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S Anan

Publications and source records attributed to S Anan.

At least 19 recordsLinked to original sources
PubMed1996

Affinity-purified Dermatophagoides farinae antigen induces CD23 on T and B lymphocytes and monocytes specifically in patients with atopic dermatitis.

The purpose of this work is to analyze CD23 expression on subpopulations of peripheral blood mononuclear cells (PBMC) from the patients with atopic dermatitis (AD) after stimulation with affinity-purified Dermatophagoides farinae antigen (Af-DF). PBMC from mite-allergic AD patients stimulated with Af-DF induced striking expression of CD23 after the culture. The frequencies of CD23-positive (CD23+) PBMC in the culture were significantly higher than those without stimulation. Most of the CD23+ cells belonged to B lymphocytes and monocytes subsets. CD23 was induced in less than 1% of CD3+, CD4+ and CD8+ lymphocytes by Af-DF. However, significant differences were observed compared to the spontaneous expression, and dose-dependencies were confirmed. No significant increase in the frequencies of CD23+ PBMC was found in non-mite-allergic AD patients and non-atopic donors after stimulation with Af-DF. The kinetics of CD23 expression by Af-DF showed similar patterns to that by IL-4 stimulation. Our results demonstrate that Af-DF can induce CD23 expression on PBMC in mite-allergic AD patients. Based on the high titer of mite-specific IgE antibody in blood of AD, mite antigen may, at least in part, contribute to high CD23 expression in AD.

Adolescent↗
PubMed1996

Immunoglobulins and their receptors on epidermal Langerhans cells in atopic dermatitis.

To elucidate the etiological role of immunoglobulin molecules on Langerhans cells (LCs) in atopic dermatitis, we conducted immuno-histochemical studies on the localization of immunoglobulin G1 (IgG1), IgG2, IgG3, IgG4, IgA and IgM on epidermal LCs from 30 patients with atopic dermatitis (AD) and five non-atopic healthy volunteers. We also investigated the types of receptors for the immunoglobulins (Fc epsilon RI, Fc epsilon RII, Fc gamma RI, Fc gamma RII, and Fc gamma RIII) on epidermal LCs in the patients. IgE positive epidermal LCs were observed in 28 of 30 AD patients, and 46.7% of the epidermal LCs were positive for IgE. Both IgG1- and IgG2-positive epidermal LCs were observed in 70% of AD patients, and 21.8% and 28.7% of the total epidermal LCs were positive for IgG1 and IgG2, respectively. IgG3- or IgG4-positive LCs were present in only small proportions of AD patients. IgA-positive LCs were observed in 8 AD patients; our study suggested that the IgA bound on LCs was secretory IgA (S-IgA). These surface immunoglobulins were observed significantly more frequently on epidermal LCs in the involved skin of AD than in clinically uninvolved skin. No IgM-positive epidermal LCs were observed in the AD patients or healthy volunteers. In non-atopic healthy controls, no immunoglobulin-binding LCs were observed. In receptors for immunoglobulins, Fc epsilon RI and Fc gamma RII were exclusively expressed on nearly all epidermal LCs from all AD patients and all non-atopic controls. These results suggested that not only IgE but also IgG and IgA may play some etiological role in the pathogenesis of AD.

Adolescent↗
PubMed1995

High affinity IgE receptor (Fc epsilon RI) expression on eosinophils infiltrating the lesions and mite patch tested sites in atopic dermatitis.

Expression of the high affinity IgE receptor (Fc epsilon RI) on eosinophils has recently been reported. This led us to evaluate Fc epsilon RI expression on eosinophils in atopic dermatitis (AD). Double immunofluorescence stainings with an anti-Fc epsilon RI monoclonal antibody (mAb) and a polyclonal antieosinophil cationic protein (ECP) antibody were performed on lesional biopsy specimens from patients with AD and from patients with bullous pemphigoid (BP) as controls. In AD and BP lesions, 77% and 70% of eosinophils expressed Fc epsilon RI, respectively. However, the intensity of Fc epsilon RI staining in AD was much stronger than in BP, suggesting upregulation of Fc epsilon RI expression on eosinophils in AD. In addition, the eosinophils infiltrating AD lesions were stained strongly with anti-CD23 mAb and anti-IgE antibody. At the sites of mite patch testing in AD, Fc epsilon RI-, CD23- and IgE-positive eosinophils were observed to the same degree as in the lesions, and a considerable number of mite antigen-bearing eosinophils were detected. Fc epsilon RI and CD23 were both upregulated on the skin-infiltrating eosinophils in AD and bound IgE molecules.

Adult↗
PubMed1995

High affinity IgE receptor-mediated prostaglandin E2 production by monocytes in atopic dermatitis.

High affinity IgE receptor (Fc epsilon R I) expression on monocytes and its upregulation on monocytes from patients with atopic dermatitis (AD) have been recently reported. In this study, we investigated whether prostaglandin E2 (PGE2) release from AD monocytes was Fc epsilon R I-dependent or not. The monocytes were stimulated with anti-Fc epsilon R I monoclonal antibody (mAb) and anti-Fc epsilon R II mAb. Cross-linking of Fc epsilon R I, but not that of Fc epsilon R II induced PGE2 release from monocytes. In order to confirm that the PGE2 release is IgE-dependent, stimulation with IgE+anti-IgE, IgG+anti-IgG and immune complexes made by incubation with AD patients' serum and recombinant Der fII (rDer fII-IC) were carried out in the culture. Significant PGE2 release by all the stimulants was observed, as compared with spontaneous release. PGE2 release by immune complex made by incubation with IgE-absorbed AD serum and rDer fII was much lower than that by rDer fII-IC. In monocytes from nonatopic donors, significant PGE2 release was observed when stimulated with IgE+anti-IgE, IgG+anti-IgG, rDer fII-IC, but not with anti-FC epsilon R I mAb and anti-Fc epsilon R II mAb. However, the release were significantly lower than respective PGE2 releases from AD monocytes. Taken together, cross-linking of Fc epsilon R I and IgE induced a PGE2 release from monocytes. This is a first report demonstrating an Fc epsilon R I-dependent mediator release from monocytes of AD patients.

Antigen-Antibody Complex↗
PubMed1992

Contact hypersensitivity reaction to ovalbumin in newborn guinea pigs from maternally sensitized animals.

An animal study was conducted to elucidate the role of ovalbumin (OA) in the development of eczematous lesions in intrauterine sensitized newborns. Four groups of pregnant guinea pigs were used: group A, immunized by oral administration of 1% OA in drinking water until parturition; group B, immunized by intradermal injection of OA with Freund's complete adjuvant; group C, immunized by both methods; and group D (control), not immunized. The newborn guinea pigs of each group were patch tested with 10% OA in white petrolatum. Positive reactions were seen in the newborns of groups B and C, but not in those in groups A and D. By enzyme-linked immunosorbent assay and passive cutaneous anaphylaxis, a high titre of OA-specific IgG was detected in the group B and C newborns. The number of positive patch test reactions decreased concomitantly with the decline of specific IgG. Histologically, eczematous changes were observed in the positive reaction sites. Many OA antigen-bearing Langerhans cells were found by the immuno-double labelling technique. Immuno-electron microscopic findings revealed the presence of OA antigens as well as IgG molecules on the cytoplasmic membranes of Langerhans cells. Our studies demonstrated that maternal sensitization with OA can induce an eczematous reaction in the newborns to OA patch testing under the presence of high levels of OA-specific IgG in the serum. From these findings it is suggested that IgG plays an essential role in the development of contact hypersensitivity reaction to OA.

Administration, Oral↗
PubMed1992

The relationship between eosinophils, OKT6-positive cells and house dust mite (HDM) antigens in naturally occurring lesions of atopic dermatitis.

To determine the role of eosinophils in naturally occurring lesions of atopic dermatitis, we observed the distribution of eosinophil cationic protein (ECP) and the relationship between eosinophils, OKT6-positive cells and house dust mite (HDM) antigens. Some specimens showed many EG2-positive stains, although the accumulation of tissue eosinophils was not prominent. EG2 stains were seen not only in eosinophils but also in extracellular granules. Some macrophage-like cells of the dermis showed EG2 stains in the form of phagocytized eosinophil granules. Some EG2-positive eosinophils were in close contact with OKT6-positive cells in the epidermis and dermis. Furthermore, in three patients sensitive to house dust mite (HDM) antigen, HDM antigens invaded the skin with many EG2-positive stains. These results suggest that eosinophils play an active role in the development of eczematous lesions of atopic dermatitis.

Adolescent↗
PubMed1992

House dust mite (HDM) antigen in naturally occurring lesions of atopic dermatitis (AD): the relationship between HDM antigen in the skin and HDM antigen-specific IgE antibody.

To elucidate the etiological role of house dust mite (HDM) antigen in the pathogenesis of atopic dermatitis (AD), we conducted immunohistochemical studies on the localization of HDM antigen in naturally occurring lesions of AD. HDM antigens were found in the epidermis and dermis in 19 of 38 cases. All of the 19 patients had HDM antigen-specific IgE antibody, but HDM antigen was not detected in the lesions of patients without HDM antigen-specific IgE or in control skin specimens. Most HDM antigens were located on Langerhans cells (LCs) or near helper T cells. Our findings suggest that HDM antigen is the causative factor in the development of eczematous lesions of AD, and thus we hypothesized that IgE-mediated allergic contact sensitivity to HDM antigen plays an important role in the pathogenesis of AD.

Adolescent↗
PubMed1991

[Clinical significance of specific IgG4 antibody in serum].

Specific IgG4 antibodies in sera were measured by ELISA in allergic patients who were diagnosed as susceptible to one or more allergens among mite, milk, soybean or egg white, and also in a non-allergic control group, and their diagnostic significance was investigated. The results obtained were as follows. 1. The level of specific IgG4 antibody was significantly higher in each allergic group than in the non-allergic group. 2. The positive rates in the specific IgG4 antibody determination were higher than those in RAST in the milk-, soybean- and egg white-allergic groups. 3. In each allergic group, the causative allergens were detected more accurately by measuring both specific IgG4 antibody and IgE antibody (RAST) than IgE alone. 4. The positive rates in the specific IgG4 antibody determination were higher than those in the skin test in each allergic group. 5. It was demonstrated that the combination of the skin test with specific IgG4 antibody measurement ensured a more accurate detection of causative allergens than the skin test alone. These results indicated that the measurement of the specific IgG4 antibody is a helpful method to detect the causative allergens in allergic patients.

Adolescent↗
PubMed1990

Immunohistochemical studies in mite antigen-induced patch test sites in atopic dermatitis.

The role of mite allergen in atopic dermatitis is still unclear. In this study, we investigated whether an eczematous reaction could be induced by patch testing with dust mite antigen. We succeeded in reproducing an eczematous lesion and the mite RAST-positive AD group showed a positive reaction much more than the RAST-negative group. Many mite antigen-bearing Langerhans cells, also possessing IgE molecules, were found by the use of an immuno-double labelling technique. By using immunoelectron microscopy, it was observed that the mite antigens were trapped by some macrophages, which were apposed to lymphocytes. To investigate the time-course of the reaction, the patch test reactions were read and biopsied after 1 h, 6 h, 24 h and 48 h. An eczematous reaction developed 24 h after patch testing. The mite antigen-bearing Langerhans cells were seen exclusively in the epidermis after 6 h, and mainly in the dermis after 24 h and 48 h. These results suggested that IgE-mediated contact hypersensitivity to mite antigen may develop and play an important role in AD.

Adolescent↗
PubMed1989

Immunohistochemical studies on dust mite antigen in positive reaction site of patch test.

We demonstrated that eczematous reactions could be induced by patch testing with mite antigens in the majority of patients with atopic dermatitis (AD). By using immuno-double labelling technique, many mite antigen-bearing Langerhans cells were seen in the epidermis in the early stage of the patch testing. Twenty-four hours later, these cells were observed only in the deep dermis. Immunoelectron microscopically, it was found that the mite antigens were trapped by macrophages, which were apposing lymphocytes. On the other hand, we observed that Langerhans cells and Leu 3a positive cells in the AD lesions carried IgE molecules. Furthermore, many IgE-positive dendritic cells bearing mite antigen were seen in the positive patch testing sites. Taken together, IgE-mediated contact hypersensitivity to mite antigen may play an important role in the pathogenesis of AD.

Adolescent↗
PubMed1985

Suppressor T lymphocyte induction by a factor released from cultured blastocysts.

For the analysis of immunologic escape mechanisms of embryos during the implantation period in mice, the effects of culture supernatant of blastocysts on in vitro responsiveness to alloantigen of mice was investigated. Blastocyst-cultured conditioned medium was prepared by culturing late blastocysts of outbred ICR mice for 5 days. The addition of culture supernatant containing four or eight blastocysts to allogeneic mixed lymphocyte culture inhibited both the MLR responses and the generation of cytotoxic T lymphocytes (CTL). Preincubation of the culture supernatant with lymphocytes syngeneic to the responder cells of MLR induced potent suppressor cell activity in the MLR. The supernatant did not inhibit the activity of CTL at the effector phase, but preinduced suppressor cells obtained by incubation of splenocytes with the supernatant showed almost complete suppression of CTL activity at the effector phase. Both of the suppressor cells, active on MLR and at the generation phase of CTL as well as active at the effector phase, had a surface phenotype of Thy-1+ and Ig-. The suppressive material could be extracted from the eight-cell stage of fertilized ova or blastocysts but not from unfertilized ova, indicating that the production of the factor(s) is dependent on the stages of early embryogenesis. These results suggest that the active induction of suppressor T lymphocytes by the factor(s) released from implanted embryos is one of the protective mechanisms from maternal immunologic attack.

Animals↗
PubMed1983

Circulating immune complexes and their possible relevance to other immunological parameters in Guatemalan onchocerciasis.

Circulating immune complexes (CIC) were demonstrated in sera of Guatemalan patients with onchocerciasis by Raji cell radioimmunoassay. 44% of patients but none of controls had abnormally high concentrations of CIC in their sera. The increased concentrations of CIC were found more frequently in patients with lower density of microfilariae in their skin biopsies. Patients with higher concentrations of CIC appeared to have increased titers of serum antibodies to Onchocerca volvulus. A depression of both humoral immune response to tetanus toxoid and delayed hypersensitivity reaction to PPD were found in patients with onchocerciasis. CIC may be involved in modulation of the immune response in onchocerciasis.

Adolescent↗
PubMed1982

Ultrastructural studies of eosinophils in passive cutaneous anaphylaxis.

Kinetics and ultrastructural changes of eosinophils in passive cutaneous anaphylaxis in guinea pigs were studied. Ovalbumin was used. Skin biopsies were studied with the electron microscope. Degranulation of eosinophils in the vascular lumen, the vascular wall, and in the surrounding of vessels was noted. There was edema and degeneration of collagen fibers.

Animals↗