Macrophage Disappearance Reaction Research Articles

Selective oxidative protection leads to tissue topological changes orchestrated by macrophage during ulcerative colitis

Ulcerative colitis is a chronic inflammatory bowel disorder with cellular heterogeneity. To understand the composition and spatial changes of the ulcerative colitis ecosystem, here we use imaging mass cytometry and single-cell RNA sequencing to depict the single-cell landscape of the human colon ecosystem. We find tissue topological changes featured with macrophage disappearance reaction in the ulcerative colitis region, occurring only for tissue-resident macrophages. Reactive oxygen species levels are higher in the ulcerative colitis region, but reactive oxygen species scavenging enzyme SOD2 is barely detected in resident macrophages, resulting in distinct reactive oxygen species vulnerability for inflammatory macrophages and resident macrophages. Inflammatory macrophages replace resident macrophages and cause a spatial shift of TNF production during ulcerative colitis via a cytokine production network formed with T and B cells. Our study suggests components of a mechanism for the observed macrophage disappearance reaction of resident macrophages, providing mechanistic hints for macrophage disappearance reaction in other inflammation or infection situations.

Gut microbiota involved in leptospiral infections.

Leptospirosis is a re-emerging zoonotic disease worldwide. Intestinal bleeding is a common but neglected symptom in severe leptospirosis. The regulatory mechanism of the gut microbiota on leptospirosis is still unclear. In this study, we found that Leptospira interrogans infection changed the composition of the gut microbiota in mice. Weight loss and an increased leptospiral load in organs were observed in the gut microbiota-depleted mice compared with those in the control mice. Moreover, fecal microbiota transplantation (FMT) to the microbiota-depleted mice reversed these effects. The phagocytosis response and inflammatory response in bone marrow-derived macrophages and thioglycolate-induced peritoneal macrophages were diminished in the microbiota-depleted mice after infection. However, the phagocytosis response and inflammatory response in resident peritoneal macrophage were not affected in the microbiota-depleted mice after infection. The diminished macrophage disappearance reaction (bacterial entry into the peritoneum acutely induced macrophage adherence to form local clots and out of the fluid phase) led to an increased leptospiral load in the peritoneal cavity in the microbiota-depleted mice. In addition, the impaired capacity of macrophages to clear leptospires increased leptospiral dissemination in Leptospira-infected microbiota-depleted mice. Our study identified the microbiota as an endogenous defense against L. interrogans infection. Modulating the structure and function of the gut microbiota may provide new individualized preventative strategies for the control of leptospirosis and related spirochetal infections.

Monocytic Ontogeny of Regenerated Macrophages Characterizes the Mesotheliomagenic Responses to Carbon Nanotubes.

Macrophages are not only derived from circulating blood monocytes or embryonic precursors but also expand by proliferation. The origin determines macrophage fate and functions in steady state and pathological conditions. Macrophages predominantly infiltrate fibre-induced mesothelioma tumors and contribute to cancer development. Here, we revealed their ontogeny by comparing the response to needle-like mesotheliomagenic carbon nanotubes (CNT-7) with tangled-like non-mesotheliomagenic CNT-T. In a rat peritoneal cavity model of mesothelioma, both CNT induced a rapid macrophage disappearance reaction (MDR) of MHCIIlow resident macrophages generating an empty niche available for macrophage repopulation. Macrophage depletion after mesotheliomagenic CNT-7 was followed by a substantial inflammatory reaction, and macrophage replenishment completed after 7 days. Thirty days after non-mesotheliomagenic CNT-T, macrophage repopulation was still incomplete and accompanied by a limited inflammatory reaction. Cell depletion experiments, flow cytometry and RNA-seq analysis demonstrated that, after mesotheliomagenic CNT-7 exposure, resident macrophages were mainly replaced by an influx of monocytes, which differentiated locally into MHCIIhigh inflammatory macrophages. In contrast, the low inflammatory response induced by CNT-T was associated by the accumulation of self-renewing MHCIIlow macrophages that initially derive from monocytes. In conclusion, the mesotheliomagenic response to CNT specifically relies on macrophage niche recolonization by monocyte-derived inflammatory macrophages. In contrast, the apparent homeostasis after non-mesotheliomagenic CNT treatment involves a macrophage regeneration by proliferation. Macrophage depletion and repopulation are thus decisive events characterizing the carcinogenic activity of particles and fibres.

Expression of factor V by resident macrophages boosts host defense in the peritoneal cavity.

Macrophages resident in different organs express distinct genes, but understanding how this diversity fits into tissue-specific features is limited. Here, we show that selective expression of coagulation factor V (FV) by resident peritoneal macrophages in mice promotes bacterial clearance in the peritoneal cavity and serves to facilitate the well-known but poorly understood "macrophage disappearance reaction." Intravital imaging revealed that resident macrophages were nonadherent in peritoneal fluid during homeostasis. Bacterial entry into the peritoneum acutely induced macrophage adherence and associated bacterial phagocytosis. However, optimal control of bacterial expansion in the peritoneum also required expression of FV by the macrophages to form local clots that effectively brought macrophages and bacteria in proximity and out of the fluid phase. Thus, acute cellular adhesion and resident macrophage-induced coagulation operate independently and cooperatively to meet the challenges of a unique, open tissue environment. These events collectively account for the macrophage disappearance reaction in the peritoneal cavity.

Single-cell analysis reveals new subset markers of murine peritoneal macrophages and highlights macrophage dynamics upon Staphylococcus aureus peritonitis.

Resident macrophages play a central role in maintaining tissue homeostasis and immune surveillance. Here, we used single cell-based qPCR coupled with flow cytometry analysis to further define the phenotypes of large and small resident peritoneal macrophages (LPMs and SPMs, respectively) in mice. We demonstrated that the expression of Cxcl13, IfngR1, Fizz-1 and Mrc-1 clearly distinguished between LPMs and SPMs subsets. Using these markers, the dynamics of peritoneal macrophages in a Staphylococcus aureus-induced peritonitis model were analyzed. We found that S. aureus infection triggers a massive macrophage disappearance reaction in both subsets. Thereafter, inflammatory monocytes rapidly infiltrated the cavity and differentiated to replenish the SPMs. Although phenotypically indistinguishable from resident SPMs by flow cytometry, newly recruited SPMs had a different pattern of gene expression dominated by M2 markers combined with M1 associated features (inos expression). Interestingly, S. aureus elicited SPMs showed a robust expression of Cxcl13, suggesting that these cells may endorse the role of depleted LPMs and contribute to restoring peritoneal homeostasis. These data provide information on both resident and recruited macrophages dynamics upon S. aureus infection and demonstrate that single-cell phenotyping is a promising and highly valuable approach to unraveling macrophage diversity and plasticity.

Review of the macrophage disappearance reaction.

Macrophages (M phi s) undergo a physiological response known as the macrophage disappearance reaction (MDR) in response to certain stimuli in the peritoneal compartment. The types of stimuli that can cause the MDR, the relationship of the MDR to the host immunological response, and the possible role of the MDR in M phi activation are reviewed. The data indicate that the MDR occurs in response to both acute nonspecific inflammatory and specific immune delayed hypersensitivity processes and that the MDR may play an important role in M phi activation.

The tumor disappearance reaction: An in vivo effect of a noncytotoxic lymphokine active against tumor cells

A lymphokine, tumor migration inhibition factor (TMIF), that can inhibit the migration of tumor cells in vitro without cytotoxic effect has been described. TMIF can be produced in vitro or in vivo. In the present study, it is demonstrated that administration of TMIF can lead to a transient decrease in recoverable tumor cells from the peritoneal cavities of otherwise untreated mice. This result, which appears to be due to a direct effect of the mediator, rather than a consequence of inflammatory cell accumulation, is analogous to the effect of macrophage migration inhibition factor (MIF) on macrophages in the well known macrophage disappearance reaction. These findings demonstrate that TMIF can exert an effect in vivo predicted from its in vitro properties, and raise the possibility that this effect can be exploited in an appropriate therapeutic model.

Regulatory mechanisms of cutaneous delayed-type hypersensitivity: II. Suppression of cutaneous delayed-type hypersensitivity by macrophage disappearance reaction

Studies were performed on the behavior of cutaneous delayed-type hypersensitivity (DTH) in guinea pigs in which macrophage disappearance reaction (MDR) was induced. Guinea pigs were immunized with dinitrophenylated egg albumin (DNP-EA), followed by intraperitoneal (ip) injection of liquid paraffin in order to elicit peritoneal macrophages. Subsequently 20 μg of EA was injected into these animals and the animals were divided into two groups. One group of animls was sacrificed for estimation of MDR 6 hr after the subsequent ip injection. The other group received a skin test by EA at the time of the subsequent ip injection. The first group of animals sacrificed for estimation of MDR exhibited a marked reduction in the number of peritoneal macrophages. The second group of animals that received skin tests revealed suppressed skin reactions 24 hr after the subsequent ip injection. A similar experiment was performed using the guinea pigs doubly immunized with DNP-EA and dinitrophenylated bovine γ-globulin (DNP-BGG). Induction of MDR was performed by ip injection of BGG and skin tests were done by both EA and BGG. As a result, suppression of not only BGG-induced skin reactions but also EA-induced skin reactions was observed in animals in which MDR had been induced by BGG. In addition, the guinea pigs in which MDR was induced showed hyporeactivity to phytohemagglutinin (PHA). Reactivity to skin reactive factor (SRF) was also suppressed in these animals. The culture supernatants of macrophages incubated with the MIF fraction in vitro showed the ability to suppress skin reactions of cutaneous DTH, PHA and SRF.

Induction of macrophage disappearance reaction by immunoadsorbed MIF

The macrophage disappearance reaction (MDR) was induced by intraperitoneal (ip) injection of the immunoadsorbed macrophage migration inhibitory factor (MIF) fraction into the guinea pigs with macrophage-rich peritoneal exudates. The MDR induced by the immunoadsorbed MIF fraction was suppressed by α- l-fucose. Heparin, which is an anticoagulant drug, could also inhibit the MDR induced by the immunoadsorbed MIF fraction. Immunofluorescent study using fluorescein isothiocyanate (FITC)-labeled rabbit anti-human fibrinogen revealed the presence of fibrin/fibrinogen as an enveloping network pattern on the surface of macrophages during the course of MDR induced by the immunoadsorbed MIF fraction.

Macrophage migration stimulation factor.

Macrophage migration stimulation factor.

Additional evidence for the role of hyaluronic acid in the macrophage disappearance reaction.

A slight macrophage disappearance reaction was elicited in C3H/Hej mice, a low responder strain. Low levels of hyaluronic acid accumulated in the peritoneal fluid during the disappearance reaction, in keeping with the low response. The macrophage disappearance reaction was not simulated by the intraperitoneal injection of large amounts of hyaluronate into nonsensitized C3H/Hej mice. This suggested that these macrophages were refractory to hyaluronic acid. Subsequent experiments demonstrated that low concentrations of hyaluronic acid did not agglutinate these cells, in vitro, nor inhibit their migration to the extent obtained with macrophages from the responder mice (C57BL/6 strain), thus providing evidence that the low responder mice had at least two defects with respect to the disappearance reaction: 1) they accumulated less hyaluronic acid in their peritoneal fluid, and 2) their macrophages were refractory towards hyaluronic acid. Generalized defects in membranes of various cell types of C3H/Hej mice, involving receptors for lymphokines in the case of mesothelial cells, or hyaluronic acid receptors on macrophages may serve as the central defect and explain the above observations.

Participation of hyaluronic acid in the macrophage disappearance reaction.

Hyaluronic acid accumulates in the peritoneal cavity of mice during the macrophage disapperance reaction. Macrophages reappear in the exudates during the depletion of hyaluronate. The disappearance reaction is simulated by the intraperitional (i.p.) injection of hyaluronic acid into normal mice. The disapperance reaction largely is inhibited by the simultaneous injection (i.p.) of specific hyaluronidase with the challenge dose of BCG. We propose that hyaluronic acid makes a major contribution to the macrophage disappearance reaction.

Suppression of Cell-Mediated Immune Reactions by Monosaccharides

Various monosaccharides have been shown capable of inhibiting lymphokine activity in in vitro assay systems. In this study, we demonstrate that L-fucose can inhibit the ability of lymphokine-containing supernatants to induce skin reactions or cause reductions in the macrophage content of peritoneal exudates. Moreover, L-fucose can inhibit the cutaneous delayed hyoersensitivity reaction and the peritoneal macrophage disappearance reaction (MDR) induced by antigen in actively immunized guinea pigs. The effect of L-rhamnose, another sugar with in vitro inhibitory activity, was investigated in the MDR, and was also shown to be inhibitory. L-arabinose, which has no in vitro effects on lymphokines, had no suppressive effect on any of the in vivo systems studied. No monosaccharide inhibition of Arthus reactions or nonspecific inflammation could be found in these studies. The results demonstrate that monosaccharides capable of inhibiting lymphokine activity in vitro are effective in suppressing in vivo manifestations of cellular immunity.

The leucocoyte disappearance reaction in non-immune acute inflammation.

Injection of a variety of irritants (saline, ovalbumin, compound 48/80 and powdered glass) into the rat pleural cavity induced the disappearance of pleural leucocytes during the first two hours of the reaction. This phenomenon, termed the leucocyte disappearance reaction (LDR), was suppressed by treatment with the anticoagulants heparin and warfarin. The in-vitro incubation of normal, or inflammatory pleural leucocytes resulted in the deposition of dense interconnecting meshwork of fibrin only upon addition of fibrinogen to the culture medium. It is suggested from these results that the LDR is related to the clotting system, involving leucocyte-derived enzyme(s) analogous to those of the clotting system (e.g., tissue thromboplastin), which convert fibrogen to fibrin, resulting in cell-trapping and subsequent "disappearance" of pleural leuococytes. Similarities were observed betweeen the LDR in non-immune inflammation and the macrophage disappearance reaction of cell-mediated immunity. The significance of these phenomena in the inflammatory process, both immune and non-immune, is discussed.

Desensitization: II. Passive transfer of the desensitized state by serum from desensitized animals

The present study was undertaken in an effort to elucidate the mechanism(s) responsible for desensitization, making use of both cutaneous and peritoneal manifestations of delayed hypersensitivity as parallel assay systems in the guinea pig model. Particular emphasis was placed on investigating the possibility of passively transferring desensitization with serum factors and attempting to characterize these. Our data support the hypothesis of an inhibitory environment in the anergic animal: The desensitized state was successfully transferred to immune recipients by the systemic administration of desensitized serum as measured by both skin testing and macrophage disappearance reaction (MDR). Transfer of the desensitized state is not due to residual antigen in donor sera and is nonspecific. Partial characterization of the serum inhibitor indicated that it is nondialyzable, heatstable at 56 °C for 30 min, but destroyed by heating at 80 °C for 60 min. Sephadex G-100 chromatography located the inhibitory activity in the size range of 10,000–45,000 daltons. Larger molecular weight fractions were devoid of inhibitory activity, suggesting that antibodies or immune complexes are not responsible for the effect observed and the inhibitory serum component is not associated with macroglobulins. The physicochemical properties of the desensitizing factor, and our previous finding that intravenous injection of lymphokines leads to transient cutaneous anergy, suggest that the desensitizing substances may represent endogenous lymphokines in the general circulation.

Macrophage disappearance reaction induced by lymphokines.

Macrophage disappearance reaction was induced in normal (non-sensitized) guinea pigs by human lymphokines deriving from Con A-stimulated lymphocytes, by ellagic acid (an activator of intrinsic coagulation) and by thromboplastin (an activator of extrinisic coagulation). The results are discussed from the aspect of the pathomechanism of macrophage disappearance reaction.

The Macrophage Disappearance Reaction (MDR) as an in Vivo Test of Delayed Hypersensitivity in Mice

The macrophage disappearance reaction (MDR), as an invivo analogue of in vitro tests for delayed hypersensitivity, was utilized in mice with M. tuberculosis or mouse thyroid extract (MTE). The optimal schedule for the induction of macrophages in peritoneal exudates and the optimal concentration of antigen for the MDR were determined. Macrophage disappearance occurred 4 h after immunized mice received an intraperitoneal injection of 200 microng of soluble antigen. The MDR was found to be antigen specific. Intraperitoneal injection of an unrelated antigen or tissue culture medium alone did not cause macrophage disappearance; however, the re-injection of the antigen used for immunization caused a 70-80% reduction of macrophages. Macrophage disappearance was greater in mice immunized with M. tuberculosis than in mice immunized with MTE. Comparison of the MDR with the footpad test in these 2 groups showed that mice immunized with M. tuberculosis developed a higher degree of delayed hypersensitivity than the group immunized with MTE. These results demonstrate that the MDR represents a specific and quantitative method for detecting the delayed type of cellular immune response in mice.

Autoimmune murine thyroiditis. Relationship of humoral and cellular immunity to thyroiditis in high and low responder mice

Good responder (C57/Br/cd) and poor responder (C57BL/10) mice were immunized with mouse thyroid extract in Freund's complete adjuvant. The good responder mice first showed antibody to thyroglobulin on the seventh day while the poor responder animals had slightly lower titers and antibody did not appear until day 12. The first signs of thyroid infiltration appeared on day 4 in the responder strain, and severe lesions were seen between the third and fifth week. In contrast, the poor responder mice showed almost no evidence of infiltration. The macrophage disappearance reaction, a measure of cell-mediated immunity, was similar in the responder and nonresponder strains.

Desensitization: Effects on Cutaneous and Peritoneal Manifestations of Delayed Hypersensitivity in Relation to Lymphokine Production

Guinea pigs exhibiting delayed hypersensitivity may be desensitized by a single large dose of antigen administered intramuscularly. In the present experiments, desensitization with a soluble protein such as egg albumin (EA) or bovine gamma-globulin (BGG) was nonspecific in that they suppressed both cutaneous reactivity and the macrophage disappearance reaction (MDR) to unrelated antigen in doubly immunized animals. In contrast, myobacterial antigen, at the dose studied, showed limited specificity in that it could suppress the MDR but not a skin test to an unrelated antigen. Induction of an MDR was shown to be associated with the appearance of macrophage migration inhibitory factor (MIF) and chemotactic activity in the peritoneal exudate fluid. Pretreatment with desensitizing doses of mycobacteria prevented the EA-induced appearance of MIF in the peritoneal fluids. In contrast, chemotactic activity could still be recovered, even though the MDR was suppressed. Mycobacteria functioned as a specific desensitizer not only with respect to cutaneous reactivity, as stated above, but also with respect to the production of chemotatic factor by peritoneal exudate cells. In contrast, mycobacteria functioned as a nonspecific desensitizer with respect to both the MDR and MIF production. These results suggest that the MDR may be an in vivo manifestation of MIF activity, whereas the cutaneous delayed hypersensitivity reaction may be more dependent upon chemotactic activity. These observations reported here, taken in conjunction with previously described in vitro studies, suggest that desensitization is a complex phenomenon which may be the result of several different mechanisms acting separately or in concert. The apparent discrepancies in the literature as to whether or not desensitization is a specific process would appear to arise from differences in the experimental model and the particular antigen used.

The production of migration inhibition factor by B and T cells of the guinea pig.

Stimulation of sensitized lymphocytes by specific antigen in vitro leads to the production of migration inhibition factor (MIF). In the case of the pure soluble protein, or hapten-protein antigens used in the present studies, this MIF production was a property of the T lymphocytes in the cell suspensions. When PPD was used, B cells, as well as T cells, produced MIF. Similarly, PPD could stimulate B cells to mediate the macrophage disappearance reaction, a reaction which is known to be a T cell-dependent in vivo manifestation of cell-mediated immunity. Suspensions of lymphocytes from nonimmune donors could also be stimulated by PPD; in this case, B cells, but not T cells, produced MIF. The factors produced by the two lymphocyte subpopulations appeared to be similar, if not identical, on the basis of physico-chemical criteria. It is suggested that PPD stimulates B cells for MIF production because of its role as a B cell mitogen. The ability of endotoxin lipopolysaccharide, another B cell mitogen, to also induce MIF production by B cells supports this contention. Thus, although activation of lymphocytes for MIF production by specific antigen is a property of T cells, B cells as well as T cells may be so activated by agents which act nonspecifically. This may prove to have implications for in vivo events involved in immunization. In addition, these observations lend further support to the concept that lymphokine production represents a general biologic phenomenon in addition to playing a role in the effector mechanisms for reactions of cell-mediated immunity.