scholarly journals Ia Antigens and Fc Receptors of Mouse Peritoneal Macrophages as Determinants of Susceptibility to Lactic Dehydrogenase Virus

1985 ◽  
Vol 66 (7) ◽  
pp. 1469-1477 ◽  
Author(s):  
T. Inada ◽  
C. A. Mims
1980 ◽  
Vol 152 (5) ◽  
pp. 1248-1261 ◽  
Author(s):  
R M Steinman ◽  
N Nogueira ◽  
M D Witmer ◽  
J D Tydings ◽  
I S Mellman

Soluble products from antigen stimulated Trypanosoma cruzi-immune spleen cells enhanced the expression of Ia antigens on proteose-peptone-elicited mouse peritoneal macrophages (M phi). Acquisition of Ia paralleled M phi activation, previously shown to be mediated by this same source of lymphokine (LK). Expression of Ia and four other plasma membrane antigens was monitored by quantitative binding and radioautographic studies with 125I-monoclonal antibodies. Immune LK selectively enhanced expression of Ia and, to a lesser extent, H-2D relative to control LK from antigen-stimulated noninfected spleen. The levels of three other non-major histocompatibility complex (MHC) antigens, including the trypsin-resistant Fc receptor, were similar in cells exposed to both sources of LK. As little as 1% immune LK induced one-half maximal expression of Ia. Kinetic studies revealed that much of the Ia on freshly explanted peritoneal M phi was lost during the 1st d of culture. In the continued presence of immune LK, Ia was re-expressed on virtually all M phi by the 2nd and 3rd d. Alternatively, > 95% Ia negative populations were obtained by culturing the cells 3 d; then, addition of LK induced Ia on most cells within 1 d. Once induced, Ia persisted on the M phi surface for at least 2 d. [35S]methionine radiolabeling indicated that immune LK selectively increased radiolabeling of M phi Ia, again with other non-MHC-linked plasma membrane polypeptides as controls. LK-induced Ia-bearing M phi were tested as primary mixed leukocyte reaction stimulators. 1 x 10(5)-2 x 10(5) M phi did not stimulate 4.5 x 10(6) responding T cells, whereas 10(4) dendritic cells induced strong responses, as previously described. Because Ia-positive M phi do not actively sensitize T cells in a model immune response, we propose that M phi MHC products serve primarily as recognition sites for previously sensitized T cells, thereby enhancing T cell-mediated M phi activation.


1979 ◽  
Vol 150 (3) ◽  
pp. 607-621 ◽  
Author(s):  
J Michl ◽  
M M Pieczonka ◽  
J C Unkeless ◽  
S C Silverstein

We have examined the Fc- and complement-receptor function of resident and thioglycollate-elicited mouse peritoneal macrophages plated on surfaces coated with rabbit antibody-antigen complexes and with complement. We derive four major conclusions from these studies. (a) The trypsin-resistant Fc receptors of resident and thioglycollate-elicited macrophages are completely modulated when these cells are plated on rabbit antibody-antigen complexes. Residual Fc receptor activity is a result of the incomplete modulation of trypsin-sensitive IgG2a receptors. (b) The complement receptors of thioglycollate-elicited macrophages, but not of resident macrophages, are modulated when these cells are plated on complement-coated surfaces. The capacity of the two cell types to modulate their complement receptors is correlated with their ability to ingest complement-coated erythrocytes. (c) The complement and Fc receptors of both types of macrophages move independently of one another. (d) Complement masks the Fc segments of IgG in immune complexes thereby rendering them ineffective as ligands for macrophage Fc receptors.


1980 ◽  
Vol 152 (5) ◽  
pp. 1147-1161 ◽  
Author(s):  
BC Lane ◽  
J Kan-Mitchell ◽  
MS Mitchell ◽  
SM Cooper

Membrane proteins which selectively bind to the Fc portion of IgG were identified in the Nonidet P-40 extracts of radiolabeled thioglycollate- elicited mouse peritoneal macrophages. Affinity columns of various IgG preparations coupled to Sepharose 4B were used to absorb the Fc-binding proteins. Analysis of the acetic acid or sodium dodecyl sulfate (SDS) eluates from aggregated human IgG or antigen-complexed rabbit IgG columns revealed two Fc(gamma)/-specific proteins with apparent 67,000 and 52,000 mol wt. These proteins were not detected in acid or SDS eluates from F(ab')(2) columns or in eluates from IgG column, over which were passed lysates of Fc receptor-negative cells. With the use of affinity columns that contained aggregated mouse myeloma proteins of different IgG subclasses, we found that the 67,000-dahon protein selectively binds to IgG2a, whereas the 52,000-dalton protein binds to IgG1 and IgG2b. Neither protein was found in SDS eluates from IgG3 columns. Trypsin treatment of the macrophages before detergent lysis removed the 67,000-dalton protein, although it leaves intact the 52,000-dalton protein. These results provide structural confirmation for the existence of separate Fc receptors on mouse macrophages and indicate that the two Fc-binding proteins identified in this study represent all or part of the trypsin- sensitive Fc receptor which binds IgG2a and the trypsin-resistant Fc receptor which binds IgG2b and IgG1.


1978 ◽  
Vol 148 (4) ◽  
pp. 903-914 ◽  
Author(s):  
J L van Snick ◽  
P L Masson

Complement was found to stimulate markedly the ingestion of soluble antigen-antibody complexes by mouse peritoneal macrophages. This was shown indirectly by measuring the release of degradation products when the complexes were labeled with 125I, or directly when the antigen, that was human transferrin, was labeled with 59Fe. In this case, the metal which was released from human transferrin inside the cells was not excreted, and its accumulation in the macrophages was a direct index of the uptake of immune complexes. The decay of radioactivity in macrophages after ingestion of 125I-labeled complexes was similar when they were taken up with or without complement, indicating that complement acts primarily on ingestion and not on digestion or excretion. The ingestion of complexes was morphologically confirmed using fluorescein-labeled antigen in the immune complexes. The opsonic effect of complement was also observed with IgM aggregates indicating that soluble complexes can be ingested through complement receptors without involvement of Fc-receptors, as required for particulate antigen-antibody complexes.


1988 ◽  
Vol 106 (3) ◽  
pp. 657-666 ◽  
Author(s):  
F Di Virgilio ◽  
B C Meyer ◽  
S Greenberg ◽  
S C Silverstein

Cytosolic free Ca2+ ([Ca2+]i) homeostasis was investigated in mouse peritoneal macrophages and in the macrophage-like cell line J774. [Ca2+]i measurements were performed in both cells in suspension and cells in monolayers loaded with either quin2 or fura-2. Resting [Ca2+]i was 110-140 and 85-120 nM for cell suspensions and monolayers, respectively. There were no significant differences in [Ca2+]i between the two macrophage populations whether quin2 or fura-2 were used as Ca2+ indicators. Addition of heat-aggregated IgG, IgG-coated erythrocyte ghosts, or a rat monoclonal antibody (2.4G2) directed against mouse Fc receptor II induced a rise in [Ca2+]i. This [Ca2+]i increase was consistently observed in J774 and peritoneal macrophage suspensions and in J774 macrophage monolayers; in contrast it was observed inconsistently in peritoneal macrophages in monolayer cultures. The increase in [Ca2+]i induced by ligation of Fc receptors was inhibited totally in macrophages in suspension and by 80% in macrophages in monolayers by a short preincubation of macrophages with PMA; however, phagocytosis itself was unaffected. The effect of reducing cytosolic Ca2+ to very low concentrations on Fc receptor-mediated phagocytosis was also investigated. By incubating macrophages with high concentrations of quin2/AM in the absence of extracellular Ca2+, or by loading EGTA into the cytoplasm, the [Ca2+]i was buffered and clamped to 1-10 nM. Despite this, the phagocytosis of IgG-coated erythrocytes proceeded normally. These observations confirm the report of Young et al. (Young, J. D., S. S. Ko, and Z. A. Cohn. 1984. Proc. Natl. Acad. Sci. USA. 81:5430-5434) that ligation of Fc receptors causes Ca2+ mobilization in macrophages. However, these results confirm and extend the findings of McNeil et al. (McNeil, P. L., J. A. Swanson, S. D. Wright, S. C. Silverstein, and D. L. Taylor. 1986. J. Cell Biol. 102:1586-1592) that a rise in [Ca2+]i is not required for Fc receptor-mediated phagocytosis; and they provide direct evidence that Fc receptor-mediated phagocytosis occurs normally even at exceedingly low [Ca2+]i.


1979 ◽  
Vol 9 (12) ◽  
pp. 979-984 ◽  
Author(s):  
Andrei Sulica ◽  
Maria Gherman ◽  
Cornel Medesan ◽  
John Sjöquist ◽  
Victor Gheţie

1983 ◽  
Vol 96 (3) ◽  
pp. 887-895 ◽  
Author(s):  
I S Mellman ◽  
H Plutner ◽  
R M Steinman ◽  
J C Unkeless ◽  
Z A Cohn

Macrophage receptors for the Fc domain of immunoglobulin G (IgG) can mediate the efficient binding and phagocytosis of IgG-coated particles. After internalization, phagocytic vacuoles fuse with lysosomes, initiating the degradation of their contents. Using specific monoclonal and polyclonal antireceptor antibodies, we have now analyzed the internalization and fate of Fc receptors during the uptake of IgG-coated erythrocytes and erythrocyte ghosts by mouse peritoneal macrophages. Receptor-mediated phagocytosis led to the selective and largely irreversible removal of Fc receptors (greater than 50%) from the macrophage plasma membrane. The expression of several other plasma membrane proteins (including a receptor for complement), recognized by a series of antimacrophage monoclonal antibodies, was affected only slightly. Interiorized Fc receptors were rapidly and selectively degraded. This was demonstrated by a series of turnover studies in which Fc receptor was immunoprecipitated from lysates of 125I-labeled macrophages. These experiments were made possible by the development of a polyclonal rabbit antiserum, raised against isolated Fc receptor, which recognized the receptor even in the presence of bound ligand. In control cells, the receptor turned over with a t1/2 of approximately 10 h; after phagocytosis, greater than 50% of the receptors were degraded with a t1/2 of less than 2 h. The turnover of other unrelated plasma membrane proteins was unaffected (t1/2 of 18-23 h) under these conditions.


Sign in / Sign up

Export Citation Format

Share Document