Leukocyte migration inhibition factor production in marasmic infants.

Production of leukocyte migration inhibition factor was measured in vitro with purified protein derivative and phytohemagglutinin in 14 marasmic infants 6 to 18 months of age. Twenty-seven well-nourished infants served as controls. All the children had received BCG vaccine in the neonatal period. Tuberculin reaction was positive in four of 14 of the marasmic infants and 13 of 27 of the controls. When leukocyte migration inhibition factor was induced with purified protein derivative, the four tuberculin positive malnourished subjects had a mean migration inhibition index of 55.7% which was significantly higher than the mean migration inhibition index of 38.2% in the tuberculin positive controls. In the tuberculin negative subjects the mean migration inhibition index was 24.7 and 16.6% in the marasmic and control groups, respectively. The difference was not statistically significant. Phytohemagglutinin-induced migration inhibition was comparable in malnourished and control infants. There was no correlation between leukocyte migration inhibition factor production and biochemical indices of iron nutrition, erythrocyte or serum folate, vitamin A, carotene, or serum zinc levels in either group. It is suggested the capacity of lymphocytes to produce leukocyte migration inhibition factor is unchanged in marasmus.

Studies on migration inhibitory factors of non-lymphoid origin.

A large number of mouse fibrosarcoma and adult guinea pig fibroblast cultures were examined for their ability to produce migration inhibitory activity. In most cases culture supernatants were found to inhibit macrophage migration, in a dose-dependent manner. Toxicity of the tested material could be excluded by: a) experiments using colchicine as a stimulator of macrophage migration and, b) examination of the effect of test materials on macrophage monolayer cultures. Additionally, migration inhibitory activity was found in fibroblast, but not fibrosarcoma frozen and thawed extracts. Furthermore, incubation of cells with puromycin could only inhibit production by fibrosarcoma, thus suggesting that the fibroblast activity was due to preformed cellular constituents. Fractionation of concentrated culture supernatants by Sephadex G-200 gel filtration showed that the activity derived from fibrosarcoma cells could be eluted in a narrow molecular weight fraction (18,000-22,500), whereas the fibroblast activity was heterogenously distributed over a wide range. Migration inhibitory activity in fibroblast extracts was mainly associated with higher molecular weight material. Differences could be demonstrated between these activities and lymphocyte migration inhibitory factor, including inhibition by methyl-pentoses and the presence of macrophage aggregating activity.

In vitro induction of chronic myeloid leukemia associated immune reactivity in normal human lymphocytes by xenogeneic immune RNA.

Peripheral blood lymphocytes from normal human donors were treated with immune RNA (IRNA) prepared from lymphoid tissues of guinea pigs immunized with chronic myeloid leukemia (CML) cells, normal leukocytes (WBCs) and normal bone marrow (BM) cells, in order to study whether IRNA can confer specific immunoreactivity on normal lymphocytes. The IRNA treated lymphocytes were further exposed to solubilized membrane antigens from CML cells, normal WBCs and BM cells in a criss-cross fashion. The migration inhibition factor produced by these lymphocytes was tested in an in vitro leukocyte migration inhibition assay using normal leukocytes. The results indicated that IRNA prepared from guinea pigs immunized with all the three cell types could transfer the immune reactivity to normal cells in response to the respective antigens. The WBC IRNA incubated lymphocytes did not react with BM cell and CML cell antigens. A potent transfer of specific reactivity was shown by CML IRNA. IRNA produced against BM cells and CML cells demonstrated considerable cross reactivity perhaps due to shared immature cell antigens.

Cell-mediated and humoral immune responses of German Shepherd Dogs and Beagles to experimental infection with Ehrlichia canis.

The cell-mediated and the humoral immune responses of 12 German Shepherd Dogs and 5 Beagles inoculated with Ehrlichia canis were evaluated. Results indicated that specific and nonspecific immunosuppression due to E canis occurred in the German Shepherd Dogs. Canine leukocyte migration-inhibition factor was successfully isolated and shown to be physically and functionally similar to human and guinea pig migration inhibition factor. Of the German Shepherd Dogs, 58% developed positive cell-mediated responses; 80% of the Beagles became positive. German Shepherd Dogs that developed severe chronic ehrlichiosis did not respond to as great a degree as did the German Shepherd Dogs and Beagles with mild chronic disease. The cell-mediated responses decreased with time and disappeared by 147 days after inoculation. Humoral antibody titers in all inoculated dogs increased with time and remained at increased concentrations. Treatment of four inoculated dogs with antilymphocyte serum did not modify the course of the disease. The findings indicated that cell-mediated immunity may have a significant role in determining the course of disease in dogs infected with E canis.

Modulation of lymphocyte migration by human lymphokines. III. Characterization of a lymphocyte migration inhibitory factor (LyMIF35K).

The lymphokine that augments the migration of nonsensitized T lymphocytes (LCF) has been observed to be predominantly a chemokinetic factor, suggesting that separate lymphocyte migration inhibitory lymphokine(s) might exist. Utilizing a modified Boyden chamber assay, lymphocyte migration inhibitory activity was identified in the culture supernatants of human nylon wool-nonadherent blood mononuclear cells stimulated with concanavalin A in vitro for 48 hr. Sephadex G-100 gel filtration chromatography of these culture supernatants was shown to contain two regions of noncytotoxic migration inhibitory activity for nonsensitized human blood lymphocytes and rat splenic lymphocytes. The 30-40,000 dalton inhibitory activity was further characterized and noted to be cationic by ion-exchange chromatography and isoelectric focusing (pI = 8.6). Its biologic activity was sensitive to neuraminidase and to heat treatment but not to trypsin. The migration inhibitory activity of this factor (LyMIF35K) was directly proportional to its ability to increase lymphocyte adherence.

Regulation of lymphocyte motility by macrophages: characterization of a lymphocyte migration inhibitory factor derived from a macrophage-like cell line.

An inhibitory factor on lymphocyte migration was detected using a capillary random migration assay in the culture supernatant of peritoneal exudate macrophages cultured at concentrations greater than 8 x 10(6) cells/ml. After examining different macrophage-like cell lines, J774A.1 cells were found to produce this inhibitory factor, which was termed lymphocyte migration inhibitory factor (LMIF). The inhibitory effect of LMIF on the migration of spleen lymphocytes, thymocytes, and bone marrow cells was determined. The migration of thymocytes was more sensitive to LMIF than was the migration of spleen lymphocytes and bone marrow cells. Interestingly, when the effect of LMIF was tested on the migration of spleen T cells and B cells, T cells were more sensitive than B cells. When the thymocytes were separated by peanut agglutinin into mature and immature thymocytes, the migration of mature thymocytes was more sensitive than that of immature thymocytes, the migration of mature thymocytes was more sensitive than that of immature thymocytes to the effect of LMIF, suggesting that the greatest effect of LMIF was on the migration of mature T cells. Partial purification of LMIF by ion-exchange and gel-filtration chromatography revealed that it is approximately 14,000 in molecular weight and could exist in either monomeric or dimeric forms. The possible role of this factor in an immune response is discussed.

Partial purification and physicochemical properties of human T cell migration inhibitory factor (TIF).

Supernatants from 24 hr cultures of PHA-pulsed human T lymphocytes inhibit the migration of human peripheral blood T lymphocytes and guinea pig macrophages in vitro. The factor responsible for the inhibition of T lymphocytes provisionally called TIF (T cell migration inhibitory factor) was separated from MIF by preparative PAGE, had apparent molecular weight (m.w.) of 1,000-10,000 daltons and isoelectric point of 3.1. TIF activity was resistant to treatment with trypsin, chymotrypsin and neuraminidase but sensitive to PMSF (phenyl-methyl-sulfonyl-fluoride). This suggests that TIF is presumably different from human MIF and may represent a novel lymphokine which preferentially affects T cell migration in vitro.

Migration inhibition caused by EBV-specific 48K subcomponent of EBNA and the associated 53K cellular protein.

Leukocytes from EBV-seropositive but not seronegative healthy donors responded with significant migration inhibition to the 48K subcomponent of the Epstein-Barr virus determined nuclear antigen (EBNA), known to carry the virally determined antigenic specificity. A concentration of 10 micrograms/ml was still effective while 5 micrograms/ml had no detectable effect. EBNA-associated cellular 53K protein had no effect by itself, but it potentiated the effect of 48K, even if the latter was added at the subliminal concentration of 5 micrograms/ml. The related 53K protein, isolated from EBV-negative human lymphoma cells, was also effective, whereas the corresponding murine-tumor-associated 53K had no potentiating effect. Immunization of mice with an extract of DNA-binding proteins from EBV-carrying Raji cells, known to contain both 48K and 53K, induced a significant macrophage migration inhibition response, to both human 48K and 53K. Murine 53K was ineffective, however. Human but not murine 53K increased the migration inhibitory activity of subliminal concentrations of 48K in the murine macrophage system as well. These findings suggest that human but not murine 53K may reconstitute with 48K (EBNA) to form a highly immunogenic complex.

[Monocyte locomotion inhibiting factor (MLIF) produced by E. histolytica induces an increase of cAMP in human monocytes]. / El factor inhibidor de la locomoción de monocitos (FILM) producido por E. histolytica induce aumento del AMPc en los monocitos humanos.

The supernatant fluid of axenically grown E. histolytica contains a factor (MLIF) which inhibits the locomotion of human monocytes (including chemotaxis) without affecting that of human polymorphonuclear leucocytes. Locomotion, like other cellular functions, is modulated by changes in intracellular cAMP and cGMP. The consensus--with some exceptions--is that while rises in cGMP accompany locomotion, an increase in cAMP (without a concomitant fall in -cGMP) occurs with inhibition of cellular movement. We measured by radioimmunoassay the cAMP concentration of human monocytes exposed to inhibitory concentrations of MLIF. A significant (p less than 0.005) rise in monocyte cAMP was found, comparable to that observed with the use of forskolin, a well known cAMP stimulator. The control studies using plain axenic medium, not only failed to reveal any rise in cAMP but disclosed a small, yet not significant drop in intracellular cAMP. These results suggest that MLIF (like other locomotion inhibitors, i.e. prostaglandins E1, A1 and isoproterenol) produces a significant increase in intracellular monocyte cAMP. This modification in intracellular signals may contribute to the inhibition in monocyte locomotion, an event during which an increase in pericentriolar microtubules has also been observed.

Use of benzoyl-L-phenylalanyl-L-valyl-L-arginine (3H) methyl ester as a sensitive and selective substrate for the human lymphokine, leukocyte migration inhibitory factor (LIF).

Human leukocyte migration inhibitory factor (LIF) appears to be a serine esterase and protease exhibiting specific affinity towards arginine esters and amides. On the basis of indirect evidence that an amide of the oligopeptide benzoyl-phenylalanyl-valyl-arginine might have high and selective affinity for LIF, we prepared an ester of this oligopeptide, benzoyl-phenylalanyl-valyl-arginine (3H) methyl ester (3H-BPVAME) for the direct measurement of LIF activity in a double-phase radio-enzyme assay. The hydrolysis of 3H-BPVAME followed enzyme-substrate kinetics in that the reaction was time-, temperature-, pH-, and concentration-dependent. 3H-BPVAME rpoved to be more selective and approximately 20 times more sensitive as a substrate for LIF than previously used radiolabeled substrates such as 3H-BAEE and 3H-TAME. Moreover, hydrolysis of 3H-BPVAME by partially purified LIF preparations was significantly inhibited by 10(-8) to 10 (-5) M of guanosine 3',5'-cyclic monophosphate (cGMP), further supporting the hypothesis that cGMP acts as a regulator of LIF activity. Inhibition of LIF-induced esterolysis was also provided by dibutyryl cGMP, but only at concentrations 10(-7) to 10(-5) M; 8-bromo cGMP and adenosine 3',5'-cyclic monophosphate were both ineffective. These results provide support for the use of 3H-BPVAME as a more selective substrate to detect esterase activity in LIF preparations than heretofore described and the possible development of a biochemical assay for the measurement of this lymphokine.

Physiochemical characterization of lymphocyte inhibitory factor (LyIF) isolated from avian B and T cells.

Thymic (T) or bursal (B) lymphocytes from chicks sensitized to Mycobacterium tuberculosis produce an avian lymphocyte inhibitory factor (LyIF). The physiochemical properties of both T and B LyIF were established by ultrafiltration which yielded four fractions with molecular weight ranges of greater than 100,000; 50,000-100,000; 10,000-50,000; and less than 10,000; enzymatic treatment with chymotrypsin and neuraminidase; varying pH; and heat exposure. These studies demonstrated that the maximum activity for both T and B LyIF was within a molecular weight range of 10,000-50,000. Both were sensitive to chymotrypsin and neuraminidase treatment. Both were stable at 56 degrees C for 30 min and resistant to changes in pH from 5 to 9. T-Cell migration was inhibited equally by B or T LyIF, while B-cell migration was inhibited to a lesser extent by T LyIF and B LyIF. Further experiments should establish the reasons for these observed differences in cross-reactivity.

Determination of the human lymphokine leukocyte migration inhibitory factor (LIF) by a sensitive radioenzymatic assay. Inhibitory effect of cGMP on the esterolytic activity of highly purified LIF.

Indirect experiments using irreversible enzyme inhibitors have shown that the human lymphokine leukocyte migration inhibitory factor (LIF) is a serine esterase and protease exhibiting specific affinity towards arginine esters and amides. A sensitive assay for direct measurement of esterase activity using p-tosyl-L-arginine (3H) methyl ester (3H-TAME) as substrate is described. Esterolytic activities are demonstrated in crude supernatants of human lymphocytes stimulated with concanavalin A (LIF-rich) and, more pronounced, in supernatants of unstimulated cells (control). To follow the effects of purification procedures, the serine esterases of LIF-rich and control preparations were specifically labeled with the irreversible, active site directed agent (1,3-3H)di-isopropylphosphorofluoridate. Most of these enzymes, visualized by Sephadex chromatography, were removed by a gentle three-step procedure, allowing at least 50% of the initial LIF activity to be recovered. The resulting LIF-rich preparation, purified to contain serine esterases at a concentration corresponding to less than 1 ng per ml original supernatant, still showed estrolytic activity towards 3H-TAME. The optimal conditions for the radioenzymatic assay of purified LIF and the inhibitory effect of 10(-4) M cGMP, which on the basis of indirect experiments has been implicated as a specific regulator of LIF activity, are described.

Polymorphonuclear leukocyte-inhibitory factor of Bordetella pertussis. II. Localization in the outer membrane.

The outer and inner membranes and cytoplasm of spheroplasts of a strain of phase I B. pertussis were fractionated by density gradient centrifugation. The high density vesicles of the outer membranes isolated had the "Pili" characteristic of the bacteria and the same antigenicty as the bacterial surface. Activities for inhibition of polymorphonuclear leukocytes were also almost exclusively localized in this outer membrane fraction. The histamine-sensitizing activity was more dispersed, but its specific activity was also highest in the outer membrane fraction. These results suggest that molecules carrying these activities, which are probably different entities together with the tissue-adhesive pili, form a virulence complex on the surface of phase I organisms of B. pertussis.

Antigen-independent leukocyte random locomotion inhibitory activity in human ultrafiltrated leukocyte extracts.

Human ultrafiltrated leukocyte extracts (MW less than 5000) were fractionated by Sephadex G-10 column chromatography and the effects of these fractions on leukocyte random locomotion were investigated in vitro. Fr-4, one of these fractions, had significant leukocyte random locomotion inhibitory activity, independent of the presence of mononuclear leukocytes. This inhibitory activity was not due to cytotoxic effects on leukocytes. As seen by scanning electron microscopy, the number of cell surface pseudopods on leukocytes incubated with Fr-4 was reduced. Fr-4A, one of three fractions separated from Fr-4 by Sephadex G-25 column chromatography, significantly inhibited leukocyte random locomotion. Fr-4A contained numerous components, one of which was identified as 2-deoxyribose, on the basis of thin-layer chromatography. Biologically 2-deoxyribose showed an inhibitory effect on leukocyte locomotion and a reduction of the extrusion of pseudopods on the surface of leukocytes, at the range of assayed concentrations. This inhibitory activity is probably derived from 2-deoxyribose.

Functional characteristics of histamine receptor-bearing mononuclear cells. II. Identification and characterization of two histamine-induced human lymphokines that inhibit lymphocyte migration.

Although functional histamine receptors have generally been restricted to those human T lymphocytes expressing suppressor cell functions, more recent evidence suggests that histamine receptor-bearing human T lymphocytes are functionally heterogeneous and capable of other immunomodulatory activities. Lymphocyte chemoattractant factor (LCF) is a cationic sialoprotein with an apparent m.w. of 56,000, whose production is limited to histamine-type 2 receptor-bearing human T cells. LCF is selectively chemokinetic for T lymphocytes, and presumably contributes to the recruitment of unsensitized effector lymphocytes at inflammatory sites. In addition to LCF, Sephadex G-100 gel filtration of histamine-induced lymphocyte supernatants revealed two regions of migration inhibitory activity for human blood T and rat splenic lymphocytes. These regions corresponded to m.w. of 70,000 to 80,000 (LyMIF75K) and 30,000 to 40,000 (LyMIF35K). LyMIF75K had a single pI of 7.5 to 8.0, and its biologic activity was sensitive to trypsin but not to neuraminidase or heat (56 degrees C). LyMIF35K had a single pI of 8.5 to 8.8, and its biologic activity was sensitive to neuraminidase and heat but not to trypsin. These LyMIFs therefore appeared to be distinct from one another and physicochemically different from other migration inhibitory lymphokines. All three lymphokine activities appeared within 4 hr of incubation. The minimum concentration of histamine required to stimulate production of the LyMIF was 10(-6) M. Lymphocytes that did not adhere to a histamine affinity matrix were unable to produce either LyMIF upon subsequent stimulation with histamine or concanavalin A (Con A). Lymphocytes incubated with histamine and diphenhydramine produced LCF but neither LyMIF, whereas cells incubated with histamine in the presence of cimetidine produced both LyMIF but not LCF. These data suggest that a subset of lymphocytes defined by the presence of histamine-type 1 receptors are capable of producing two distinct species of lymphocyte migration inhibitory activity. These cells may contribute to the immobilization of effector T lymphocytes chemokinetically attracted to certain inflammatory sites.

Cell-mediated immune responses to artificial food additives in chronic urticaria.

In some cases of chronic urticaria it is suspected that food additives such as tartrazine and sodium benzoate or salicylates may play a role in the pathogenesis of the condition. Since, at times, chronic urticaria may appear histologically similar to a mild cell-mediated immune response, the release of the T cell-derived lymphokine leucocyte inhibitory factor (LIF), in response to incubation with these additives and with acetylsalicylic acid (ASA), was measured in vitro using cells from normal controls, from patients with chronic urticaria with or without clinically associated additive sensitivity and from patients with asthma with or without associated ASA sensitivity. It was found that significant production of LIF occurred in response to tartrazine and sodium benzoate in those individuals with chronic additive induced urticaria. In addition, tartrazine caused LIF release from mononuclear cells of ASA-sensitive asthmatics. These results may indicate a possible role for additive-induced cell-mediated immune responses in the pathogenesis of some cases of chronic urticaria and suggest a potential diagnostic test for this condition.