemoattractants for human peripheral blood monocytes, whereas intact fibronectin has no activity. Fibronectin preparations produced by gelatin affinity chromatography in the absence of protease inhibitors contained 90 to 220 kd fragments and had potent chemotactic and chemokinetic activity for monocytes but no activity for human neutrophils or lymphocytes. The addition of phenylmethylsulfonyl fluoride to plasma reduced but did not eliminate the recovery of fibronectin fragments and likewise reduced the chemotactic activity. When the preparations were further purified by DEAE ion exchange and Sepharose 4B molecular sieve chromatography, however, intact fibronectin was recovered that lacked both chemotactic and chemokinetic activity. When fragment-poor fibronectin was allowed to sit at 25 degrees C in NaN3 but without protease inhibitors, increased fragmentation and increased chemotactic activity were noted. In addition, chemotactically active small m.w. fragments arose from high m.w. fragments or from intact fibronectin as demonstrated by rechromatography experiments over Sephadex G-150. These findings suggest that proteolytic cleavage of fibronectin during inflammatory processes produces fragments that selectively augment the recruitment of monocytes into tissue sites of inflammation.
Isolation and characterization of a monoclonal antibody-resistant antigenic mutant of Toxoplasma gondii.
Authors: Kasper L H , Crabb J H , Pfefferkorn E R
Published: December 2022

Several monoclonal antibodies against Toxoplasma gondii were parasiticidal in the presence of normal human serum as measured by reduction in plaque titer or in assays that detected lysis. One monoclonal antibody, G, was used to select a resistant mutant from a large population of chemically mutagenized wild-type parasites. This mutant retained the wild-type sensitivity to other monoclonal antibodies and to polyclonal antisera. A comparison of surface radioiodinated wild-type and mutant parasites by using one and two-dimensional electrophoresis showed that the mutant lacked a protein (or proteins) of approximate m.w. 22,000. An immunoprecipitation procedure using monoclonal antibody G yielded a protein(s) of this m.w. from surface radioiodinated wild-type T. gondii but not from surface radioiodinated mutant parasites.
Variable and common antigens of Babesia bovis parasites differing in strain and virulence.
Authors: Kahl L P , Anders R F , Rodwell B J , Timms P , Mitchell G F
Published: December 2022

Virulent and avirulent K strain (KV and KA) and virulent L strain (LV) Babesia bovis parasites were biosynthetically labeled with 35S-methionine. Labeled proteins, extracted in detergent from infected cultures, were analyzed by two-dimensional gel electrophoresis. Protein antigens common to these forms of babesia and those specific for strain and correlating with the degree of virulence were identified by immunoprecipitation with antisera. Dominant labeled protein antigens were found to differ both between the K and L strains of B. bovis and between virulent (KV) and avirulent (KA) forms of the K strain. Partial cleavage of biosynthetically labeled proteins by staphylococcal V-8 protease and peptide mapping revealed that no extensive amino acid homology existed between the candidate variant antigens. KA B. bovis parasites are currently in use as a live attenuated vaccine for bovine babesiosis in Australia. Antigens that are better expressed in KA relative to virulent strains may therefore be markers of avirulence and/or candidate "host-protective antigens" of B. bovis. At least one protein (Mr 43,000) was identified as being a dominant labeled antigen of KA that is poorly represented in the KV and LV B. bovis isolates.
Limitation of VSV infection by the host's response to VSV-associated cellular antigens.
Authors: Hecht T T , Paul W E
Published: December 2022

It has been reported that during the maturation of enveloped viruses, host proteins such as H-2 antigens of the mouse associate with the budding viruses. This finding led us to investigate the possible biologic significance of this association. In our studies, we examined, with purified vesicular stomatitis virus (VSV) from various sources, the in vivo infection of mice immunized with allogeneic tumors. Immunization of H-2k mice with an H-2d tumor caused the limitation of replication, within the spleen, of VSV derived from an H-2d cell line compared with the replication of VSV derived from an H-2k line. Conversely, immunization of H-2d mice with an H-2k tumor caused the limitation of replication of VSV derived from an H-2k cell line. Viral mixture experiments ruled out indirect inactivation or inhibition of virus replication by nonspecific factors, such as immune interferon, as having a major role in the observed limitation of VSV replication. We conclude that virus infections can be limited by an immune response directed against the specific host surface antigen that the virus carries in its envelope.
Regulation of human natural killing. II. Protective effect of interferon on NK cells from suppression by PGE2.
Authors: Leung K H , Koren H S
Published: December 2022

Activation of human natural killer (NK) cells in vitro with interferon (IFN) and poly I:C results in a partial loss of sensitivity of these cells to suppression by PGE2. The acquired resistance to suppression can be induced with the large granular lymphocytes (LGL) in the absence of monocytes. With K562, HSB, and CEM used as NK target cells, the IFN-induced resistance to suppression by PGE2 is observed with all three target cells. Furthermore, ADCC activity of IFN-activated cells against tumor (SB-TNP) and erythroid (CRC-TNP) target cells is also less susceptible to suppression by PGE2. The dual effect of IFN on NK cells is prompt; the augmentation of NK activity and the acquired resistance to suppression by PGE2 can be seen after 3 hr of treatment with IFN. Both of these characteristics seem to be quite stable for at least 24 hr. Spleen cells from mice (CBA, C3H, and BALB/c nude) treated in vivo with poly I:C also acquire partial resistance to suppression by PGE2. Our data therefore suggest that IFN-stimulated NK cells are protected from suppression by PGE2. Biologically, the IFN-induced protective effect may be beneficial to host resistance to neoplasia.
Neutralization of native human gamma interferon (HuIFN gamma) by antibodies to a synthetic peptide encoded by the 5' end of HuIFN gamma cDNA.
Authors: Johnson H M , Langford M P , Lakhchaura B , Chan T S , Stanton G J
Published: December 2022

A synthetic peptide corresponding to the N-terminal amino acid sequence of human gamma-interferon (HuIFN gamma), based on the cDNA sequence, was used to produce antibodies in rabbits that were reactive with native HuIFN gamma. Antibodies from all immunized rabbits neutralized the antiviral activity of HuIFN gamma. Significant neutralization of other HuIFN and mouse IFN was not observed. The peptide had the sequence Cys-Tyr-Cys-Gln-Asp-Pro-Tyr-Val-Lys-Glu-Ala-Glu-Asn-Leu-Lys-Lys-Tyr-Phe-Asn-Ala ,and was coupled to keyhole limpet hemocyanin by disulfide linkage with the use of cystamine. The specificity of the antibodies produced to the peptide was compared to that of antibodies produced to native HuIFN gamma by neutralization of HuIFN gamma and by reactivity with peptide in the enzyme-linked immunosorbent assay (ELISA). The ratio of anti-peptide antibody neutralization of HuIFN gamma vs reactivity with peptide in the ELISA was at least 28-fold lower than for anti-HuIFN gamma antibody. Thus the antibodies to peptide and to HuIFN gamma were directed primarily against different determinants on native HuIFN gamma or the anti-HuIFN gamma antiserum probably contained antibodies to additional determinants. The anti-peptide antibodies should be useful for further characterization and purification of HuIFN gamma.
Lyt phenotype of H-2b CTL effectors and precursors specific for the SV40 transplantation rejection antigen.
Authors: Flyer D C , Anderson R W , Tevethia S S
Published: December 2022

The immune effector cells mediating the in vitro immune response to the SV40 transplantation rejection antigen were characterized by using monoclonal antibody directed against lymphocyte differentiation (Lyt) antigens. Two distinct T lymphocyte populations were found to be responsible for the in vitro lysis of SV40-transformed cells, and Lyt 1+,2+ cytotoxic T lymphocyte (CTL) that is present in the spleens of SV40 immunized mice 9 days postimmunization and an Lyt 1-,2+ CTL that is generated by secondary in vitro stimulation of in vivo primed spleen cells. During secondary in vitro stimulation of SV40 immune spleen cells obtained 9 days postimmunization, a shift in the Lyt phenotype of the CTL from Lyt 1+,2+ to Lyt 1-,2+ is observed. Although the Lyt 1-,2+ CTL can be derived from Lyt 1-,2+ noncytotoxic memory cells, it is not known whether the Lyt 1+,2+ CTL differentiates into an Lyt 1-,2+ CTL during in vitro stimulation.
An adherent cell lyses virus-infected targets: characterization, activation, and fine specificity of the cytotoxic cell.
Authors: Letvin N L , Kauffman R S , Finberg R
Published: December 2022

We have previously reported that mice with defective T lymphocyte function clear a primary reovirus type 1 infection in a normal fashion. The present studies were initiated to determine what cells may play a role in the clearance of this primary infection. We show that macrophages from unprimed mice are capable of lysing reovirus type 1-infected target cells in the absence of specific antibody. Macrophages from nu/nu mice have higher levels of this lytic activity than macrophages from nu/+ and normal mice. In addition, PEC from endotoxin nonresponsive C3H/HeJ mice have virtually no anti-viral lytic activity, while PEC from C3H/FeJ mice have high levels of such activity. Incubation of PEC from C3H/HeJ mice overnight in Con A supernatants restores this lytic activity. PEC are capable of lysing reovirus type 1-infected target cells but not those infected with type 3 reovirus. Using intertypic recombinant viruses, we show this striking target cell specificity to be a property of the sigma 1 protein, the viral hemagglutinin.
Production of prostaglandin E and an interleukin-1 like factor by cultured astrocytes and C6 glioma cells.
Authors: Fontana A , Kristensen F , Dubs R , Gemsa D , Weber E
Published: December 2022

When treated with lipopolysaccharide (LPS), cultured murine astrocytes released significant amounts of prostaglandin E, which caused an inhibition of the in vitro proliferative response of C3H/HeJ thymocytes to mitogen. In addition, an interleukin 1 (IL 1)-like factor secreted by LPS-treated glia cell cultures and by C6 glioma cells was detected. The characterization of the factor as an IL 1-like mediator is based on the findings that the factor 1) enhances the mitogen-induced thymocyte proliferation, 2) exhibits no interleukin 2 (IL 2) activity, but 3) augments IL 2 production by mitogen-stimulated thymocytes, and 4) has a m.w. between 13,500 and 18,000 when generated in serum-free conditions. These observations suggest that astrocytes may interact with the immune system by elaborating nonspecific factors that modulate lymphocyte proliferation. This property of astrocytes may be important in the generation of specific immune responses in the brain, which is considered to be an immunologically privileged organ as it is anatomically sequestered from the immune system.
Contrasting effects of lactoferrin on human lymphocyte and monocyte natural killer activity and antibody-dependent cell-mediated cytotoxicity.
Authors: Nishiya K , Horwitz D A
Published: December 2022

Iron and the iron-binding protein lactoferrin (LF) have significant effects on natural killer (NK) and antibody-dependent cellular cytotoxicity (ADCC). Human adherent and nonadherent blood mononuclear cells were incubated with K562 cells and antibody-sensitized Chang cells in short-term chromium-release assays. Ferric citrate (10(-3) M) inhibited both adherent and nonadherent NK cell activity, but had no effect upon ADCC. LF markedly affected adherent monocyte cytotoxicity, but had no effect on nonadherent lymphocytes. LF enhanced NK in a dose-dependent manner, but similar concentrations paradoxically inhibited ADCC. LF acted directly upon the adherent effector cell because pretreatment of cells for 30 min was sufficient for enhancement. Fe-saturated LF as well as the unsaturated protein enhanced adherent cell NK. Transferrin in all concentrations tested did not alter NK activity. These studies show inhibitory effects of iron on immune function in addition to those previously described and reveal a new regulatory role for LF. The selective effect of LF on adherent cells provides further evidence that monocytes, at least in the adherent state, can have potent NK activity. The opposite effects of LF on NK and ADCC are unexplained and may serve as a probe to define the mechanisms involved.
Hanganutziu-Deicher antibodies in infectious mononucleosis and other diseases.
Authors: Morito T , Kano K , Milgrom F
Published: December 2022

An enzyme immunoassay (EIA) was developed for the detection of heterophile, Hanganutziu-Deicher (H-D) antibodies in sera of patients with infectious mononucleosis (IM) and various other diseases. The EIA with a high m.w. glycoprotein (HMWGP) isolated from bovine erythrocyte stromata was shown to detect H-D antibodies directly, in spite of higher titers of Paul-Bunnell (P-B) antibodies in the IM sera. Absorption and inhibition studies of IM sera demonstrated H-D specificity of the antibodies combining with HMWGP in the EIA. The H-D antibodies were found in sera of 56% Caucasians and 27% of Japanese suffering from IM. The vast majority of the H-D antibodies in IM sera was of IgM class. Sera of patients with various other diseases also gave positive results: rheumatoid arthritis, 22%; syphilis, 19%; cancer of the gastrointestinal tract, 13%; and lepromatous leprosy 9.7%. The incidence of positive results in control sera from apparently healthy subjects was less than 4%. Results of this study confirmed our previous observation that whereas P-B antigens appear in immunogenic form in only IM, the H-D antigen is expressed as an immunogen in various diseases including IM.
Immune deficiency in the X-linked lymphoproliferative syndrome. II. Immunoregulatory T cell defects.
Authors: Lindsten T , Seeley J K , Ballow M , Sakamoto K , St Onge S , Yetz J , Aman P , Purtilo D T
Published: December 2022

Surface phenotypic markers and the function of lymphocytes in patients affected with the X-linked lymphoproliferative syndrome (XLP) were studied. This syndrome is characterized by a defective response to infection with Epstein Barr virus (EBV). Normal numbers of B and T cells were detected with anti-Ig and monoclonal OKT3 antisera, respectively. T cell subset values, however, were persistently altered: cells reacting with OKT8 were significantly elevated in five of nine patients, accompanied by a slight decrease in the percentage of OKT4-positive cells, leading to abnormally low OKT4 to OKT8 ratios. One patient had a high OKT4 to OKT8 ratio due to low number of OKT8-positive cells. Lymphocytes from patients showed normal proliferation after stimulation with T and B cell mitogens. In contrast, Ig synthesis by lymphocytes after stimulation with B cell mitogens was markedly deficient: low or undetectable levels of one or all classes of Ig were detected, whereas cell lines established from EBV-infected B lymphocytes from patients produced normal quantities of Ig. These studies imply immune regulatory impairments in the patient with XLP.
Biosynthesis and glycosylation of the invariant chain associated with HLA-DR antigens.
Authors: Machamer C E , Cresswell P
Published: December 2022

The biosynthesis and glycosylation of the invariant (I) chain associated with HLA-DR alpha-beta chain complexes has been examined in human B lymphoblastoid cell lines. Two-dimensional polyacrylamide gel electrophoresis of HLA-DR immune precipitates from extracts of metabolically labeled cells demonstrated a processes form of the I chain, called Ip, which consists of a series of spots beginning near the basic I chain spot and ending near the acidic alpha spots. Pulse/chase labeling yielded information on the kinetics of processing of the invariant chain, as well as the finding that the association of Ip with alpha-beta chain complexes appears to be transient. Neuraminidase treatment of immune precipitates confirmed that Ip was a form of the I chain containing up to eight sialic acid residues. Labeling in the presence of tunicamycin suggested the presence of both N-linked and O-linked oligosaccharide units on the invariant chain. This processing pattern does not appear to be an artifact of B cell lines; it was seen in peripheral blood lymphocytes, freshly purified monocytes, and in an interleukin 2-dependent continuous T cell line that expressed HLA-DR. In addition, there appears to be a free pool of the invariant chain and its processed form that is not found associated with DR alpha and beta chains.
Alloantisera detect HLA-A-B-C and non-HLA differentiation antigens on human thymocytes.
Authors: Mahoney R J , Gazit E , MacCarthy-Shanley K , Martin-Alosco S , Palomaki G E , Smith D E , Yunis E J
Published: December 2022

Human thymocytes (THY) were examined for the expression of HLA-A,B,C antigens on their cell surface by using tissue typing alloantisera in the microcytotoxicity assay. Approximately 80% of the total THY population demonstrated antibody-mediated, C-dependent lysis with several alloantisera for each HLA-A,B,C specificity. The HLA phenotype of THY was verified by HLA typing autologous peripheral blood lymphocytes (PBL) from the thymus donor. Thymus tissue and PBL were obtained from cardiac surgical patients ranging in age from 3 mo to 12 yr. The capacity of THY to absorb HLA alloantibody was also demonstrated. Cross-absorption studies performed on PBL and THY by using HLA typing sera produced two important findings: 1) HLA typing sera that are devoid of non-HLA THY-specific antibody can be used to HLA type THY and 2) selected non-HLA sera from multiparous women, and selected HLA typing sera absorbed with PRL or platelets can be used to detect THY differentiation antigens. Taken together, cytotoxicity data, absorption capacities, cross-absorption studies, and statistical analysis indicate that HLA-A,B,C alloantigens and non-HLA polymorphic differentiation antigens detected by alloantisera are co-expressed on the cell surface of the majority of human THY.
Augmentation of collagen arthritis by synthetic analogues of retinoic acid.
Authors: Trentham D E , Brinckerhoff C E
Published: December 2022

We evaluated the effect of administering orally two synthetic analogues of retinoic acid, 13-cis-retinoic acid and all-trans-N-(4-hydroxyphenyl)-retinamide to age-matched female Sprague-Dawley rats immunized with native chick type II collagen in incomplete Freund's adjuvant. Ingestion of a diet containing 13-cis-retinoic acid was associated with a significant increase in the severity of collagen arthritis, but there was no effect on weight gain or hemagglutinating antibody titers and delayed-type hypersensitivity to type II collagen. In two separate trials, ingestion of 4-hydroxyphenyl retinamide also significantly enhanced the severity of arthritis. Monolayer cultures of dissociated synovial cells taken from arthritic rats, but not nonarthritic rats, released prostaglandin E2 (PGE2) and collagenase into the medium. The level of PGE2 production was significantly decreased by in vivo or in vitro exposure to 4-hydroxyphenyl retinamide, whereas the addition of 13-cis-retinoic acid to the cultures had no effect on PGE2 release by the arthritic synovial cells. Five rats fed the 13-cis-retinoic acid-containing diet for 5 mo did not develop clinical or histologic evidence of arthritis. These data demonstrate that both retinoids possess potent enhancing properties for an experimentally inducible autoimmune arthritis, that synovial cells produce PGE2 and collagenase in this model, and that production of PGE2 can be suppressed by 4-hydroxyphenyl retinamide.
Celiac sprue: correlation with murine T cell responses to wheat gliadin components.
Authors: Kagnoff M F , Austin R K , Johnson H C , Bernardin J E , Dietler M D , Kasarda D D
Published: December 2022

Celiac sprue is a disease in humans that is characterized by small intestinal mucosal injury and malabsorption. Dietary exposure to gliadin and similar proteins in rye and barley activates the disease in susceptible individuals. Celiac sprue appears to be the only disease with a marked HLA-association in which the proteins that activate the disease currently are well known. However, bread wheat gliadins are a complex mixture of proteins that contain at least 40 different components. In the present study we have purified the major gliadin components of Scout 66 wheat and used these proteins to examine murine T cell proliferative responses to gliadin. Differences in T cell proliferation stimulated by alpha-, beta-, gamma-, and omega-gliadins paralleled the known structural differences among these proteins. After priming with whole gliadin, the components that stimulated T cell proliferation were the same as those recognized to activate celiac sprue in humans. Studies with reduced and alkylated A-gliadin (i.e., S-methyl A-gliadin) suggested that epitopes determined by the native conformation of A-gliadin may be important in its interaction with T cells. By using three different A-gliadin peptides that span the entire molecule, T cell proliferative responses were shown to be stimulated predominantly by antigenic determinants on the NH2-terminal peptide.
Biochemical signals transmitted by Fc gamma receptors: triggering mechanisms of the increased synthesis of adenosine-3',5'-cyclic monophosphate mediated by Fc gamma 2a- and Fc gamma 2b- -receptors of a murine macrophage-like cell line (P388D1).
Authors: Nitta T , Suzuki T
Published: December 2022

The specific binding of IgG2a or IgG2b subclass monoclonal anti-sheep erythrocyte antibodies to P388D1 cell surface Fc gamma 2aR3 or Fc gamma 2bR, respectively, triggered the synthesis of adenosine-3'5'-monophosphate (cAMP) to an approximately same extent by the mechanisms that are apparently unique for each type of Fc gamma Rs. Fc gamma 2aR appeared to trigger directly, upon binding of IgG2a antibodies, the adenylate cyclase system without requiring the participation of guanine nucleotide-binding (G/F) regulatory protein, because the Fc gamma 2aR-triggered cAMP synthesis, which reached maximum within 30 min, was not significantly affected by an uncoupler, Mn++ or by addition of guanosine triphosphate (GTP) analog, 5'-guanylylimidodiphosphate (Gpp(NH)p). In contrast, Fc gamma 2bR appeared to stimulate indirectly the G/F regulatory requiring-adenylate cyclase system by generating prostaglandins, since the cAMP synthesis, which required 90 min to reach plateau after binding of IgG2b to Fc gamma 2bR, was totally suppressed by phospholipase A2 inhibitor (p-bromophenacylbromide) or cyclo-oxygenase inhibitor (indomethacin), partially suppressed by Mn++, and slightly increased by Gpp(NH)p. Furthermore, the inhibition of phagocytic process by cytochalasin D increased cAMP synthesis mediated by Fc gamma 2aR (about 70% at 2 micrograms/ml), but did not affect Fc gamma 2bR-mediated cAMP synthesis. In addition, our data suggested that both Fc gamma 2aR- and Fc gamma 2bR-mediated cAMP synthesis are independent from beta-adrenergic receptor-mediated stimulation of the adenylate cyclase system, since either beta-agonist (isoproterenol) or beta-antagonist (propranolol) did not affect significantly the levels of cAMP produced in response to EA-stimulation.
The antigenic reactivity of small fragments derived from human myelin basic protein peptide 43-88.
Authors: Whitaker J N
Published: December 2022

In an effort to develop immunochemical reagents for detecting small peptides originating from myelin basic protein (BP), the antigenic determinants of fragments from human BP peptide 43-88 were examined. Antisera were produced in nine sheep and forty rabbits immunized with BP, BP peptide 43-88, or a region derived from within or containing a portion of BP peptide 43-88. These included custom synthesized peptides 51-67, 67-80, 74-84, 79-88, and 83-95. Reactivities were assessed by double antibody radioimmunoassay (DA-RIA) using radiolabeled BP or BP peptides. For peptides 74-84, 79-88, and 83-95 it was necessary to synthetically add a terminal tyrosine residue for radioiodination. Antisera to peptides 51-67, 67-80, 74-84, 79-88, and 83-95 showed much greater reactivity with the homologous antigen, with variable, but sometimes no, reactivity against BP or BP peptide 43-88. This was particularly evident in displacement DA-RIA. Of the small peptides, antisera to whole BP reacted best with peptide 83-95, whereas antisera to peptide 43-88 reacted best with peptide 79-88. Placement of the synthetically added tyrosine had a marked influence on the reactivity of BP peptide 79-88: antisera to BP peptide 43-88 reacted much better with radioiodinated tyrosinyl peptide 79-88 than with radioiodinated peptide 79-88-tyrosine. These results indicate that within a region of BP encompassing residues 51 through 95 a number of potential antigenic determinants exist. Some of the determinants on the small peptides represent distinctive conformational determinants or are inaccessible in BP peptide 43-88. The ability to detect small BP peptides by immunoassay necessitates that the identity of the peptide be known and that antibody reagents capable of reacting with the peptide(s) be available.
Inhibitory action of elevated levels of adenosine-3':5' cyclic monophosphate on phagocytosis: effects on macrophage-Trypanosoma cruzi interaction.
Authors: Wirth J J , Kierszenbaum F
Published: December 2022

The effects of agents that elevate intracellular levels of cyclic AMP on the in vitro interaction of mouse peritoneal macrophages with virulent bloodstream forms of a reticulotropic strain of Trypanosoma cruzi were investigated as a part of our efforts to define the requirements for tissue invasion by this intracellular human pathogen. At optimal, non-toxic concentrations, both L-isoproterenol and prostaglandin E1, agents that increase cyclic AMP levels by activating adenylate cyclase via different mechanisms, reduced the uptake by T. cruzi by the macrophages by approximately 30 and 70%, respectively, and also caused a reduction in the numbers of macrophages capable of incorporating the parasites. Similar results were obtained when either theophylline, which increases cyclic AMP levels by inhibiting the catabolic effect of phosphodiesterase activity, was incorporated into the cultures or by direct addition of dibutyryl cyclic AMP. Reductions produced with optimal concentrations of these drugs amounted to approximately 40 to 50%. The present results indicate that binding and uptake of virulent forms of a reticulotropic strain of T. cruzi by macrophages from a susceptible host are under the regulatory influence of cellular cyclic AMP levels.
Delivery of lethal hits by cytotoxic T lymphocytes in multicellular conjugates occurs sequentially but at random times.
Authors: Perelson A S , Bell G I
Published: December 2022

We propose a stochastic model to explain kinetic data on the delivery of lethal hits by cytotoxic T lymphocytes in multicellular conjugates. The comparison of our model with data of Zagury et al. suggests that cytotoxic T cells deliver lethal hits at random, and when conjugated to multiple target cels these cells attack undamaged target cells one at a time. The mean rate at which lethal hits are delivered per target cell is approximately the same for conjugates containing one or two target cells but slows substantially in conjugates containing three target cells. If our model is modified so that both previously hit and unhit target cells are susceptible to being lethally hit at the same rate, a very poor fit to Zagury et al's data is obtained. This leads us to conclude that previously hit cells are either not hit again or are hit at a substantially reduced rate.
The Bacteriophage-Antibacteriophage Reaction
Authors: Weiss Emil
Published: December 2022

Summary and Conclusions

Bacteriophage mixed with antibacteriophage serum and incubated twenty-four hours at 37°C. or longer shows the following properties: Filtered through the colloidal sac, it does not influence bacterial growth.It does not penetrate an average agar layer in a Petri dish, but it penetrates it where mixed with normal serum or alone.It is precipitated with 13.5 per cent sodium sulphate, but remains in the filtrate, when mixed with normal serum or alone.Bacteriophage is not destroyed by its union with the antibacteriophage serum.When a mixture of bacteriophage and antibacteriophage serum is digested with trypsin the bacteriophage appears again active.
Macrophage maturation: differences in complement secretion by marrow, monocyte, and tissue macrophages detected with an improved hemolytic plaque assay.
Authors: Alpert S E , Auerbach H S , Cole F S , Colten H R
Published: December 2022

In order to examine one function of mononuclear phagocytes during maturation from bone marrow precursors to tissue macrophages, an improved hemolytic plaque assay for the detection of synthesis of the second (C2) and fourth (C4) components of C by single cells was developed. With this method, production of C2 and C4 was assessed in cell populations derived from bone marrow, blood, lung, peritoneum, and spleen. The proportion of cells producing C2 and C4 in each population varied. Approximately 10% of bone marrow cells produced C4, but not detectable C2 plaque-forming cells (PFC) were detected. Circulating monocytes yielded about 10% PFC each for C2 and C4. The proportion of C2-producing cells in tissue macrophages varied from approximately 2% in bronchoalveolar macrophages to about 45% in peritoneal and splenic macrophage populations, whereas C4 production by macrophages from lung, peritoneum, and spleen were all approximately 45%. These data suggest that differences in C biosynthesis characterize mononuclear phagocytes at different stages of maturation.
Two different rheumatoid factor-producing cell populations distinguished by the mouse erythrocyte receptor and responsiveness to polyclonal B cell activators.
Authors: Fong S , Vaughan J H , Carson D A
Published: December 2022

The subsets of human peripheral blood B lymphocytes from which Epstein Barr virus- (EBV) and pokeweed mitogen- (PWM) induced IgM anti-IgG autoantibody-producing B cells arise have been compared. EBV-induced IgM anti-IgG autoantibodies preferentially derive from a subset of B cells that forms rosettes with mouse erythrocytes. In contrast, PWM-induced IgM anti-IgG antibodies preferentially arise from a B cell subset lacking the mouse erythrocyte receptor.
Human T cell hybridomas specific for Epstein Barr virus-infected B lymphocytes.
Authors: Lakow E , Tsoukas C D , Vaughan J H , Altman A , Carson D A
Published: December 2022

A mutant of the Jurkat human T lymphoblastoid cell line deficient in hypoxanthine phosphoribosyltransferase, and resistant to ouabain, was fused with peripheral blood T lymphocytes primed in vitro with Epstein Barr virus- (EBV) transformed autologous B lymphocytes. After selection of somatic cell hybrids and cloning, hybridoma cell lines were obtained that reacted with autologous EBV-infected B lymphocytes, as detected by the release of interleukin 2 into the culture medium. The hybridomas did not react with i) EBV-uninfected autologous or allogeneic B lymphocytes, ii) three out of four allogeneic EBV-transformed cell lines, or iii) two established EBV-negative B cell lines. These functional hybridomas may ultimately prove useful in dissecting the means by which human T lymphocytes recognize and regulate EBV infection in vivo.
Induction of human IgE synthesis by a factor derived from T cells of patients with hyper-IgE states.
Authors: Saryan J A , Leung D Y , Geha R S
Published: December 2022

The requirements for the induction of IgE synthesis in normal B cells were studied. In contrast to peripheral blood lymphocytes (PBL) from allergic subjects, normal PBL failed to synthesize IgE spontaneously in vitro. Pokeweed mitogen (PWM) and Epstein Barr virus (EBV) failed to induce IgE synthesis in normal PBL and in tonsil lymphocytes. In the case of PWM, this failure was not overcome by prior removal of T8+ cells, which were shown previously to contain IgE-specific suppressor cells. In the case of EBV, the failure to induce IgE synthesis was not overcome by prior removal of sheep rosette-forming cells. Supernatants of T cells derived from three groups of patients with elevated serum IgE (hyper-IgE syndrome, atopic dermatitis, and acute graft-vs-host disease) induced significant IgE synthesis in cultures of normal B cells without causing an increase in IgE synthesis. In contrast, supernatants of normal T cells failed to induce IgE synthesis. Release of the IgE isotype-specific helper factor was inhibited by cycloheximide and tunicamycin, and its activity was destroyed by treatment with trypsin and neuraminidase. These results indicate that whereas classical polyclonal B cell activators (PWM, EBV) fail to induce IgE synthesis by normal B cells, IgE synthesis is readily induced by an IgE-specific helper factor released by T cells from patients with hyper-IgE states.
Naturally abundant basophils in the snapping turtle, Chelydra serpentina, possess cytophilic surface antibody with reaginic function.
Authors: Mead K F , Borysenko M , Findlay S R
Published: December 2022

Basophils constitute 50 to 63% of the blood leukocytes in Chelydra serpentina, the snapping turtle. Immunoglobulin (Ig) on the surface of the turtle basophil was detected by indirect immunofluorescence by using an IgG fraction from rabbit anti-turtle Ig serum (RATIg) and a fluoresceinated goat anti-rabbit antibody incubated at 4 degrees C. However, when the cells were incubated with RATIg at 22 degrees C, the basophil number, as determined by Wright's stain and neutral red counts, decreased dramatically. This morphologic evidence of degranulation was directly proportional to the antiserum concentration. Degranulation also correlated with cell histamine release (r = 0.73). In other experiments, turtle basophils were found to express antigen-specific surface Ig after immunization with sheep red blood cells (SRBC). Washed basophils from immunized turtles formed basophil-SRBC rosettes in vitro. Basophils from control turtles did not. Basophil-SRBC rosettes could also be induced by in vitro passive sensitization by preincubation of normal turtle basophils in the SRBC immune turtle sera. This study shows clearly that the turtle basophil has an immune capacity analogous to the mammalian basophil/mast cell. This study also contains the first direct evidence for the existence of reaginic antibody (or antibodies) in an ectothermic vertebrate. Finally, C. serpentina is proposed as a unique animal model for the study of basophil function.
Antigenic determinants of vesicular stomatitis virus: analysis with antigenic variants.
Authors: Lefrancois L , Lyles D S
Published: December 2022

Antigenic variants of vesicular stomatitis virus (VSV) serotypes New Jersey and Indiana (VSV-NJ, VSV-Ind) were selected by using a panel of monoclonal antibodies (MAb) specific for the major surface glycoprotein (G-protein). The reactivity of antigenic variants with the panel of MAb confirmed observations made by competitive binding assays that four distinct antigenic sites (A-D)NJ on the VSV-NJ G-protein and four partially overlapping sites (A, B1, B2, C)Ind on the VSV-Ind G-protein are involved in virus neutralization. Furthermore, subregions within the A epitopes of both serotypes were detected by variant analysis. The frequency of variation at most epitopes was 1 in 10(5) for VSV-NJ and 1 in 10(6) for VSV-Ind. The A3 and C determinants of VSV-Ind, however, defined by MAb that exhibited overlap in binding to other epitopes, appeared to be relatively invariant. Multiple mutations may be necessary to abolish antibody binding at these sites. Overlap of the C group of anti-VSV-Ind MAb with the A epitopes was assigned to the A2 subregion, because variants selected with A2 MAb show reduced binding of C MAb. Heterogeneous antisera from a primary immune response could detect differences in reactivity between variants at the A epitopes and wild-type VSV-NJ or VSV-Ind, suggesting the A epitope is immunodominant. Hyperimmune sera could detect a small difference between ANJ and BNJ variants compared to wild-type VSV-NJ, but could not distinguish between VSV-Ind variants and wild-type VSV-Ind.
Qualitative differences between dimeric and trimeric stimulation of human basophils.
Authors: MacGlashan D W , Schleimer R P , Lichtenstein L M
Published: December 2022

Previous studies from this laboratory demonstrated differences between antigenic and anti-IgE antibody stimulation of human basophils under the pharmacologic control of indomethacin. We show here that this difference may be due to the type of aggregation these stimuli induce on the cell surface. We found that the synthetically cross-linked trimer of IgE caused histamine release that was enhanced by indomethacin, whereas dimeric IgE induced-release was not. This result was not due to a difference in the kinetics of release by these two stimuli. These results suggest that the state of aggregation of Fc receptors differentially affects various cellular enzyme systems.
Modulation of granulomatous hypersensitivity. V. Participation of histamine receptor positive and negative lymphocytes in the granulomatous response of Schistosoma mansoni-infected mice.
Authors: Weinstock J V , Chensue S W , Boros D L
Published: December 2022

The possible role of histamine and histamine-receptored inflammatory cells in the granulomatous response of Schistosoma mansoni-infected mice was examined. Special staining revealed the presence of numerous mast cells, many partially degranulated within the liver granulomas. Treatment of infected mice with cimetidine (an H2 receptor antagonist) enhanced, and diphenyhydramine (an H1 receptor antagonist) decreased the granulomatous response. Fluorescein-labeled histamine-rabbit serum albumin conjugate (H-FRSA) and unlabeled conjugate (H-RSA)-coated culture plates were used to identify and isolate cells with histamine receptors. A large proportion of granuloma macrophages, lymphocytes, eosinophils, neutrophils, and splenic lymphocytes had histamine receptors. Elution of adherent cells from H-RSA-coated culture plates with H1 or H2 receptor antagonists suggested that receptors on granuloma cells were predominately H1 with some granuloma lymphocytes bearing H2-type receptors. Splenic lymphocytes from infected mice were functionally divided according to the presence or absence of histamine receptors on their cell surface. Receptor-negative lymphocytes appeared to mediate SEA-stimulated MIF production (TDH cells) and participated in the adoptive transfer of suppression of granulomas (TH cells). Whereas, TS cells appeared to have histamine receptors. Based on these data, it is inferred that lymphocytes that regulate lymphokine production (TS cells) within the granuloma may be triggered via their histamine receptors to exert suppressive activity.
Growth and characterization of T cell colonies from human thymus.
Authors: Lederman H M , Lee J W , Price G B , Gelfand E W
Published: December 2022

A semisolid microculture system was used to study T cell colonies grown from human thymocytes. Colony growth was absolutely dependent upon media conditioned by peripheral blood leukocytes (PBL) in the presence of phytohemagglutinin. Plating efficiency was further enhanced by the addition of a non-T, adherent, radiation-resistant (7500 rad) PBL subpopulation, but was not enhanced by culture supernatants of these cells. The T colony precursor cell in the thymus occurred with a frequency of 8.0 X 10(-3) and had a surface receptor for the OKT3 monoclonal antibody. Thymocyte colony cells were functionally distinct from PBL and the major thymocyte population. The colony cells proliferated in response to T cell mitogens, but only in the presence of exogenous growth factors. The cells stimulated normal PBL in mixed leukocyte culture (MLC), but did not respond to alloantigens in MLC or in assays of spontaneous cytotoxicity. This culture system should prove helpful in the study of human thymocyte differentiation.
Characterization of a "heteroclitic" cytotoxic lymphocyte clone: heterogeneity of receptors or signals?
Authors: Russell J H , Dobos C B
Published: December 2022

In this work we report the isolation of a cloned CTL that recognizes three genetically distinct specificities. Of interest is the fact that the hierarchy of the strength of these specificities is dependent on the functional assay used for their detection. This suggests that either the specificities are the result of interactions with independent receptors or the cell can modulate signals from cross-reactive antigens into different functional responses.
Activation of antigen-enriched b cells. I. Purification and response to thymus-independent antigens.
Authors: Snow E C , Vitetta E S , Uhr J W
Published: December 2022

The development of a procedure for the selection of a large number of functional antigen-binding B cells is described. Forty to 70% of the cells in the enriched population bind antigen, and the antigen-binding can be inhibited by pretreatment with either the free hapten (TNP-Lys) or anti-immunoglobulin. The enriched cells express both slgM and slgD and respond to mitogenic stimuli by proliferating and developing into antibody-forming cells. In contrast to normal spleen cells, however, the enriched cells also proliferate in response to submitogenic levels of TNP-Brucella abortus and TNP-LPS.