EOSINOPHILS AND ANTIGEN-ANTIBODY REACTIONS

Indigenous enteric eosinophils control DCs to initiate a primary Th2 immune response in vivo

Eosinophils natively inhabit the small intestine, but a functional role for them there has remained elusive. Here, we show that eosinophil-deficient mice were protected from induction of Th2-mediated peanut food allergy and anaphylaxis, and Th2 priming was restored by reconstitution with il4(+/+) or il4(-/-) eosinophils. Eosinophils controlled CD103(+) dendritic cell (DC) activation and migration from the intestine to draining lymph nodes, events necessary for Th2 priming. Eosinophil activation in vitro and in vivo led to degranulation of eosinophil peroxidase, a granule protein whose enzymatic activity promoted DC activation in mice and humans in vitro, and intestinal and extraintestinal mouse DC activation and mobilization to lymph nodes in vivo. Further, eosinophil peroxidase enhanced responses to ovalbumin seen after immunization. Thus, eosinophils can be critical contributors to the intestinal immune system, and granule-mediated shaping of DC responses can promote both intestinal and extraintestinal adaptive immunity.

Eosinophil-Cryptococcus neoformans interactions in vivo and in vitro

Eosinophils are components of inflammatory responses to a variety of pathogens. Although a variety of beneficial and harmful functions have been ascribed to these cells, their role in protection against infectious agents remains uncertain. Previous studies have reported eosinophilic pneumonia in mice infected intratracheally with Cryptococcus neoformans. We confirmed this observation and studied the inflammatory response in the lung at day 14 by light and electron microscopy. Immunostaining for glucuronoxylomannan showed isolated cryptococci inside the eosinophilic cuffs. Eosinophils were found to be in close association with C. neoformans in vivo. Cryptococci were associated with eosinophils within eosinophilic perivascular cuffs, within granulomas, and lining the alveolar space. To further investigate this phenomenon in vitro, we isolated rat peritoneal eosinophils and studied cryptococcus-eosinophil interactions in the presence and absence of anti-capsular immunoglobulin G1 (IgG1) and IgE monoclonal antibody (MAb). Eosinophils phagocytosed C. neoformans only in the presence of specific antibody. Phagocytosis was rapid, and dense rings that appeared to consist of granule contents were formed around the organisms. Mast cells were observed to occasionally phagocytose C. neoformans in vitro in the presence of IgE MAb. Our observations suggest that eosinophils may be effector cells against C. neoformans.

The importance of the eosinophil in head and neck cancer

In a previous study, we found tumor-associated tissue eosinophilia (TATE) to be a favorable prognostic indicator for squamous cell carcinoma of the head and neck (p less than 0.05). The present expanded study was undertaken to confirm this finding. The pathology of 120 head and neck tumors was examined for histologic features suggestive of poor prognosis. Ten descriptive histopathologic variables, including two malignancy grading scales, were correlated with DNA flow cytometric data and clinical outcome. No correlation was found between the malignancy grading scales and DNA flow cytometric data or clinical outcome. The present expanded study confirmed with greater statistical significance (p less than 0.001) that high-grade TATE is a favorable prognostic indicator for head and neck cancer. Furthermore, high-grade TATE was associated with the absence of distant metastasis (p less than 0.05). Using a stepwise logistic regression analysis of the clinicopathologic variables in the study, high-grade TATE was the most influential variable affecting clinical outcome, followed by border, stage, and perineural invasion. We conclude that the grade of TATE is a significant prognostic indicator for head and neck cancer. The significance and possible role of the eosinophil in the tumor-host interaction are discussed.

Live but not heat-killed mycobacteria cause rapid chemotaxis of large numbers of eosinophils in vivo and are ingested by the attracted granulocytes

We studied leukocyte chemotaxis triggered by a local injection of mycobacteria (Mycobacterium avium and M. smegmatis) in BALB/c and C57BL/6 mice. Our experimental model consisted of the induction of a subcutaneous air pouch in the dorsal area of mice and inoculation 6 days later of 10(8) CFU of myocobacteria. Inflammatory exudates were harvested from the air pouch cavities 15, 30, and 45 min after the injection of the inocula. Injection of the microorganisms resulted in the migration of an elevated number of eosinophilic granulocytes into the inflammatory cavities. At 30 min after the inoculation of the mycobacteria, the air pouches contained between (3.9 +/- 0.3) x 10(5) (M. avium) and (3.3 +/- 0.3) x 10(5) (M. smegmatis) eosinophils, corresponding to more than one-third (41.4 to 38.3%) of the leukocytes present in the inflammatory cavities. Less than one-half of the eosinophils were attracted to the air pouches when the same number of heat-killed mycobacteria were inoculated [(1.3 +/- 0.2) x 10(5) cells for M. avium and (1.5 +/- 0.2) x 10(5) cells for M. smegmatis]. Injection of gram-negative bacteria (Escherichia coli), of latex beads, or of casein resulted in the attraction of inflammatory eosinophils in numbers that were comparable to those attracted by the heat-killed mycobacteria. Our data document the fact that live mycobacteria exert a rapid chemotactic effect on eosinophils. We therefore postulate that mycobacteria either contain or induce the production of an eosinophilotactic factor. Because this chemotactic effect occurs during the acute inflammatory response to mycobacteria, it cannot be due to the formation of immune complexes (a major infection-associated chemotactic factor for eosinophils). The attracted eosinophils had an important role in the local phagocytosis of mycobacteria, as indicated by our finding, derived from thin-section electron microscopy quantifications, that at 30 min after M. avium inoculation the inflammatory exudates contained (2.2 +/- 0.5) x 10(5) mycobacterium-bearing eosinophils (corresponding to 57% of the total eosinophils), as compared with (2.1 +/- 0.1) x 10(5) neutrophils and (1.5 +/- 0.2) x 10(5) macrophages with ingested bacilli. We conclude that mycobacteria induce the attraction of eosinophils to inflammatory sites and that these granulocytes have the capacity to phagocytize these bacilli in situ.

Eosinophil chemotactic response to rat CGRP-1 is increased after exposure to trypsin or guinea-pig lung particulate fraction

Calcitonin Gene-Related Peptide (CGRP) immunoreactive nerve fibres innervate the vasculature and epithelia of the peripheral airways of the guinea-pig lung. Guinea-pig eosinophils exhibit a concentration-dependent chemotactic response to rat Calcitonin Gene-Related Peptide-1 (rCGRP-1). The sequence rCGRP-1-(32-35) (valyl-glycyl-seryl-glutamic acid), which is identical to an eosinophil chemotactic factor of anaphylaxis (ECF-A) previously purified from guinea-pig lung (Goetzl, E. J. and Austen, F. (1975) Proc. Natl. Acad. Sci. USA 72, 4123-4127), was both more potent and more effective than rCGRP-1 in the chemotaxis assay. Products of rCGRP-1 tryptic digestion exhibited increased chemotactic activity compared to the intact peptide. Exposure of rCGRP-1 to a particulate fraction of guinea-pig lung also elevated its chemotactic activity, increasing the resultant potency by one hundred-fold. Resolution of pure and digested peptides by reverse-phase h.p.l.c. revealed evidence of endopeptidase activity in the lung particulate fraction. Elution times of rCGRP-1 cleavage fragments differed mostly from those of tryptic digestion.

[Biochemistry of schistosomiasis mansoni. IV. Changes in the hepatic lysosome compartment in relation to the time of infection]

O Schistosoma mansoni e/ou seus ovos causam uma hepatopatia muito importante e com aspectos anátomo-clínicos bem característicos. Uma vez carregados pela corrente circulatória, os vermes podem ocluir ramos dicotômicos de maior calibre do sistema portal e, quando mortos produzem lesões às vezes extensas, primeiro necróticas, depois inflamatórias e, posteriormente cicatriciais, sempre circunscritas e não sistematizadas. Os ovos, além de penetrarem no's ramúsculos não dicotômicos da rede periductal, alcançam os ramos de distribuição ou até mesmo as vênulas aferentes, ocluin- do muitas delas e, como conseqüência, formam os granulomas intravasculares que podem levar a uma interrupção da corrente sangüínea portal a esse nível e alterações da circulação intralobular. A diminuição da taxa de oxigênio disponível e conseqüentemente o decréscimo do pH intra e extracelular são potentes labilizadores das membranas dos diversos componentes do compartimento lisossômico. A saída de hidrolases ácidas, proteínas catiônicas e hidrolases neutras, a partir desses orgãnulos, acarreta agressões tissulares muito importantes, com o desencadeamento e/ou manutenção dos processos inflamatórios típicos desta parasitose. Neste trabalho estudou-se as atividades lisossômicas ligadas às diversas fases da esquistossomose mansônica hepática. Os resultados indicaram que a integridade funcional dos complexos membranosos do compartimento lisossômico foi significativamente alterada, já a partir do segundo mês da infecção e que parece haver um estreito relacionamento entre o agravamento das lesões inflamatórias hepáticas com uma maior labilidade lisossômica.

Circulating immune complexes in eosinophilic fasciitis

Serum immune complexes were measured in 22 patients with eosinophilic fasciitis, 8 of whom had serial determinations. Elevated levels were found by Raji cell radioimmunoassay in 14 (64%) patients, by agarose gel electrophoresis in 13 (59%), and by C1q agglutination-inhibition in 9 (41%). Elevated levels by Raji cell assay were present more frequently at times of active disease [17 of 22 sera (77%)] than at times of inactive disease [2 of 24 (8%) (P less than 0.0005)] and were more closely correlated with disease activity than were eosinophilia, hypergammaglobulinemia, or increased erythrocyte sedimentation rate.

Carcinomas of the cervix with intense stromal eosinophilia

Stromal inflammatory reactions dominated by eosinophilic leukocytes have been reported in a small number of invasive cervical carcinomas. The clinicopathologic features of six patients whose cervical carcinomas were accompanied by an intense infiltrate of eosinophils were analyzed. Several patients also manifested an eosinophilia of peripheral blood and regional lymph nodes. The cervical carcinoma cells were regarded as the most likely cause of the tissue and blood eosinophilia since other etiologic factors were not identified. Eosinotactic and eosinopoietic substances probably either were produced directly by the carcinoma cells or resulted from immunologic interactions of inflammatory lymphoid cells and mast cells with antigens of the tumors. While stromal eosinophilia alone may not be of prognostic significance, eosinophilia of the peripheral blood may be an adverse sign in some patients with cervical carcinoma.

Carcinoma of the maxillary sinus with eosinophilia. Report of a case

A patient with carcinoma of the maxillary sinus presented with a blood eosinophilia and infiltration of eosinophilic leukocytes into the tumor tissue. Immediately after cancer therapy with intraarterial infusion of 5-fluorouracil into the superficial temporal artery, necrotomy and resection of the maxilla including radical neck dissection, the number of eosinophilic leukocytes was suddenly decreased and thereafter a transient increase in blood eosinophilic leukocyte count was observed. In this communication, a tentative mechanism for these events is suggested.

Immunofluorescence studies on eosinophilic granulocytes

Immunofluorescence techniques were used to find out whether immunoglobulins (Ig) and complement (C3) determinants are present on the membrane of eosinophilic granulocytes in atopic patients and in patients with an allergic contact dermatitis. Normal healthy individuals served as controls. The studies were performed with eosinophilic granulocytes in suspension and in thin cell layers. The demonstration of the presence of cytoplasmic Ig and C3 in eosinophilic granulocytes was carried out in skin specimens taken 20-30 min after injection of the antigen and in specimens taken from positive patch tests 48 h after application of the antigen. No immunoglobulins or C3 determinants could be demonstrated on the membrane of eosinophilic granulocytes in the patients or the healthy controls, when the suspension methods were used. However, in thin cell layers and in skin sections the eosinophilic granulocytes showed a positive fluorescence of the cytoplasm after having been exposed to various conjugates and a FITC solution. It is concluded that the commonly used immunofluorescence techniques tend to give non-specific staining results, most likely due to reactivity of the FITC marker of the conjugates with basic proteins present in the cytoplasm of the eosinophilic granulocyte.

Cortisol-induced migration of eosinophil leukocytes to lymphoid organs

Cortisol induces a migration of eosinophil leukocytes from the blood to several lymphoid organs, such as the spleen, lymph nodes and thymus, but not to other tissues. This migration explains the cortisol-induced blood eosinopenia, which is much more pronounced in intact than in splenectomized animals.

Hypercalcemic crisis associated with the hypereosinophilic syndrome

A patient with the idiopathic hyperosinophilic syndrome had severe, life-threatening hypercalcemia, a previously unreported complication of this unusual disease. Postmortem examination revelaed multiorgan eosinophilic infiltration and diffuse metastatic calcifications, but it did not disclose a definitive cause for the persistent hypercalcemia. It is concluded that the marked proliferation of eosinophils was the probable etiologic factor. Proposed mechanisms for this complication include (1) the destruction of bone by an expanding eosinophilic cell mass with subsequent calcium mobilization and (2) the production of a hypercalcemic humoral substance, possibly by the patient's eosinophils or as a consequence of their presence.

Localization of eosinophils in the thymus by the peroxidase reaction

Thymuses of human fetuses and infants and of young mice were investigated histochemically for peroxidase. Eosinophils were shown to be the only peroxidase-positive cells in the thymus. In human thymuses the eosinophilic cells were predominantly localized in medullar areas, with concentration of cell clusters at the cortico-medullar junction, around or inside Hassall's bodies and occasionally in high numbers in the intraseptal vessels of the cortex. In the normal mouse the eosinophils were evenly distributed throughout the medulla. Treatment with corticosteroids or X-rays produced a severe involution of the thymus with concommitant change in cellular pattern. The central areas of the thymus residue contained lymphocytes while the peripheral regions consisted of reticuloepithelia, macrophages and numerous eosinophils. Azathioprine did not change the morphology of the thymus. The numbers of eosinophils were slightly reduced, the distribution pattern remaining unchanged.

Antibody-dependent eosinophil-mediated damage to 51Cr-labeled schistosomula of Schistosoma mansoni: damage by purieid eosinophils

After earlier observations that antibody-dependent, cell-mediated damage to 51Cr-labeled schistosomula can be ablated by pretreatment of a mixed preparation of human peripheral blood leukocytes with an anti-eosinophil serum and complement, we investigated the cytotoxic effects of eosinophil-enriched cell preparations. Preparations containing up to 98.5% eosinophils and devoid of neutrophils were effective in mediating antibody-dependent damage to schistosomula. Preparations enriched in mononuclear cells or in neutrophils, and devoid of eosinophils, were inactive. Eosinophils from some patients with eosinophilia induced by schistosomiasis were less active on a cell-to-cell basis than cells from normal individuals. The possibility that such cells were initially blocked by immune complexes was considered, and it was found that reasonable cytotoxicity by purified eosinophils from patients with eosinophilia could be generated by overnight cultures. A possible requirement for cooperation between eosinophils and other cell types was also studied. Lymphocytes, neutrophils and monocytes failed to enhance eosinophil-mediated cytotoxicity. These results provide further evidence that the eosinophil is the only cell in man responsible for antibody-dependent, complement-independent damage to schistosomula in vitro. Eosinophils from individuals, however, differ in their cytotoxic potential by a mechanism yet to be elucidated. The possible relationship of these findings to immunity in vivo is discussed.

Cell mediated immunity and the inflammatory system

In this review we have considered the evidence for the existence of lymphokines and have focused on the specific mechanisms by which lymphokines modify the behavior of the various inflammatory cells. These mechanisms are based for the most part on in vitro observations. We have therefore discussed in detail data that document an in vivo role for various lymphokines. This evidence is based on experiments falling into two broad categories: the identification of lymphokines in tissue extracts and serum, and the demonstration of various biologic activities of exogenous lymphokines administered locally or systemically. The details of these kinds of experiments have been presented throughout the preceding discussion. The demonstration of lymphokines in vivo adds a new dimension to our ability to study human disease. The detection of migration inhibition factor in serum, for example, is technically simpler than studies of lymphocyte reactivity in patients with altered cellular immunity. Migration inhibition factor has already been found in the serum in several clinical settings, as described. The capacity of exogenous lymphokines for suppressing manifestations of delayed hypersensitivity may provide an explanation for the altered immunoreactivity often observed in some of those diseases. A final comment is in order regarding the significance of lymphokine production in the overall biologic scheme of things. In previous sections we noted that although activation of lymphocytes for lymphokine production by specific antigen is a property of T cells, B cells may be so activated nonspecifically by certain mitogens. Moreover, it has been shown that migration inhibition factor, or substances with similar biologic and physicochemical properties, may be found in certain replicating cultures of nonlymphoid cells. Also, we have recently shown that migration inhibitory activity, as well as certain other lymphokine-like activities such as macrophage and lymphocyte chemotaxis, may appear following the in vitro or in vivo infection of nonlymphoid as well as lymphoid cells by certain viruses. All these results suggest that lymphokine production, rather than "merely" representing an effector mechanism for cell mediated immunity and for certain kinds of helper functions in antibody synthesis, represents a general biologic phenomenon that may play a role in various aspects of host defense. Thus, such mediator substances should be more properly called "cytokines." Lymphokines represent a restricted set of cytokines made by one class of cells (lymphocytes) activated in certain unique ways. In this view the lmyphocyte has acquired some specialized means for triggering such production, not available to other cells.

Acute interstitial nephritis. A clinical and pathologic study based on renal biopsies

To define interstitial nephritis without preselection bias, 25 consecutive renal biopsy specimens from patients with tubular damage, interstitial damage and interstitial inflammation were analyzed in detail. In four patients (all with acute renal failure), tubulitis, and interstitial eosinophil and lymphocyte infiltration were found, but no glomerular abnormalities. In four others, the findings were similar but some glomerular abnormalities were noted. Two patients had probable healed interstitial nephritis. The clinical presentation varied from transient renal insufficincy to oliguric renal failure. Three of the patients with glomerular abnormalities had significant proteinuria. When the 10 patients with interstitial nephritis were compared with the other 15 serving as controls, striking features in the former group were skin rash, eosinophilia, the absence of hypertension and the frequency of administration of penicillin and its analogs. Serum immunoglobulin E (IgE) levels were elevated in three of the patients. The striking eosinophilia, interstitial eosinophil infiltration and increased IgE levels suggest that allergen-reaginic complexes may be involved in the pathogenesis of the lesion.

Bronchial carcinoma with eosinophilia and cardiomegaly

A patient with a giant cell carcinoma of the bronchus presented with headache and flushing attacks and a blood eosinophilia. He developed a right bundle branch block and later congestive cardiac failure. At post mortem he was found to have the appearance of Loeffler's endocarditis. A tentative mechanism for these events is proposed.

Behavior of eosinophil leukocytes in acute inflammation. II. Eosinophil dynamics during acute inflammation

The marked diminution in the number of circulating eosinophils, which has been shown to occur during acute bacterial infections, is a distinctive aspect of eosinophil physiology and of the host response to acute infection. The mouse rendered eosinophilic by infection with trichinosis provides a suitable model for study of the eosinopenic response induced by acute inflammation. The alterations in eosinophil dynamics associated with acute inflammatory reactions in trichinous mice were studied with pneumococcal abscesses, with Escherichia coli pyelonephritis, with Coxsackie viral pancreatitis, and with acute subcutaneous inflammation due to turpentine. Each of these stimuli of acute inflammation markedly suppressed the eosinophilia of trichinosis. This suggests that the eosinopenia is a response to the acute inflammatory process rather than the response to a specific type of pathogen. These studies apply quantitative techniques to ascertain the effects of acute inflammation on eosinophil production in bone marrow and on distribution of eosinophils in the peripheral tissues. From these observations, it is apparent that the initial response to acute inflammation includes a rapid drop in numbers of circulating eosinophils, a rapid accumulation of eosinophils at the periphery of the inflammatory site, and an inhibition of egress of eosinophils from the bone marrow. With prolongation of the inflammatory process, inhibition of eosinopoiesis occurs.

Disodium cromoglycate in the treatment of chronic proctitis

The effect of topical disodium cromoglycate (DSCG) has been examined in 30 patients with chronic active proctitis using a double-blind crossover trial. Each treatment period was four weeks and patients were given DSCG 200 mg by enema twice daily and 100 mg orally three times each day. Twenty-six patients completed the trial successfully, 14 responded to DSCG treatment, two improved with placebo, and 10 responded to neither. Patients who responded to DSCG had significantly more eosinophils in their rectal biopsies than those who failed to respond and in some instances the counts were very high. The findings support the hypothesis than an allergic reaction is important in the pathogenesis of proctitis.

In vitro and in vivo activity of a lymphocyte and immune complex-dependent chemotactic factor for eosinophils

When cultured in the presence of specific antigen, lymphocytes from delayed-hypersensitive guinea pigs release a number of biologically active substances into the culture medium. Such active supernatants can react with immune complexes in vitro to generate a factor which is chemotactic for eosinophils. The factor involved is unique, since previously described chemotactic factors for other cell types require for their generation either immune complexes or substances released into lymphocyte culture, but not both. In the case of the eosinophil chemotactic factor, the interaction between the substance elaborated by the lymphocytes and the immune complexes appears to be specific in that the immune complexes must contain the same antigen as that used to activate the lymphocyte cultures. Although this factor was generated in an in vitro system, it has been shown to possess in vivo as well as in vitro activity. It is therefore possible that this factor may be of biological significance in situations where eosinophils are participants in inflammatory or immunologic reactions.