Leukocyte-migration inhibition in guinea pigs. I. Correlation with skin test reactivity and macrophage-migration inhibition.

Fifteen guinea pigs, immunized with one of three soluble antigens, repeatedly demonstrated inhibition of leukocyte migration and positive skin tests to the immunizing antigens. An additional five animals immunized with ovalbumin demonstrated inhibition of macrophage migration as well as direct and indirect inhibiton of leukocyte migration. Only one of fifteen animals demonstrated inhibition of leukocyte migration and none had a positive skin test with an antigen to which it had not been sensitized, indicating that the assay is antigen specific.     

Study of Delayed Hypersensitivity to Myxoviruses Induced by Vaccines

The delayed hypersensitivity response of guinea pigs to Bacillus Calmette-Gúerin (BCG) and myxovirus vaccines was investigated by use of the techniques of skin testing and inhibition of macrophage migration. A serum antibody response to the injected vaccines was readily demonstrable. Parainfluenza type 2 virus consistently failed to induce a delayed hypersensitivity state in 15 animals, even with the use of a virus adjuvant emulsion. Respiratory syncytial virus occupied an intermediate position in that positive delayed type skin tests of an erythematous nature were elicited following inoculation, but only two of seven guinea pigs yielded a positive migration inhibition test. In mumps-inoculated animals, skin testing gave rise to erythematous delayed skin reactions which varied from 0 to 20 mm in size. Migration inhibition could be demonstrated in 7 of 21 animals. In almost all guinea pigs inoculated with BCG, large, indurated, erythematous skin reactions were elicited, and inhibition of macrophage migration was readily demonstrated. The degree of skin reactivity was positively correlated with inhibition of macrophage migration. If the skin reaction to a specific antigen exceeded 9 mm of erythema, that antigen also inhibited macrophage migration. Skin testing proved to be the most sensitive indicator of viral hypersensitivity. Migration inhibition was demonstrated only when a greater than 8-mm skin reaction was evoked. This cellular hypersensitivity appeared to be a qualitative phenomenon, the expression of which could be heightened by the use of adjuvant. The applicability and sensitivity of the migration inhibition technique is considered relative to its use for in vitro monitoring of effects of viral vaccine inoculations.     

Effect of C-reactive protein on peritoneal macrophages. I. Human C-reactive protein inhibits migration of guinea pig peritoneal macrophages

The effect of human C-reactive protein (CRP) isolated and purified from pooled patients' sera on macrophage function, especially on macrophage migration, was studied. Peritoneal exudate cells (PEC) from guinea pigs were used for macrophage migration inhibition (MMI) test of capillary method. Migration of either PEC or adherent purified macrophages exposed to CRP were inhibited dose-dependently. These findings indicate that CRP inhibits macrophage migration directly, not via activation of lymphocytes contained in PEC. As control, we examined the effect of normal human serum, anti C-polysaccharide antibodies isolated from patients' sera, and free endotoxin at the dose contaminated in CRP preparation on macrophage migration and found that none of them were effective. The effect of CRP on MMI of sensitized PEC exposed to antigen was also studied. Large amounts of CRP inhibited MMI induced by antigen, indicating the possibility that CRP may act on macrophages competitively with migration inhibitory factor (MIF) and may modulate MMI. CRP possesses MIF-like activity and may play a functional role at the site of tissue injury by causing the accumulation of macrophages.     

In Vitro Assay of Endotoxin by the Inhibition of Macrophage Migration

A quantitative in vitro technique was used to compare the ability of different endotoxins to inhibit the migration of macrophages from explants of rabbit spleen cultured in a coagulated plasma medium. The order of potency was different from that observed in chick embryo assays, and in assays with mice, of the same endotoxins. In general, however, the sensitivity of the macrophage inhibition test was comparable to that of other bioassay methods. A highly purified endotoxin from Salmonella enteritidis (Ribi) in a concentration of 0.004 mug/ml regularly inhibited macrophage migration. The in vitro method was used to detect a progressive loss of biological activity in fractions obtained during acid hydrolysis of the purified endotoxin. The selective toxicity of very low concentrations of endotoxin for mammalian macrophages was important in estimating the degree of specificity of the reaction. The pattern of cellular response in explant cultures made it possible to differentiate endotoxic damage from the specific cytotoxic action of antigen associated with delayed hypersensitivity.     

Migration inhibition test with thyroid membrane antigen in Graves-Basedow disease and nodular goiter]

The evaluation of the migration inhibition test with thyroid membrane antigen was carried out in 20 patients with Graves' disease, 13 patients with neutral nodular goiter and 13 healthy subjects. A significant inhibition of migration by thyroid antigen as compared to the control group was demonstrated only in the patients with Graves' disease (the value of the migration index was 0.57 +/- 0.07). The respective value was 0.79 +/- 0.16 in patients with nodular goiter and 0.85 +/- 0.11 in healthy subjects. The results obtained indicate the practical value of the migration inhibition test in diagnosing the thyroid diseases having an autoimmune background.     

Mastocytoma cell migration in vitro: inhibition by MIF-containing supernatants.

Supernatants with macrophage migration inhibition factor (MIF) activity were obtained from cultures of antigen-stimulated guinea pig and human lymphocytes, and from SV40-infected monkey kidney cells. The monkey and human but not guinea pig preparations were effective in inhibiting migration of mastocytoma cells as well as macrophages. This inhibition of migration was not associated with cytotoxicity and was reversible.     

Leukocyte migration inhibition test (LMIT) in systemic lupus erythematosus.

A leukocyte migration inhibition test (LMIT) utilizing the agarose gel technique was performed with native DNA as an antigen in ten patients with systemic lupus erythematosus (SLE) and five normal subjects. Irrespective of disease activity, supernatants obtained at different time intervals during lymphocyte culture in eight patients with SLE showed significant alteration of migration, either enhancement or inhibition, of normal leukocytes. However, supernatants in the control experiments produced no significant alteration of migration. Polyacrylamide gel electrophoresis of supernatants obtained from the SLE group revealed that the inhibitory activity was present in the albumin region, whereas the enhancement activity was found in the beta-globulin region. These results indicate that the hitherto employed estimation of the leukocyte migration inhibition test based on the total activity of these two factors is insufficient for accurate evaluation of chemical mediators from sensitized lymphocytes and that the separation of these two factors may be important for a greater understanding of cellular immunity.     

The phenotypic expression of the genes controlling the yield of a factor suppressing macrophage migration to Candida albicans antigens and tuberculin in mice

The regulation of the synthesis of factor inhibiting the migration of macrophages in response to C. albicans antigen in CBA (H-2k) and C57BL/6 (H-2b) mice has been studied. The low level of macrophage migration inhibition factor in response to this antigen is due to the existence of cyclophosphamide-inhibited specific suppressors. Differences between various strains of mice ensue from different activity of suppressors of thymic origin, whose nature has been revealed as the result of the transfer of marrow cells treated with anti-Thy-1 serum.     

Immunotoxicity of phosphamidon following subchronic exposure in albino rats

Effect of subchronic doses of phosphamidon exposure on humoral and cell mediated immune (CMI) responses were studied in male albino rats using SRBC, ovalbumin and KLH as antigens. Humoral immune responses were assessed by estimating antibody titre against antigen and splenic plaque forming cells (PFC) assay. CMI responses were studied by using leucocyte migration inhibition (LMI), macrophage migration inhibition (MMI) and delayed type hypersensitivity (DTH) response. Results obtained in the present study revealed marked suppression of humoral and CMI responses in a dose dependent pattern. Hence, suppression of immune responses by phosphamidon even at subchronic doses is clearly an important aspect for its safety evaluation.     

Macrophage Migration Inhibition by Serum from Desensitized Animals Previously Sensitized with Tubercle Bacilli

MIGRATION of peritoneal exudate cells removed from guinea-pigs or mice exhibiting delayed hypersensitivity is inhibited by specific antigen^1–3. This in vitro macrophage migration inhibition has been regarded as a useful immunological test for delayed skin hypersensitivity^4,5. Studies of the mechanism of this phenomenon revealed that, in contact with specific antigen, lymphocytes from sensitized animals released into the medium a specific substance (migration inhibitory factor; MIF) capable of inhibiting the migration of normal macrophages^6,7. When injected intradermally into normal guinea-pigs, MIF elicits inflammatory reactions characterized by induration, erythema and mononuclear cell infiltration⁸.     

Macrophage migration stimulation factor, migration inhibition factor and the role of suppressor cells in their production.

Guinea pig lymph node lymphocytes and human peripheral blood lymphocytes when stimulated by specific antigen or mitogen will release factors that affect in vitro macrophage migration. Migration inhibition factor production appears to be under the control of suppressor cells which are T lymphocytes. When suppressor cells are generated by stimulation with Con A for 4 days, migration stimulation factor (M.St.F.) activity is found. In other situations where M.St.F. is found this is thought to be due to increased suppressor cell activity. For example, young adults produce this lymphokine when stimulated with Con A, whereas aged individuals produce MIF. Concanavalin A appears to be the mitogen of choice for M.St.F. production, and phytohemagglutinin for MIF production. The release of this putative factor M.St.F. from suppressor T cells helps to explain some of the difficulties that have existed in studies of macrophage migration inhibition.     

Immune Response against Hamster Erythrocytes in the Low-Responder Mouse Strains

Delayed hypersensitivity against hamster erythrocyte antigen was examined after sensitization with hamster erythrocytes (HRBC) in Freund's complete adjuvant (FCA). Extent of the delayed hypersensitivity was determined by the migration inhibition test, the peritoneal macrophage disappearance test and the skin test in the ear using solubilized HRBC as the test antigen. 1) Delayed hypersensitivity against HRBC developed earlier in high-responder SL mice than in low-responder C57BL/6 mice after sensitization. The period required for development of the delayed hypersensitivity in AKR mice was intermediate between periods in high-responder SL mice and low-responder C57BL/6 mice. 2) After sensitization with HRBC in FCA, a delayed hypersensitive state without detectable antibody production persisted until day 12 in high-responder SL mice and until day 16 or later in low-responder C57BL/6 mice. 3) Delayed hypersensitivity against HRBC antigen persisted even after the appearance of circulating antibody which occurred late after sensitization with HRBC in FCA or after intravenous injection of HRBC into sensitized mice.     

Changes in macrophages in vivo induced by desensitization.

Peritoneal exudate macrophages were removed from animals sensitized to horse cytochrome c and from similar animals which had been desensitized with this antigen. The ability of lymphokine to induce migration inhibition and also alterations of the level of glucose oxidation in these cells has been examined. It was found that for a transient period after the desensitization, macrophages removed from the peritoneum were unresponsive to lymphokine in the migration inhibition assay. At the same time, culturing these cells with lymphokine for 1 hr caused a significant rise in their glucose oxidation activity. It is suggested from these results that desensitization may result in macrophage activation in vivo. This is discussed in relation to current concepts of the mechanisms of desensitization.     

Cell-mediated Immunity in Herpesvirus hominis Infections

The cell-mediated and antibody responses to Herpesvirus hominis type 1 were investigated in patients with primary and recurrent herpetic infections. Stimulation of lymphocyte transformation with the virus and the complement fixing antibody titre did not differ significantly between patients and controls. However, macrophage migration inhibition and lymphocyte cytotoxicity were impaired in patients. The defects were specific to H. hominis, as Candida oblicans, which was used as an unrelated antigen, failed to show a similar abnormality. These results and preliminary sequential studies suggest that the susceptibility to recurrent herpesvirus infection may be due to an impaired production of macrophage migration inhibition factor and lymphocyte cytotoxicity in the presence of intact lymphocyte sensitization and antibody formation.     

Leukocyte procoagulant activity in man: an in vitro correlate of delayed-type hypersensitivity

Human mononuclear leukocytes generate cell-bound procoagulant activity (LPCA) after incubation with an antigen (mumps or tuberculin) to which the donor was previously sensitized. An inhibitor of coagulation appears to be liberated into the extracellular culture fluid during incubation of leukocytes with the sensitizing antigen. Removal of this activity before measuring LPCA resulted in a reliable test that correlated directly with delayed skin reactivity. The assay was particularly sensitive in that cells from weakly sensitized donors who reacted only to high doses of tuberculin (100 TU) in the delayed skin tests produced detectable LPCA in vitro. By contrast cells from weakly sensitized donors did not react to PPD in the lymphocyte blast transformation test or the direct macrophage migration inhibition factor test. The LPCA assay correlated closely with the blast transformation and MIF tests in which cells were used from more strongly sensitized donors who reacted in skin tests with lower doses of tuberculin (1 or 10 TU). The assays were antigen-specific in that cells from donors sensitive to mumps antigen but not to tuberculin reacted only to mumps antigen in vitro. The assay was extremely reproducible; cells from individual donors reacted to the same extent over a period of 8 mo). We propose that the assay system reported here represents an improved method for the measurement of cell-mediated immunity in vitro because it requires fewer donor cells, is technically simpler, and is more sensitive than previously described methods.     

Radiation leukemia virus-transformed immunocompetent T cells. II. Antigen-induced macrophage migration inhibition factor and leukocyte migration inhibition factor production

OVA-specific T cells were immortalized by infection with radiation leukemia virus (RadLV). Some clones derived from such population were shown to exhibit helper activity. We then tested clones without such function and found among them some that secreted macrophage migration inhibition factor (MIF) and leukocyte migration inhibition factor (LIF) upon exposure to the antigen in vitro. The lymphokine-producing clones, which were Thy-1+, Ly-1+ and Ly-2-, did not secrete MIF and LIF constitutively. Like other antigen-specific T cells, the immortalized clones could not be stimulated by free soluble antigen but required macrophages for presentation and for triggering the lymphokine production. The antigen-activated clones exclusively produced MIF and LIF, but not interleukin 2 or colony-stimulating factor. They neither provided helper activity nor induced delayed-type hypersensitivity. The data suggest that the T-cell clones carry the antigen receptors and that their antigen-inducible biological function is restricted to the migration inhibitory factor production.     

The utility of the macrophage migration inhibition test for in vitro titration of tuberculins

The purpose of this study was to explore the fundamental principle of the potency estimation of tuberculins, as applied in vitro by the macrophage migration inhibition test (MIT) under agarose. The MIT was performed using specifically sensitized mouse and guinea-pig peritoneal macrophages and serial dilutions of the analogous PPD (purified protein derivatives of tuberculin) tuberculins as antigen. Statistical studies performed included (a) the standard deviation of the mean migration areas, (b) the analysis of variance, (c) the regression analysis, (d) its corresponding linearity test and (e) the determination of the related correlation coefficient. It was shown for the first time and in both animal species under study that there is correspondence between the log dose-response relationship of the tuberculin PPD in MIT under agarose and the well known in tuberculin cutaneous reaction. The MIT may therefore successfully replace the in vivo titration of tuberculins.     

Stimulation of phagocytic function by factors inhibiting leukocyte and macrophage migration in humans

Fractions containing macrophage migration inhibition factor (MIF) and leucocyte migration inhibition factor (LIF) were obtained using Sephadex G-200 filtration from supernatant fluids of human lymphocyte cultures stimulated by PHA. The fractions were tested for the ability to affect migration and phagocytic activity of target cells. Peripheral blood leucocyte migration capacity was inhibited by the fraction with the molecular mass of 60,000-70,000 D (LIF), while migration activity of mouse peritoneal exudate cells was suppressed by the fraction with the molecular mass of 20,000-30,000 D (MIF). MIF- and LIF-containing fractions increased almost three-fold Fc-receptor-mediated phagocytic activity of neutrophils.     

Guinea pig macrophage agglutination factor is antigenically distinct from migration inhibition factor and immunoglobulin.

Lymph node cells from guinea pigs with specific delayed hypersensitivity release macrophage agglutination (MAggF) and migration inhibition factors (MIF) upon exposure to antigen or concanavalin A in serum-free medium. MAggF in culture supernatants was absorbed neither by immunoabsorbents made with a rabbit anti-guinea pig lymphokine serum that removed MIF, nor by immunoabsorbents made with rabbit anti-guinea pig Ig. These results suggest that MAggF is antigenically distinct from MIF and Ig.     

Skin Reaction and Macrophage Migration Inhibition Tests for Polysaccharides from Aspergillus fumigatus and Candida albicans

Guinea pigs sensitized with purified galactomannan from Aspergillus fumigatus and mannan from Candida albicans, each containing negligible quantities of nitrogen, were examined for their immunological responses against the corresponding polysaccharides with respect to the delayed-type skin reaction and the macrophage migration inhibition phenomenon. In both cases, the delayed-type skin reaction test and the macrophage migration inhibition test showed positive results. The reactivity was stronger in animals sensitized with polysaccharides in Freund's complete adjuvant than those sensitized with the same polysaccharides in Freund's incomplete adjuvant. Polysaccharides chemically modified by partial acid degradation or by periodate oxidation were found to be completely incapable of eliciting such immune responses. These results are also discussed in relation to the antigenic determinant of the polysaccharides in such immune responses and the precipitin reaction previously observed by us and other investigators.