Nasal lavage fluid concentrations of eotaxin-1 (CCL11) in naturally occurring allergic rhinitis: relationship to disease activity, nasal luminal eosinophil influx, and plasma protein exudation

BACKGROUND

Eotaxin-1 (CCL11) is a CC chemokine whose nasal eosinophilic chemotactic activity in vivo and in vitro has been demonstrated primarily using nasal allergen challenge models. The extension of these challenge findings to the in vivo setting has been limited.

OBJECTIVE

To obtain nasal lavage fluid from volunteers with perennial and seasonal (in- and out-of-season) allergic rhinitis (AR) and non-atopic non-rhinitic controls for the measurement of eotaxin-1 concentrations and to relate these findings to the symptomatic disease severity, the percentage of lavage eosinophils, and to alpha(2)-macroglobulin (alpha(2)-MG) lavage concentrations, as a marker of vascular permeability and an index of airway inflammation.

METHODS

Thirty-seven volunteers with AR (16 seasonal and 21 perennial) and 20 non-atopic non-rhinitic volunteers were recruited and phenotyped. Nasal lavage fluid was obtained by standardized protocol. The nasal lavage fluid concentrations of eotaxin and alpha(2)-MG were measured by ELISA, and differential cell counts performed on cytospins.

RESULTS

Eotaxin-1 nasal lavage fluid concentrations were significantly higher in both the perennial and seasonal (in-season) AR groups compared with the controls, and significantly related to the severity of symptom expression and to the percentage of lavage eosinophils. The lavage eosinophil counts were significantly higher in both the symptomatic rhinitis groups compared with the control groups and correlated with the lavage concentrations of alpha(2)-MG. alpha(2)-MG levels were significantly increased in seasonal (in-season) rhinitics compared with both non-atopic controls and seasonal (out-of-season) rhinitics. A significant correlation was observed between the levels of alpha(2)-MG and levels of eotaxin in the symptomatic allergic rhinitic groups.

CONCLUSIONS

This study clearly demonstrates the relevance of eotaxin-1 to the pathogenesis of naturally occurring AR.

Increased eosinophil-lineage committed progenitors in the lung of allergen-challenged mice

BACKGROUND

There is increasing evidence that hemopoietic progenitor cells may traffic from bone marrow to sites of allergen exposure in asthma and undergo in situ differentiation, contributing to ongoing airway inflammation. However, the isolation and detailed phenotyping of true CD34 + progenitors from lung tissue during an allergen-induced airway eosinophilia has not been performed.

OBJECTIVE

We attempted to isolate and investigate the in vivo kinetics of hemopoietic progenitor cells and production of eosinophilopoietic mediators in the lung.

METHODS

In a mouse model of allergic airway inflammation, cells were extracted from lung tissue by enzymatic digestion. Total (CD34 + 45 + ) and eosinophil lineage committed (CD34 + 45 + IL-5Ralpha + ) progenitors were enumerated by flow cytometry. Outcome measurements were made 2, 6, 12, 24, 48, and 72 hours and 7 and 14 days after allergen challenge.

RESULTS

Compared with saline control, CD34 + 45 + progenitors were elevated between 6 and 48 hours ( P < .05), attenuated by 72 hours and subsequently increased by 14 days ( P > .05). CD34 + 45 + IL-5Ralpha + progenitors were transiently elevated at 6 hours ( P < .05) before a return to preallergen levels by 12 hours and a subsequent increase at 14 days ( P < .05). Bronchoalveolar lavage eosinophils were increased at 2 hours, peaking at 72 hours ( P < .00625) and declining by 14 days. Both IL-5 and eotaxin levels were increased by 2 hours, peaking at 12 hours ( P < .05) and 24 hours ( P < .05), respectively.

CONCLUSION

We propose that the increase in CD34 + 45 + IL-5Ralpha + cells and the eosinophilopoietic mediators IL-5 and eotaxin in the lung after allergen exposure may promote in situ differentiation of eosinophils that contribute to ongoing allergic airway inflammation.

Lung eosinophilic inflammation and airway hyperreactivity are enhanced by murine anaphylactic, but not nonanaphylactic, IgG1 antibodies

BACKGROUND

Chronic airway inflammation is a fundamental feature of bronchial asthma, which is characterized by the accumulation and activation of inflammatory cells, such as mast cells and eosinophils, that are tightly regulated by TH2 cytokines and chemokines. Recently, we demonstrated, in a murine model of asthma with immunosuppressed mice reconstituted with antigen-specific IgE or IgG1 antibodies, that IgE, but not IgG1, participates in potentiation of airway inflammation and induction of airway hyperreactivity (AHR). The IgG1 antibody, however, did not elicit passive cutaneous anaphylactic reactions, which was in contrast to IgE.

OBJECTIVES

Because 2 types of murine IgG1 have been demonstrated with regard to anaphylactic activity, the present experiments were undertaken to determine the role of anaphylactic and nonanaphylactic IgG1 antibodies in the development of antigen-induced eosinophilia and AHR in this model.

METHODS

Dinitrophenyl-conjugated, heat-coagulated hen's egg white was implanted in immunosuppressed mice reconstituted with anaphylactic or nonanaphylactic IgG1. Intratracheal challenge with aggregated dinitrophenyl-ovalbumin was performed on day 14, and lung inflammatory and mechanical parameters were evaluated after 48 hours.

RESULTS

Our results demonstrated that reconstitution of immunosuppressed mice with anaphylactic IgG1 antibodies in contrast to nonanaphylactic IgG1 antibodies potentiates their ability to have pulmonary eosinophilic inflammation and AHR. IL-5 and eotaxin levels in bronchoalveolar lavage fluid from anaphylactic IgG1-reconstituted mice were also higher than those in nonanaphylactic IgG1-reconstituted mice.

CONCLUSIONS

These results indicate that the anaphylactic property of murine IgG1 molecules is essential for their capacity to enhance lung eosinophilic inflammation and to induce AHR.

Eotaxin level in induced sputum is increased in patients with bronchial asthma and in smokers

BACKGROUND

Airway eosinophilia is one of the hallmarks of asthma. Eotaxin may play an important role in eosinophil recruitment.

OBJECTIVES

To examine the relationship between eotaxin levels in the sputum and eosinophilic inflammation.

METHODS

The sputum was obtained from 11 non-smokers, 14 smokers and 13 asthmatic patients using a sputum induction method. Eotaxin and interleukin (IL)-5 levels in the sputum were determined by ELISA and immunocytochemical analysis.

RESULTS

Asthmatic patients had eosinophilia and smokers showed neutrophilia in their sputum. The eotaxin level in the sputum was significantly higher in smokers (median 412.5, range 91.1-872.2 pg/ml) and asthmatic patients (351.0, 185.0-928.0 pg/ml) compared with non-smokers (123.2, 0-369.0 pg/ml; both p < 0.05). IL-5 was detected in the sputum of 1 non-smoker, none of the smokers and 4 asthmatic patients. The percentage of eotaxin-positive cells was higher in smokers and asthmatic patients than in non-smokers, but the percentage of IL-5-positive cells was significantly higher only in asthmatic patients (p < 0.05).

CONCLUSIONS

These findings suggest that the elevated eotaxin level in the sputum does not always accompany the increase in eosinophils, and cooperation with another cytokine such as IL-5 may be required for the recruitment of eosinophils.

Eotaxin expression in oral squamous cell carcinomas with and without tumour associated tissue eosinophilia

AIM

Eotaxin is a powerful and selective eosinophil chemoattractant. The purpose of this study was to compare the expression of eotaxin in oral squamous cell carcinomas with and without tumour associated tissue eosinophilia (TATE). The mechanisms that control the recruitment of eosinophils to these tumours are not clearly established.

METHODS

A total of 60 patients with oral squamous cell carcinomas (OSCC) with TNM stages II and III, located in the tongue, oral floor, retromolar area and inferior gingiva were divided in two groups: 1--OSCC with intense eosinophilic inflammatory infiltrate and 2--OSCC with absent/low eosinophilic inflammatory infiltrate. The eotaxin expression was analyzed by immunohistochemistry using standard streptavidin-biotin-peroxidase complex technique with monoclonal (mouse anti-human eotaxin) and polyclonal (rabbit anti-human eotaxin) antibodies.

RESULTS

The eotaxin expression was identified in normal oral mucosa as well as in both OSCC groups including malignant epithelial cells, eosinophils, neutrophils, plasma cells and fibroblasts. The eosinophils showed intense immunopositivity for eotaxin.

CONCLUSION

These results suggest that the eotaxin expressed in oral squamous cell carcinomas, mainly derived from eosinophils, is probably involved in the mechanisms of eosinophils chemotaxis to the tumour and in the maintenance of TATE in these malignant tumours.

Pleural fluid levels of vascular cell adhesion molecule-1 are elevated in eosinophilic pleural effusions

STUDY OBJECTIVES

The mechanisms responsible for the accumulation of eosinophils in pleural fluid are not fully understood. The objective of the present study was to examine the relationship between pleural fluid eosinophilia and the levels of vascular cell adhesion molecule (VCAM)-1, eotaxin, RANTES (regulated upon activation, normal T-cell expressed and secreted), and interleukin (IL)-4 in pleural effusions.

PATIENTS AND METHODS

Thirty-one patients with eosinophilic pleural effusion (EPE) [eosinophil percentage > 10% of the pleural fluid nucleated cells] and 10 patients without EPE were evaluated. VCAM-1, eotaxin, RANTES, and IL-4 in all pleural fluids were measured using enzyme-linked immunosorbent assay kits. IL-5 levels of the same fluids were measured in a previous study.

RESULTS

VCAM-1, eotaxin, and RANTES but not IL-4 were detectable in the pleural fluids. The mean level of VCAM-1 in EPE (336 +/- 85 ng/mL) was significantly higher (p = 0.011) than that in the noneosinophilic effusions (260 +/- 34 ng/mL) [mean +/- SD]. VCAM-1 levels were significantly correlated with the eosinophil count and percentage in all pleural fluids (r = 0.43, p = 0.005, and r = 0.37, p = 0.019, respectively). Multiple linear regression analysis disclosed that both IL-5 (beta, 0.63; p < 0.001) and VCAM-1 (beta, 0.27, p = 0.025) are independent predictors of the number of eosinophils in all pleural fluids. RANTES and eotaxin did not differ significantly between EPEs and non-EPEs, and were not correlated with the number of pleural fluid eosinophils.

CONCLUSION

The levels of VCAM-1 are increased in EPE, suggesting that VCAM-1 is important in the pathogenesis of EPE. Neither eotaxin nor RANTES is associated with pleural fluid eosinophilia.

Up-regulation of cysteinyl leukotriene 1 receptor by IL-13 enables human lung fibroblasts to respond to leukotriene C4 and produce eotaxin

Cysteinyl leukotrienes (CysLTs) play an important role in eosinophilic airway inflammation. In addition to their direct chemotactic effects on eosinophils, indirect effects have been reported. Eotaxin is a potent eosinophil-specific chemotactic factor produced mainly by fibroblasts. We investigated whether CysLTs augment eosinophilic inflammation via eotaxin production by fibroblasts. Leukotriene (LT)C(4) alone had no effect on eotaxin production by human fetal lung fibroblasts (HFL-1). However, LTC(4) stimulated eotaxin production by IL-13-treated fibroblasts, thereby indirectly inducing eosinophil sequestration. Unstimulated fibroblasts did not respond to LTC(4), but coincubation or preincubation of fibroblasts with IL-13 altered the response to LTC(4). To examine the mechanism(s) involved, the expression of CysLT1R in HFL-1 was investigated by quantitative real-time PCR and flow cytometry. Only low levels of CysLT1R mRNA and no CysLT1R protein were expressed in unstimulated HFL-1. In contrast, stimulation with IL-13 at a concentration of 10 ng/ml for 24 h significantly up-regulated both CysLT1R mRNA and protein expression in HFL-1. The synergistic effect of LTC(4) and IL-13 on eotaxin production was abolished by CysLT1R antagonists pranlukast and montelukast. These findings suggest that IL-13 up-regulates CysLT1R expression, which may contribute to the synergistic effect of LTC(4) and IL-13 on eotaxin production by lung fibroblasts. In the Th2 cytokine-rich milieu, such as that in bronchial asthma, CysLT1R expression on fibroblasts might be up-regulated, thereby allowing CysLTs to act effectively and increase eosinophilic inflammation.

The kinetics of allergen-induced eotaxin level in nasal lavage fluid: its key role in eosinophil recruitment in nasal mucosa

Eotaxin (CCL11) is a potent eosinophil chemoattractant belonging to the C-C chemokine. To evaluate the role of eotaxin in eosinophilic inflammation in nasal mucosa, we investigated the levels of eosinophil chemoattractants in nasal lavage fluids obtained after antigen challenge, compared with eosinophil counts and eosinophil protein X (EPX) levels. In subjects with allergic rhinitis, allergen challenge led to parallel increases in eosinophil counts, levels of EPX, and eotaxin concentrations in nasal lavage fluid. The levels of eotaxin in lavage samples showed strong correlation with lavage levels of eosinophil counts and EPX. Normal subjects had few, if any, eosinophils and EPX as well as the measured parameters in their nasal lavage fluids before and after antigen challenge. In our experiments of eosinophil endothelial transmigration (TEM) assay using the nasal microvascular endothelial cells, eotaxin showed the most potent effect among various eosinophil chemoattractants. In addition, treatment of eosinophils with anti-CCR-3 mAb significantly blocked eosinophil TEM induced by homogenate of nasal mucosa. These results indicate that eotaxin has an important role in eosinophil-dependent inflammation in nasal mucosa and suggest that blocking eotaxin or CCR-3 might be useful for new therapeutic tools of allergic rhinitis.

Characterization of airway inflammation after repeated exposures to occupational agents

BACKGROUND

Little is known about the comparative kinetics of eosinophil recruitment after exposure to low- and high-molecular-weight sensitizers in subjects with occupational asthma (OA).

OBJECTIVES

The aims of the study were to investigate the kinetics of changes in inflammatory mediators associated with eosinophil infiltration (IL-5 and eotaxin) and to examine the nature of the airway inflammation induced in response to different types of occupational agents.

METHODS

We investigated 15 subjects with OA caused by high- and low-molecular-weight agents. The subjects were exposed to increasing doses of the relevant occupational agent over 3 to 4 days until a 20% fall in FEV(1) occurred. Methacholine challenge and sputum induction were performed at the end of each day of exposure. Sputum samples were assessed for differential cell counts, including eosinophils, IL-5, and eotaxin messenger RNA.

RESULTS

There was an increase in sputum eosinophils, eotaxin, and IL-5 on the day preceding the occurrence of asthmatic reaction, although there was no change in functional parameters (FEV(1) and PC(20)). Increase in sputum eosinophils was more prominent in subjects exposed to low-molecular-weight agents than to high-molecular-weight agents.

CONCLUSION

Changes in eosinophils, IL-5, and eotaxin precede functional changes after exposure to occupational agents in subjects with OA. Eosinophil inflammation is a feature of exposure to both high- and low-molecular-weight agents. Induced sputum may be a useful tool in the early diagnosis of OA.

Quantitative analysis of eotaxin and RANTES messenger RNA in nasal polyps: association of tissue and nasal eosinophils

OBJECTIVES/HYPOTHESIS

Nasal polyps develop in the ethmoidal and middle turbinate area, often in relation to inflammatory conditions. Their exact etiology and pathogenesis are still under debate. Histologically, the polyps are infiltrated by a number of inflammatory cells, with eosinophil predominating in most specimens. This finding suggests that the nasal polyp is an inflammatory growth that is controlled by the local environment. The chemokines eotaxin and RANTES (regulated on activation normal T cell expressed and secreted) have been postulated to be involved in the recruitment and activation of eosinophils to certain inflamed tissues. The purpose of this study was to investigate eotaxin and RANTES mRNA expression in nasal polyps and its effect on tissue and nasal eosinophils.

METHODS

Nasal polyps (917 allergic and 30 nonallergic cases) were obtained from endoscopic sinus surgery, and 15 normal inferior turbinates also were taken. Immunohistochemical staining for eosinophils and quantitative reverse transcriptase-polymerase chain reaction (RT-PCR) tests for eotaxin and RANTES mRNA expression were performed, and the concentration of nasal eosinophil cationic protein (ECP) was measured.

RESULTS

The amounts of eotaxin mRNA in the allergic nasal polyps were 11.4 times higher and the levels in the nonallergic polyps were 6.4 times higher than in the normal inferior turbinate. However, the RANTES mRNA expression did not show any differences among the three groups. Tissue eosinophilia and nasal ECP levels were significantly correlated with eotaxin mRNA level but not with RANTES mRNA expression.

CONCLUSION

Nasal polyp eosinophilic infiltration and activation correlate mainly with increased eotaxin gene expression rather than with RANTES expression.

Eotaxin levels in pleural effusions: comparison with monocyte chemoattractant protein-1 and IL-8

OBJECTIVE

In order to investigate the role of eotaxin in pleural diseases, we measured eotaxin in pleural effusions and studied the relationship between eotaxin levels and recruitment of inflammatory cells, particularly eosinophils. Interleukin-8 (IL-8) and monocyte chemoattractant protein-1 (MCP-1) levels were also measured for comparison.

METHODS

We evaluated 47 pleural effusion samples, 7 transudates and 40 exudates. The exudates consisted of 19 malignant, 11 tuberculous, and 5 parapneumonic effusions, and 5 effusions of other etiologies. Chemokine levels were measured by specific sandwich enzyme-linked immunosorbent assays.

RESULTS

Eotaxin was detected in all samples examined, but the levels did not differ significantly among the exudates. There was no significant correlation between the levels of eotaxin and MCP-1 or IL-8. The level of eotaxin but not the others was significantly higher in eosinophilic effusions (>10% eosinophils among white blood cells in the fluid) than in non-eosinophilic fluids. The number of eosinophils in pleural effusions was significantly correlated with the eotaxin levels, but not with the levels of other chemokines. The number of neutrophils was significantly correlated with IL-8 but not with the others.

CONCLUSIONS

Results suggest that eotaxin contributes to the migration of eosinophils in pleural inflammation. Taken together with the correlation between IL-8 and neutrophils, it appears that the predominant type of pleural inflammatory infiltrate is controlled, at least in part, by the subgroup of chemokines expressed in the pleural space.

Increased coexpression of eotaxin and interleukin 5 in bullous pemphigoid

While the presence of eosinophils in the skin lesions of bullous pemphigoid is well documented, the chemotactic factors responsible for eosinophil recruitment into the tissue still remain to be defined. In this study, eotaxin and interleukin-5 (IL-5) concentrations were determined in the blister fluid and sera of patients with bullous pemphigoid (acute and remission phase, n=6) in comparison with normal healthy controls (n=6) using the enzyme-linked immunosorbent assay (ELISA) technique. Eotaxin and IL-5 levels were increased in the blister fluid compared with the acute and remission phase sera, as well as compared with the sera of normal controls. In addition, immunoreactivity for eotaxin was predominantly found in the inflammatory cell infiltrate of lesional bullous pemphigoid biopsy specimens. In conclusion, the data provide evidence that co-operation of eotaxin and IL-5 may play an essential role in activating and recruiting eosinophils, which ultimately contribute to the tissue damage in bullous pemphigoid.

Eotaxin expression in Onchocerca volvulus-induced dermatitis after topical application of diethylcarbamazine

In persons with onchocerciasis, topical application of the anthelminthic diethylcarbamazine (DEC) induces clinical and histologic responses similar to acute papular onchodermatitis, including recruitment of eosinophils to the skin. To determine whether the eosinophil chemokine eotaxin is likely to be associated with eosinophil recruitment in onchodermatitis, DEC was applied to a 5-cm2 area on the skin of infected persons, and biopsies were taken from lesions 24 h later. Histologic analysis showed elevated dermal and epidermal eosinophils compared with tissue from an adjacent (untreated) site. Reverse transcription-polymerase chain reaction showed that eotaxin gene expression in DEC-treated skin was elevated 2- to 17-fold compared with control tissue. Eotaxin immunoreactivity was noted in mononuclear cells and eosinophils in the perivascular region of the dermis and in lymphatic and vascular endothelial cells. Together, these observations are consistent with a role for eotaxin in recruitment of eosinophils to the dermis in early stage onchocercal skin disease.

Dermal fibroblasts represent a potent major source of human eotaxin: In vitro production and cytokine-mediated regulation

Accumulating evidence indicates that eotaxin plays an integral role in tissue recruitment of eosinophils in humans as well as in animals. To clarify which types of cells are actually important as sources of human eotaxin, we used a specific enzyme-linked immunosorbent assay (ELISA) to compare various types of hemopoietic and nonhemopoietic cells for the ability to produce eotaxin protein. Regardless of various conditioning, we failed to determine any significant eotaxin generation by peripheral leukocytes and vein endothelial cells (less than 20 pg/ml). A small amount of immunoreactive eotaxin was detected in cultures of A549 bronchial epithelial cell line cells. In contrast, dermal fibroblasts were capable of generating extremely high, and potentially biologically relevant, amounts of eotaxin protein (on the order of ng/ml). The eotaxin generation was induced by tumour necrosis factor alpha (TNF-alpha) or IL-4, and the production was drastically increased by combined use of these cytokines. Because fibroblasts are ideally situated within the interstium at the sites of allergic responses, our finding that these cells represent an important cellular source of eotaxin suggests that fibroblast-derived eotaxin may act to regulate eosinophil recruitment in a paracrine fashion.

Eotaxin contributes to renal interstitial eosinophilia

BACKGROUND

A potent eosinophil chemotactic cytokine, human eotaxin, is directly chemotactic for eosinophils. Therefore, the specific expression of eotaxin in tissue might play a crucial role in tissue eosinophilia. However, the precise molecular mechanism of the recruitment and activation of eosinophils in human renal diseases remains to be investigated. We evaluated the role of eotaxin in the pathogenesis of human diffuse interstitial nephritis with marked infiltration of eosinophils.

METHODS

In this study, we examined 20 healthy volunteers. 56 patients with primary or secondary glomerular diseases and two hypereosinophilic syndrome patients without renal involvement. Urinary and serum eotaxin levels were determined by an enzyme-linked immunosorbent assay. We also detected the presence of eotaxin protein immunohistochemically.

RESULTS

On the one hand, urinary levels of eotaxin were significantly higher before the initiation of glucocorticoid administration in the patient with interstitial nephritis with marked infiltration of eosinophils. On the other hand, urinary eotaxin levels were not detected in any patients with nephrotic syndrome, interstitial nephritis without eosinophils, hypereosinophilic syndrome without renal involvement or other renal diseases. Serum eotaxin levels were not detected in any of the patients. Therefore, the detection of eotaxin in the urine was specific for renal interstitial eosinophilia. Moreover, endothelial cells, infiltrating mononuclear cells and renal epithelial cells in the tubulointerstitial lesions were immunostained with specific anti-eotaxin antibodies. Furthermore, the elevated urinary levels of eotaxin decreased dramatically during glucocorticoid-induced convalescence.

HYPOTHESIS

We hypothesize that in situ expression of eotaxin may provide a new mechanism to explain the renal interstitial eosinophil infiltration.

Eosinophil chemotactic factors from cysticercoids of Hymenolepis nana

A comparative study of eosinophil chemotactic factors was carried out using cysticercoids and oncospheres of Hymenolepis nana. Cysticercoids showed twice the chemotactic activity for eosinophils than the oncospheres. Eosinophilia induced by oncospheres and cysticercoids observed in secondary and primary infections, respectively, were discussed from the view point of the immunobiology of this parasite.

[Lymphocyte chemotactic factor in tuberculous pleural effusion]

To evaluate whether lymphocyte chemotactic factor is involved in the accumulation of lymphocytes in tuberculous pleurisy, we measured lymphocyte chemotactic activity in tuberculous pleural effusions, and compared with that in malignant pleural effusions and transudate. The lymphocyte chemotactic activity was measured in vitro with chemotactic chamber. The cells suspended in the culture medium was added to the upper well and the effusions, normal human serum (NHS), or culture medium were placed below nitrocellulose filter. The lymphocyte migration was quantified by counting the number of cells migrating beyond a distance of 70 microns from top of the filter in 5 selected fields. The chemotactic activity of the effusions was expressed as a percentage of the control migration in the culture medium. When we used the freshly isolated peripheral blood lymphocytes as responding cells, the chemotactic activity was 176.0 +/- 41.3% in tuberculous effusions, 115.1 +/- 53.8% in malignant effusions, 87.1 +/- 16.1% in transudate, and 113.3 +/- 24.2% in NHS, respectively. The activity of tuberculous effusions was significantly higher than that of transudate and NHS. When we used PHA-activated lymphocytes, the activity was 284.4 +/- 159.3% in tuberculous effusions, 123.1 +/- 77.6% in malignant effusions, 75.8 +/- 10.3% in transudate, and 52.6 +/- 10.1% in NHS, respectively. The activity of tuberculous effusions was significantly higher than that of malignant effusions, transudate and NHS. The chemotactic activity of tuberculous effusions to PHA-activated lymphocytes was significantly higher than that to freshly isolated lymphocytes. The activity was specific for T lymphocytes, and showed both chemotaxis and chemokinesis by checkerboard analysis. Gel filtration performed with Sephacryl S-200 revealed that the chemotactic activities in a tuberculous fluid had three peaks located in the regions between blue dextran and immunoglobulin G, near to human albumin and cytochrome c marker. The most potent activity was found at the region near human albumin. Lymphocyte chemotactic factor in tuberculous effusion may stimulate the migration of T lymphocytes, especially the activated T lymphocytes to the pleural spaces.

Cell infiltration, ICAM-1 expression, and eosinophil chemotactic activity in asthmatic sputum

We have applied the technique of sputum induction by hypertonic saline in asthmatics and nonatopic control subjects to study an array of indices of airway inflammation believed to be relevant to asthma pathogenesis. Compatible with a central role for eosinophils and mast cells in asthma, sputum of asthmatic subjects contained increased numbers of eosinophils and levels of eosinophil cationic protein (ECP) and mast cell tryptase. Eosinophil numbers, and ECP and histamine levels correlated with the degree of methacholine airways responsiveness, and ECP, tryptase, and histamine correlated with raised concentrations of albumin. Using the micro-Boyden chamber technique eosinophil chemotactic activity was identified only in the sputum from asthmatics. The correlation between the raised levels of total IgA, IL-8/IgA complexes, and tryptase and the degree of sputum eosinophilia and ECP levels, suggests possible mechanisms for eosinophil chemotaxis and activation in asthma. Row cytometric analysis of sputum lymphocytes showed an increase in CD4+ T cells and T cells expressing intercellular adhesion molecule-1 (ICAM-1) in asthma which, together with the finding of raised levels of soluble ICAM-1 in the sputum, indicates upregulation of this adhesion molecule. Finally, the proportion of CD16+ natural killer (NK) cells was reduced in the sputum of asthmatics. These observations highlight the importance of the airway inflammation in causing asthma and further confirm the usefulness of sputum induction as a tool in asthma research.

Eosinophil recruitment following allergen challenge is associated with the release of the chemokine RANTES into asthmatic airways

Eosinophil infiltration of the airways in response to allergen exposure is a characteristic of bronchial asthma. However, the mechanisms by which these cells are recruited are poorly understood. We have investigated the presence of eosinophil chemotactic activity (ECA) in bronchoalveolar lavage fluid obtained from allergic asthmatics (n = 6) 4 h after endobronchial allergen challenge. ECA was purified by sequential heparin affinity chromatography and reverse-phase HPLC. A single peak of ECA was detected; SDS-PAGE and Western blot analysis showed that the peak contained a protein of 8 kDa and corresponded to the chemokine RANTES (regulated upon activation, normal T cell expressed and secreted). Consistent with this, the ECA was neutralized by an Ab to RANTES. Measurement of RANTES by ELISA in 10x concentrated bronchoalveolar lavage fluid showed increased levels of this chemokine at the allergen site (median, 187 pg/ml; range, 46-263 pg/ml) in comparison with a saline challenge control site (median, 32.5 pg/ml; range, 11-94 pg/ml), P < 0.005. Furthermore, there was a significant correlation between concentrations of immunoreactive RANTES and the number of eosinophils at the allergen challenge site (r = 0.8; p < 0.001), but not at the saline site (r = 0.2; p = 0.12). These results suggest that RANTES in involved in the recruitment of eosinophils into the asthmatic airways after allergen challenge.

IL-5 accounts for the mouse pleural eosinophil accumulation triggered by antigen but not by LPS

The involvement of interleukin-5 (IL-5) in the pleural eosinophilia induced by LPS or allergen was investigated. The number of pleural eosinophils in actively sensitized mice increased 24 h after the intrathoracic (i.t.) injection of ovalbumin (12 mg/cavity), peaked within 72 h, and persisted significantly increased for at least 120 h. Despite being less intense, the i.t. injection of LPS (250 ng/cavity) also increased the number of pleural eosinophils at 24 h, returning to basal levels within 72 h. Intraperitoneal pretreatment with monoclonal antibody to IL-5 (TRFK-4 and TRFK-5, 500 mg/kg) suppressed the eosinophil accumulation induced by IL-5 (200 units/cavity) or ovalbumin, but had no effect on the LPS-induced eosinophilia. Transfer of the cell-free pleural washing from LPS-treated donor mice to naive recipient animals led to a selective increase in the eosinophil counts. The co-incubation of the pleural washing from LPS-treated animals with monoclonal antibody to IL-5 failed to modify the phenomenon. The results indicate that IL-5 plays an important role in the antigen-induced accumulation of eosinophils in vivo, but not in the eosinophilia triggered by LPS.

Markers for eosinophils and T-lymphocytes as predictors of late asthmatic response

Bronchial allergen challenge was performed on 12 allergic asthmatics during a stable phase of their disease. After resolution of the immediate bronchial response, fractional lung lavage was performed twice, two and 24 h post-challenge. The recovery of eosinophils, eosinophil cationic protein (ECP), eosinophil chemotactic activity (ECA) and immunohistochemical staining of the phenotypically distinct population stainable by the monoclonal antibody CD45RO, agreed to indicate T-memory cells, were assessed in the two lavages. Serial measurements of lung function, and serum concentration of ECP were also done. We found that although the recoveries in bronchial washes of eosinophil cells and ECP tended to increase during the trial, none of these variables predicted the emergence of late phase bronchial response (LPR). Instead, the proportion in the 2-h lavages, of memory-cells or ECA predicted the LPR. These two variables were inversely correlated to each other in the first lavage, suggesting the T-cells to be potential major sources of ECA. The fact that T-cells and ECA, but not markers for eosinophil activation in lavage, predicted the LPR, may suggest T-cell activation to precede the activation of the eosinophils within the lung after a bronchial allergen challenge. There was a close correlation between LPR and serum concentration of ECP obtained at the end of the trial, 24 h post-challenge, suggesting either a delayed or a continuous activation of circulating eosinophils after bronchial allergen challenge.

Blood eosinophil numbers and activity during 24 hours: effects of treatment with budesonide and bambuterol

The effects of the inhaled corticosteroid budesonide and the oral long-acting beta-agonist bambuterol on circadian variation of blood eosinophil numbers, serum levels of eosinophil cationic protein (ECP), serum eosinophil chemotactic activity (ECA), and serum neutrophil chemotactic activity (NCA) were studied in two groups of patients with allergic asthma. Group 1 (n = 8) had a circadian variation of peak expiratory flow (PEF) 15% or greater, and group 2 (n = 9) had a circadian PEF variation less than 15%. Both groups were randomized and crossover treated for 4 weeks with (A) 0.4 mg budesonide at 8 AM and 8 PM, (B) 20 mg bambuterol at 8 PM, and (C) placebo. At the end of each period blood eosinophil numbers, ECP, ECA, and NCA were measured during 24 hours at 4-hour intervals. No significant differences in the inflammatory parameters could be observed between the groups, although eosinophil numbers tended to be higher in group 1 than in group 2. Highest eosinophil numbers were observed at night. Budesonide reduced both eosinophil numbers and ECP levels, especially at night; bambuterol had no effect on both variables. No circadian variation or treatment effects were observed for ECA and NCA. This study suggests a role for the eosinophil in the nocturnal worsening of asthma, and it demonstrates that budesonide produces, in contrast to bambuterol, a reduction of (nocturnal) eosinophil numbers and activity.

The effect of immunotherapy on eosinophil accumulation and production of eosinophil chemotactic activity in the lung of subjects with asthma during natural pollen exposure

Two groups of birch pollen--allergic patients with seasonal rhinoconjunctivitis and asthma were followed during two consecutive birch-pollen seasons, one group, N = 10, during a season with high pollen load, and one group, N = 15, during a season of low pollen load. Half the patients were treated with immunotherapy (IT) for 3 and 4 years, respectively. The other half of the patients served as control group (non-IT). Bronchoalveolar lavage (BAL) was performed once before each season and once during the pollen season. Eosinophil (EOS) numbers in BAL were increased (p less than 0.01) during the season with high pollen load but not in the season with a low pollen load, and this increment was absent in the IT-treated group. Also, the EOS cationic protein levels were raised in the non-IT-treated group during the season with a high pollen load. The levels of EOS and neutrophil chemotactic activity were raised in BAL in both seasons in the non-IT-treated group compared with the IT-treated group (p less than 0.02, p less than 0.003, p less than 0.04, and p less than 0.005 in high- and low-load pollen season, respectively). Serum and BAL eosinophil chemotactic activity (ECA) were positively correlated (p less than 0.001). We conclude that there is an influx of active EOSs into the lung of pollen-allergic patients with asthma during a pollen season, which may be abrogated by IT. Furthermore, the generation of ECA appears to be an extremely sensitive marker of antigenic exposure, and the potent inhibition of the generation of ECA by IT may provide a clue as to the mechanism of this treatment.

Functional heterogeneity of human eosinophil chemotactic lymphokines

We have previously isolated two OKT4-positive T lymphocyte-derived eosinophil chemotactic factors (LDECF) with MW of about 45-60 kDa of which production is different in antigen or mitogen dependency (1-4). The production of a LDECF from patients with parasite disease (LDECF-PD) is dependent on antigen or mitogen stimulation, whereas another LDECF from patients with hypereosinophilic syndrome (HES) is independent. Further purification of these LDECF with isoelectric focusing reveals that an isoelectric point of LDECF-HES is about 6.0 and that of LDECF-PD is around 7.0 to 8.0. Little or no activity of partially purified LDECF-HES and LDECF-PD is suppressed by treatment with monoclonal antibodies against GM-CSM, IL-3, and IL-5, which activate eosinophils. LDECF-HES and LDECF-PD attract eosinophils from healthy individuals. In contrast, eosinophils from patients with HES are attracted by LDECF-HES but not LDECF-PD. LDECF-HES enhances the expression of Fc epsilon receptor II (Fc epsilon RII) and Fc gamma receptor III (Fc gamma RIII) but not that of CR1 on eosinophils, whereas LDECF-PD enhances their CR1 and Fc gamma RIII expression but not Fc epsilon RII expression. Moreover, treatment with LDECF-PD suppresses the release of eosinophilic cationic protein (ECP) from eosinophils, whereas that with LDECF-HES fails. Treatment of eosinophils with phorbol myristate acetate enhances ECP release from eosinophils but it fails to enhance the intracellular ECP level. However, the intracellular ECP level is elevated by stimulation with phorbol myristate acetate if eosinophils were previously treated with LDECF-HES but not with LDECF-PD. These results suggest that various kinds of LDECF are produced according to the nature of diseases, and that each LDECF has functional heterogeneity on eosinophils.

Neutrophil chemotactic activity in toluene diisocyanate (TDI)-induced asthma

We quantitated serum neutrophil chemotactic activity (NCA), which is associated with mast cell or basophil activation, to determine if mast cell or basophil mediators are released during bronchoprovocation-inhalation challenge with subirritant levels of toluene diisocyanate (TDI). Four subjects with suspected TDI-induced asthma and four mite-sensitive subjects with asthma who served as a comparison group were studied. NCA was measured in a multiwell, microchemotaxis chamber. Blood samples were collected, and FEV1 measurements were performed before challenge and at regular intervals during the subsequent 24 hours. Three of four workers clinically sensitive to TDI reacted to a subirritant TDI exposure. There was no increase in NCA during placebo challenges. NCA increased in the three TDI-sensitive workers during early and late asthmatic reactions in quantities proportional to the FEV1 decline. No increase in NCA was found during TDI exposures in the TDI-negative worker. Gel filtration analysis demonstrated the main NCA fraction eluted with macromolecules of an estimated molecular weight greater than 440,000 daltons. This characteristic is compatible with neutrophil chemotactic factor of basophil or mast cell origin. The kinetics of NCA release were similar in mite- and TDI-induced asthmatic reactions. A high correlation (r = 0.97; p = 0.0006) was obtained between the percent decrease in FEV1 during early asthmatic reactions and percent increase in NCA. These observations support the hypothesis that activation of mast cells or basophils is associated with TDI-induced early and late asthmatic reaction.

Visualization of eosinophil chemotactic factor in abomasal tissue of cattle by immunoperoxidase staining during Ostertagia ostertagi infection

Eosinophil chemotactic factor (ECF) was localized predominantly in the intestinal cells and lateral hypodermal cords of developing fifth stage larvae (L5) of Ostertagia ostertagi within abomasal tissue cross-sections by peroxidase in an antibody sandwich technique using monoclonal antibody to ECF. Cooperia oncophora larvae in tissue cross-sections did not stain using this technique. These experiments demonstrate that ECF is localized in Ostertagia ostertagi organelles and is probably released by the developing L5 into the abomasal tissue surrounding the parasitized gland. The presence of ECF within O. ostertagi larvae in situ and the results of previous experiments demonstrated in vitro and in vivo ECF chemotactic activity help to explain why eosinophils are observed histologically in abomasal tissues from cattle with ostertagiasis.

Leukocyte accumulation in sparganosis: further characterization of an eosinophil chemotactic factor of the plerocercoid of Spirometra erinacei

An eosinophil chemotactic (ECF) was partially purified from plerocercoids of Spirometra erinacei by a combination of anion-exchange chromatography on DE52 and gel filtration on Sephacryl S-200. The molecular weight of ECF was estimated to be 25,000-45,000 by high-pressure liquid chromatography. The ECF was bound with concanavalin A-Sepharose. The ECF was sensitive to periodate oxidation and to heating (56 degrees C, 30 min). On isoelectric focusing, eosinophil chemotactic activity was clearly revealed at pI 4.1. These results suggest that ECF of S. erinacei plerocercoid is an acidic glycoprotein. An intradermal injection of ECF eosinophil attractions in the normal guinea pig skin.

Eosinophil chemotactic factor in tumour tissue from a patient with Kimura's disease

An extract of tumour tissue from a patient with Kimura's disease was tested for eosinophil chemotactic activity using the Boyden chamber method. Eosinophil chemotactic activity was detected in the tissue extract, and after gel filtration maximum activity was found in the fraction with a molecular weight of approximately 1000 daltons. This factor may play a role in the tissue eosinophilia which occurs in Kimura's disease.

Incontinentia pigmenti: eosinophil chemotactic activity of the crusted scales in the vesiculobullous stage

To investigate the mechanisms underlying eosinophil infiltration into the epidermis in incontinentia pigmenti (IP), we studied the eosinophil chemotactic activity in extracts of the crusted scales from three patients with IP in the vesiculobullous stage. Eosinophil chemotactic activity was detected in the eluates from a Sephadex G-75 chromatography column between the vitamin B12 and phenol red markers. The chemotactic activity was heat-stable and resistant to enzyme digestion, and recovered after ether extraction at low pH. Leukotriene B4 (LTB4) was demonstrated in the fractions with high eosinophil chemotactic activity. These findings suggest that LTB4 plays an important role in the accumulation of eosinophils within the epidermis in IP, in the vesiculobullous stage. Blood eosinophilia, however, may not be induced by the eosinophil chemotactic factors in the scales.

Isolation and partial characterization of an eosinophil chemotactic factor from metacestodes of Taenia taeniaeformis (ECF-Tt)

Eosinophil chemotactic activity associated with protein extracts of Taenia taeniaeformis metacestodes was investigated. Chemotactic activity was associated with the nonbound protein after QAE cellulose chromatography of a 3 M KCl extract of homogenized larvae. When this material was precipitated with ammonium sulfate, activity was present in the 40 to 80% precipitate. Upon rechromatography on QAE cellulose equilibrated in a low ionic strength buffer, eosinophil chemotactic activity was retained by the gel and eluted after application of the NaCl gradient. Gel filtration of Sephacryl S-300 yielded an estimated m.w. of 91,000. Chromatofocusing revealed a broad peak of activity with a pI of 4.5 to 5.0. SDS-PAGE showed the active fraction migrated as a protein with a m.w. of 10,400. ECF-Tt had chemotactic and chemokinetic activity for equine eosinophils and murine eosinophils, but not for equine and murine neutrophils.

Eosinophilic pustular folliculitis. Studies on possible chemotactic factors involved in the formation of pustules

Eosinophilic pustular folliculitis (EPF) is a dermatosis of unknown aetiology, characterized by repeated development of pruritic follicular papulopustules with a tendency to form an annular configuration on the face and other seborrhoeic areas, and by palmoplantar pustular lesions in one-fifth of the patients. Both types of lesions are infiltrated mainly by eosinophils with some polymorphonuclear leukocytes (PMN). To elucidate the mechanisms underlying pustule formation, we studied the chemotactic activity for leukocytes of the skin surface lipids (SSL) obtained from seborrhoeic areas. No specific chemotactic activity was detectable in stored SSL from patients with EPF. However, fresh SSL collected from the seborrhoeic areas of normal adults contained chemotactic substances for eosinophils and PMN which were labile on storage in air. In stratum corneum extracts from palmoplantar lesions of patients with EPF we demonstrated the presence of a 13000 molecular weight chemoattractant factor for PMN, the activity of which was partially inhibited by antiserum against C5a, and a low molecular weight lipid-soluble chemotactic factor for eosinophils, the activity of which was also lost on storage in air. Our findings suggest that these chemotactic factors play a role in the production of the characteristic pustular lesions of EPF.

Partial purification and characterization of eosinophil chemotactic factors from soluble extract of Fasciola species

Eosinophil chemotactic factor (ECF) was partially purified from common liver flukes (Japanese strain of Fasciola sp) by a combination of anion-exchange chromatography on DE52 and gel filtration on Sephacryl S-200. The molecular weight of ECF was estimated to be approximately 27,000 by high-pressure liquid chromatography. The ECF was heat labile (56 and 100 C for 30 minutes) and was not bound with lentil-lectin Sepharose. The results of isoelectric focusing showed that ECF comprises at least 2 components; one was a major ECF with an isoelectric point of 3.1, and the other, a minor ECF with an isoelectric point of 3.8 to 4.5. These results indicate that ECF of common liver flukes are acidic proteins.

Conformation of the eosinophil chemotactic tetrapeptides and analogues in dimethyl sulfoxide. 1H n.m.r. studies

Proton nuclear magnetic resonance parameters are reported for DMSO-d6 solutions of the eosinophil chemotactic tetrapeptides, Val1-Gly2-Ser3-Glu4 and Ala1-Gly2-Ser3-Glu4, as well as three analogues of the Val1 tetrapeptide, D-Val1, Ala2 and Ala3. The synthesis of Val-(S)-[alpha-2 H1] Gly-Ala-Glu, in which the glycine has been stereospecifically deuterated in the H alpha 3 position, has allowed the assignment of the 1H resonances belonging to individual H alpha 2 and H alpha 3 glycine methylene protons. Simulation of the glycine ABX spin system yields two vicinal coupling constants which are consistent with a highly preferred conformation about the glycine HN-C alpha bond. The chemical shifts, coupling constants, temperature coefficients of amide proton chemical shifts and calculated side chain rotamer populations are reported for all peptides. The coupling constant analysis and temperature coefficients of amide proton chemical shifts together suggest that a type I beta-turn conformation is preferred by the Ala3 analogue. The 1H n.m.r. parameters of the other peptides suggest that these can also adopt a beta-turn conformation in DMSO. There are, however, considerable differences in the extent of conformational averaging undergone by the various peptides.

Eosinophil and neutrophil chemotactic activities of adult worm extracts of Schistosoma japonicum in vivo and in vitro

Large numbers of eosinophils and neutrophils attracted to the soluble extract of Schistosoma japonicum adult worms (SjAW-ext) were detected at the injection site of normal guinea pig skin. Eosinophil and neutrophil chemotactic activities were also confirmed in in vitro assay by using blind-well chambers with Millipore filters in dose-dependent fashion. Two components of SjAW-ext showed eosinophil chemotactic activity; one was in the high molecular weight fraction (JAE-H), estimated to be more than 440,000 daltons, the other in the low molecular weight fraction (JAE-L) obtained by Sephadex G-200 gel filtration. High neutrophil chemotactic activity was detected in the JAE-L. These eosinophil and neutrophil chemotactic activities were also detected in culture fluid of S. japonicum adult worms. Eosinophil chemotactic factor (ECF) of JAE-H was stable to heating (100 C, 30 min) and pronase digestion, but completely destroyed by periodate oxidation. It is suggested that the ECF of JAE-H is a glycoprotein. JAE-L was also stable to heating (56 and 100 C, 30 min) and pronase digestion for eosinophil chemotaxis. Possible roles of those activities in schistosome infections are discussed.

Large cell carcinoma of the lung associated with marked eosinophilia. A case report

A case of large cell carcinoma of the lung which produced eosinophil colony stimulating factor and eosinophil chemotactic factor was reported. A 52-year-old Japanese man with a tumor in the left upper lobe of the lung underwent left pneumonectomy. Marked eosinophilia persisted especially after recurrence, with a maximum peripheral leukocyte count of 161,000/mm3, of which 78% consisted of eosinophils. The patient died of pulmonary insufficiency 18 months after surgery. At autopsy, metastatic tumor tissues and almost all organs were markedly infiltrated with eosinophils, especially the spleen, and there was marked proliferation of eosinophils in the bone marrow. Eosinophil colony stimulating factor production by the transplanted tumor in a nude mouse was confirmed by use of a human bone marrow culture assay system. Eosinophil chemotactic factor production by metastatic tumor tissue also was proved by a modified micro-filter technique.

The regulation of tissue eosinophil chemotactic factor and inhibitor in allergic skin lesions of Freund's complete adjuvant-treated guinea-pigs

The regulation of tissue eosinophilia induced by dinitrophenyl-ascaris extract (DNP-As) was investigated in guinea-pigs. Biphasic tissue eosinophilia peaking at 6 and 24 hr was observed in the skin lesions in Bordetella pertussis vaccine (Bp)-treated animals. In contrast, only the early phase of tissue eosinophilia was observed in Freund's complete adjuvant (FCA)-treated animals. Although less eosinophil chemotactic activity was detected in 24-hr-old skin extract of FCA-treated animals (FCA-extract), evident activity was recovered in the concanavalin A eluate (Con A-eluate) when FCA-extract was fractionated by Con A Sepharose. The chemotactic factor in Con A-eluate of FCA-extract was confirmed to be the T cell-derived eosinophil chemotactic factor, termed Delayed ECF-a, which has been isolated from allergic skin lesions by immunoadsorption. Another factor from the same skin lesions, Delayed ECF-b (which is a serum-derived one), was not detected in the FCA-extract. When eosinophils were mixed or pretreated with Con A-effluent of FCA-extract, the treated cells failed to be attracted by Delayed ECF-a, while the response to Delayed ECF-b was not affected, indicating that the inhibition was selective for Delayed ECF-a but not for Delayed ECF-b, and the eosinophil chemotactic inhibitory factor (ECIF) acts on eosinophils directly. Major ECIF activity was associated with a mol. wt. of 70,000 and minor with 12,500. Furthermore, the activity was absorbed by eosinophils but not by macrophages suggesting that eosinophils have receptor sites for ECIF. It was thus suggested that the appearance of ECIF, which is selective for the response of eosinophils to Delayed ECF-a, and decreased Delayed ECF-b production resulted in the inhibition of delayed tissue eosinophilia in FCA-treated guinea-pigs.

The mediation of tissue eosinophilia in hypersensitivity reactions. V. Comparative study of tissue eosinophilia in the skin lesions of local and systemic passive cutaneous anaphylactic reactions

Tissue eosinophilia in active cutaneous anaphylaxis reactions is biphasic: the early phase (6 hr) is induced by a low molecular (mol. wt. 300) factor (early ECF), and the delayed phase (24 hr) is mediated by synergy of two different factors (delayed ECF-a and -b). In this study, we report the mediation of tissue eosinophilia in passive cutaneous anaphylactic (PCA) reaction sites. Tissue eosinophilia in systemic PCA showed two phases with peaks at 6 hr and 24 hr, while that in local PCA was monophasic and peaked at 12 hr. A dialysable eosinophil chemotactic factor was isolated from the early stage (0-6 hr) of local PCA skin sites, and another chemotactic factor (mol. wt. 15,000), sharing a common antigenicity with guinea-pig serum C5, from 12-hr-old local PCA skin sites. On the other hand, a different chemotactic factor with a mol. wt. of about 70,000, sharing a common antigenicity with delayed ECF-b isolated from active cutaneous anaphylactic skin lesions, was isolated from 24-hr-old systemic PCA skin lesions. Although the dialysable factor was also isolated from systemic PCA skin sites, the factor from systemic PCA delayed skin sites may not contribute to delayed tissue eosinophilia, since the activity paralleled the intensity of basophil accumulation but not to that of eosinophils. It is thus suggested that tissue eosinophilia in systemic and local PCA reactions is mediated by different chemotactic factors.

Serum eosinophilotactic activity in eosinophilic fasciitis

Serum eosinophil chemotactic activity was determined by the Boyden chamber technique in 20 patients with eosinophilic fasciitis. Increased eosinophil chemotactic activity (greater than 125% of background) was found in all 20 patients (mean 297% +/- 129), whereas sera of 20 controls with systemic sclerosis and diffuse scleroderma had increased eosinophil chemotactic activity in only 6 (30%) instances (mean 96% +/- 47, P less than 0.001). Although serum eosinophil chemotactic activity decreased over time in all 8 eosinophilic fasciitis patients studied longitudinally, this activity returned to normal in only 3, all of whom received prolonged courses of corticosteroids. Preliminary data suggest the existence of a eosinophilotactic serum factor common to patients with eosinophilic fasciitis.