Regulation of Fc fragment-induced murine spleen cell proliferation.Morgan, E L; Weigle, W O
doi: 10.1084/jem.151.1.1pmid: 6965303
Murine splenic lymphocytes proliferate in response to supernatant material derived from Fc fragment-pulsed splenic adherent cells. The stimulatory supernatant results from the interaction of Fc fragments with adherent cells or adherent cell supernate. Isolation of the stimulatory material in the supernate by Sephadex chromatography revealed that the mitogenic component was a cleavage product of Fc with a mol wt of approximately 14,000. The spleen cell type responsible for the generation of mitogenic Fc subfragments appears to be a macrophage. Unstimulated macrophages release an active supernate without being exposed to Fc fragments. The supernate of unstimulated macrophages apparently contain an enzyme which is capable of cleaving Fc fragments into the 14,000-mol wt mitogenic molecules. The spleen cell population induced to proliferate in response to the adherent cell supernate is present in T-cell depleted and Sephadex G-10 filtered cell preparations. Depletion of cells bearing immunoglobulin on their surfaces results in a reduced proliferative response to the mitogenic supernatant material indicating that it is probably a B cell.
Mutual recognition of parental and F1 lymphocytes. Selective abrogation of cytotoxic potential of F1 lymphocytes by parental lymphocytes.Shearer, G M; Polisson, R P
doi: 10.1084/jem.151.1.20pmid: 6153111
Four different combinations of F1 hybrid mice (C57BL/10 X B10.A)F1, (C57BL/10 X B10.BR)F1, B6D2F1, and AKD2F1 were injected intravenously with spleen cells from parental strains. The T-cell-mediated cytotoxic potential of spleen cells from the injected F1 mice was assessed from 4 to 21 d later by in vitro sensitization with trinitrophenyl-modified parental or syngeneic F1 spleen cells (TNP-self) or with allogeneic spleen cells. The cytotoxic potential of the F1 mice to TNP-self as well as to alloantigens was abolished or severely depressed throughout this period when the respective H-2k,a,d parental spleen cells were injected. In contrast, the cytotoxic potential was unaffected or only marginally reduced when H-2b parental cells were injected. The induction of depressed cytotoxic activity was shown to be a result of a population of parental radiosensitive T lymphocytes. The results should be discussed with respect to (a) the genetic and mechanistic parameters associated with the differential depressive effects of parental cells expressing H-2b vs. H-2k,a,d antigens, and (b) the use of this system for investigating allogeneic receptors on T-lymphocyte populations.
Loss of Fc receptor activity after culture of human monocytes on surface-bound immune complexes. Mediation by cyclic nucleotides.Ragsdale, C G; Arend, W P
doi: 10.1084/jem.151.1.32pmid: 7350248
Human monocytes cultured on surface-bound immune complexes exhibited a loss of ability to form rosettes with IgG-sensitized sheep erythrocytes (EA). This loss was not a result of inhibition of Fc receptors by solubilized complexes nor of release of soluble factors by the cells. Loss of EA rosetting was not prevented by culture of monocytes at 4 degrees C, or by treatment with colchicine, cytochalasin B, or local anethetic agents. These results suggested that the loss was not secondary to capping or interiorization of Fc receptors. The results of other studies indicated that the Fc receptors were not damaged by lysosomal enzymes or oxygen radicals. Maintenance of EA rosetting ability of monocytes cultured on surface-bound immune complexes was seen after a 3-h preincubation of the cells in 100 mM 2-deoxy-D-glucose (2dG). A similar preincubation in ATP or in 8-bromoadenosine 3':5'-cyclic monophosphoric acid plus the phosphodiesterase inhibitor methyl isobutyl xanthine led to a partial loss of EA rosetting of cells on plain fibrin and to a partial reversal of the effects of 2dG seen with cells on complexes. We conclude that EA rosetting of monocytes cultured on surface-bound immune complexes is reduced by cyclic nucleotide-mediated effects on Fc receptor number or function.
Incidence and specificities of IgA and IgM anti-AgG autoantibodies in various mouse strains and colonies.van Snick, J L; Masson, P L
doi: 10.1084/jem.151.1.45pmid: 7350249
Mice, greater than 20 wk old, were tested for the presence of anti-IgG autoantibodies by agglutination and radioimmunoassay. IgA and IgM anti-IgG were found in the 129/Sv, C57BL/6, and DBA/2 strains from the local colony at the International Institute of Cellular and Molecular Pathology (ICP), at the Institut Pasteur de Paris (IP), and in the endotoxin-resistant C3H/He strain of ICP. These strains were negative at Iffa Credo (IC), and at The Jackson Laboratory (JL). Among 33 strains from the latter colony, 129/J, AKR/J, CBA/J, C57L/J, and NZB/BinJ were positive. All were specific pathogen-free and, excepting the NZB/BinJ, are not known to develop systemic autoimmune disorders. These differences between colonies suggest an influence of the environment on the production of anti-IgG. Evidence for the role of an infectious agent was provided by the fact that germ-free DBA/2 were negative in contrast to their SPF relatives. Strains which were positive at ICP and IP for anti-IgG had four-times higher serum levels of total IgA and two-times higher levels of total IgG than the corresponding negative strains from IC and JL. The anti-IgG titers differed markedly from one strain to the other in the same environment; e.g., in mice from ICP, BALB/c mice produced 40-times less anti-IgG than 129/Sv. IgA anti-IgG occurred only in high producers of anti-IgG. In these animals, the proportion of IgA vs. IgM anti-IgG was very different from one group to the other; C57BL/6 had mainly IgM anti-IgG, DBA/2 mainly IgA anti-IgG, and 129/Sv both IgM and IgA anti-IgG. The IgA anti-IgG from 129/Sv, 129/J, NZB/BinJ, C57L/J, DBA/2, and C3H/He had restricted hetero-, iso-, and allotypic specificities. It reacted only with mouse IgGa2, but not with the Ig-1b allotype. C57BL/6 also had IgA anti-IgG with a narrow specificity, but directed against IgG1 without allotypic restriction. In contrast to the specificity of IgA anti-IgG, the antibody activity of IgM anti-IgG was much broader, except in the 129/Sv and 129/J strains where IgM anti-IgG shared the same narrow specificity with IgA.
Biochemical and immunological characterization of the extracellular nucleases of group B streptococci.Ferrieri, P; Gray, E D; Wannamaker, L W
doi: 10.1084/jem.151.1.56pmid: 6985648
Nearly all group B streptococcal strains representing the five major serotypes were found to produce extracellular nucleases by screening with an agar-well-diffusion technique in DNA-methyl green agar plates. Three different nucleases have been isolated and partially purified by DEAE-and carboxymethyl-cellulose chromatography. They possessed different mobilities on polyacrylamide gel electrophoresis and different molecular weights. These nucleases, designated I, II, and III, are optimally activated by cations of calcium and manganese and exhibited RNase as well as DNase activity. Despite differences in their physical and biochemical properties, nucleases II and III appear antigenically similar, but distinct from nuclease I. These group B streptococcal nucleases are immunologically different from the nucleases of group A streptococci. Neutralizing activity, probably antibody, to nucleases II and III was found in human sera, and was most prevalent in sera of pregnant women colonized with group B streptococci and in their newborn infants.
T-cell-mediated suppression of anti-tumor immunity. An explanation for progressive growth of an immunogenic tumor.Berendt, M J; North, R J
doi: 10.1084/jem.151.1.69pmid: 6444236
The results of this paper are consistent with the hypothesis that progressive growth of the Meth A fibrosarcoma evokes the generation of a T-cell-mediated mechanism of immunosuppression that prevents this highly immunogenic tumor from being rejected by its immunocompetent host. It was shown that it is possible to cause the regression of large, established Meth A tumors by intravenous infusion of tumor-sensitized T cells from immune donors, but only if the tumors are growing in T-cell-deficient recipients. It was also shown that the adoptive T-cell-mediated regression of tumors in such recipients can be prevented by prior infusion of splenic T cells from T-cell-intact, tumor-bearing donors. The results leave little doubt that the presence of suppressor T cells in T-cell-intact, tumor-bearing mice is responsible for the loss of an earlier generated state of concomitant immunity, and for the inability of intravenously infused, sensitized T cells to cause tumor regression. Because the presence of suppressor T cells generated in response to the Meth A did not suppress the capacity of Meth A-bearing mice to generate and express immunity against a tumor allograft, it is obvious that they were not in a state of generalized immunosuppression.
Induction of acute cholecystitis by activation of factor XII.Becker, C G; Dubin, T; Glenn, F
doi: 10.1084/jem.151.1.81pmid: 6765972
Acute, acalculous cholecystitis is seen among patients suffering with bacterial sepsis, burns, trauma, or cancer; clinical conditions that could lead to activation of factor XII-dependent pathways and result in inflammation of the gall bladder. To test this hypothesis, dogs were injected intravenously with ellagic acid or rutin, known polyphenol activators of factor XII, or with Escherichia coli endotoxin, also known to activate factor XII, and monkeys were injected intravenously with ellagic acid. In both species, in vivo activation of factor XII-dependent pathways with polyphenol activator resulted in rapid and selective development of acute vasculitis in the serosa and muscularis of the gallbladder and margination of polymorphonuclear neutrophils in pulmonary blood vessels. Intravenous injection of E. coli endotoxin in dogs resulted in necrosis and thrombosis of vessels that were especially severe in the serosa and muscularis of the gallbladder but also present in vessels of many other organs. These observations indicate that blood vessels of the gall bladder and, to a lesser degree, the lung are especially sensitive to injury consequent to in vivo activation of factor XII-dependent pathways and, in view of the common ingestion of plant polyphenols, may provide important insight into the pathogenesis of cholecystitis in man.
Peripheral blood Ia-positive T cells. Increases in certain diseases and after immunization.Yu, D T; Winchester, R J; Fu, S M; Gibofsky, A; Ko, H S; Kunkel, H G
doi: 10.1084/jem.151.1.91pmid: 6985649
The Ia antigens, usually expressed primarily on B lymphocytes, are found on a small percentage of normal peripheral blood T cells (average 2.6% by fluorescence and 10.8% by rosette assay). Elevated levels up to 40% by both assays were observed in a high proportion of patients with rheumatoid arthritis. Increases also were found in patients with systemic lupus erythematosus and various types of infections. The increases were evident with a specific heteroantiserum, a hybridoma reagent, and DR specific alloantisera. Normal levels were present in multiple sclerosis and an assortment of metabolic and other disorders. A rise in similarly positive T cells occurred in normal individuals after immunization with tetanus toxoid or PPD. The cells primarily involved in all of these instances were small lymphocytes, which stained relatively weakly with the fluorescent reagents and were readily distinguishable from T-cell blasts. They were found to be enriched in isolated T gamma fractions but were also found in other T cells. The accumulated evidence indicated that these cells represent an expansion of one or more subsets of T cells found in normal individuals, and that their level in the peripheral blood may serve as an index of immunological stimulation.
Increased production of superoxide anion by macrophages exposed in vitro to muramyl dipeptide or lipopolysaccharide.Pabst, M J; Johnston, R B
doi: 10.1084/jem.151.1.101pmid: 7350246
After in vitro exposure to lipopolysaccharide (LPS) or muramyl dipeptide (MDP), cultured resident mouse peritoneal macrophages were primed to display enhanced generation of superoxide anion (O2-) in response to stimulation by phorbol myristate acetate (PMA) or opsonized zymosan. Priming with LPS (1 microgram/ml) produced a sevenfold enhancement of PMA-stimulated O2- generation; priming was detected within 30 min and persisted for at least 4 d. Exposure to MDP (1 muM) primed the macrophages to double their O2- release; the response was first observed after 4 h and persisted for at least 3 d. The priming response was not observed with stereoisomers of MDP, which are inactive as adjuvants. LPS and MDP appeared to work directly on the macrophages rather than indirectly by interacting with adherent lymphocytes: (a) Addition of nonadherent cell populations that contained lymphocytes had no effect on the response. (b) The response was normal with cells from nude mice, which lack mature T lymphocytes. (c) Macrophages from C3H/HeJ mice, whose B lymphocytes fail to respond to LPS, were weak in their response to priming LPS; the addition of normal (C3Heb/FeJ) nonadherent cells had no effect on this weak response. (d) The macrophage-like cell line J774.1 also showed enhanced O2--generating capacity after a 4-h exposure to LPS or MDP. The O2--generating capacity of macrophages primed with LPS in vitro was equivalent to that previously observed with cells elicited in vivo by injection of LPS or activated by infection with Bacille Calmette-Guérin. The data suggest that previous exposure to bacterial products could prime macrophages to respond with increased production of toxic oxygen metabolites on contact with invading microorganisms or tumor cells.