Immune mechanisms in atopic dermatitis

Blockade of experimental atopic dermatitis via topical NF-kappaB decoy oligonucleotide

Atopic dermatitis (AD) is a common chronic skin inflammatory disease. Long-term use of topical corticosteroids in skin inflammation poses risks of systemic and local side effects. The NF-kappaB transcription factor family plays a central role in the progression and maintenance of AD. This study explores the possibility of using topical NF-kappaB Decoy as a novel therapeutic alternative for targeting Th1/Th2-driven skin inflammation in experimental AD. A high-affinity, topical NF-kappaB Decoy developed for human efficacy demonstrates: (i) efficient NF-kappaB Decoy penetration in pig skin, (ii) NF-kappaB Decoy nuclear localization in keratinocytes and key immune cells, and (iii) potent "steroid-like" efficacy in a chronic dust-mite antigen skin inflammation treatment model. NF-kappaB Decoy exerts its anti-inflammatory action through the effective inhibition of essential regulators of inflammation and by induction of apoptosis of key immune cells. Unlike betamethasone valerate (BMV), long-term NF-kappaB Decoy treatment does not induce skin atrophy. Moreover, topical NF-kappaB Decoy, in contrast to BMV, restores compromised stratum corneum integrity and barrier function. Steroid withdrawal causes rapid rebound of inflammation, while the NF-kappaB Decoy therapeutic benefit was maintained for weeks. Thus, topical NF-kappaB Decoy provides a novel mechanism of reducing chronic skin inflammation with improved skin homeostasis and minimal side effects.

Fc epsilon receptor II/CD23 positive lymphocytes in atopic dermatitis: II. Infiltration of Fc epsilon R II(+) T cells in the skin lesion

Cells expressing Fc receptors for IgE (Fc epsilon R II) were identified in skin from patients with atopic dermatitis (AD), eczematous dermatitis (ED), and in skin from normal nonatopic subjects, with the use of monoclonal antibodies to human lymphocyte Fc epsilon R II, H107, and to lymphoid cell-surface antigens by double immunofluorescence staining. Two to four percent of infiltrating mononuclear cells expressed Fc epsilon R II, and more than half of these cells were T epsilon cells in both acute and chronic AD lesions. Fc epsilon R II(+) T cells (T epsilon cells) bearing CD8 infiltrated preferentially acute lesions, whereas chronic lesions contained either CD8(+) or CD4(+) T epsilon cells, or both. Fc epsilon R II(+) cells rarely were present in ED lesions. There was no significant correlation between % Fc epsilon R II(+) peripheral blood mononuclear cells and the proportion of lesional Fc epsilon R II(+) cells, extent of skin lesions, or serum IgE levels, implying the selective accumulation of Fc epsilon R II(+) cells in the inflammatory infiltrate of AD. These observations suggest that the increased generation of Fc epsilon R II(+) cells in skin lesions, including CD8 (+) T epsilon cells, is involved in the pathogenesis of AD.

Long-term survival after bone marrow transplantation: a 15-year follow-up report of a patient with Wiskott-Aldrich syndrome

In 1968 a 2-year-old boy with Wiskott-Aldrich syndrome was extremely ill with eczema, a series of life-threatening infections, and repeated hemorrhages into his skin, lungs, brain, and other internal organs. He was given high-dose cyclophosphamide therapy for immunosuppression, followed by bone marrow cells from his histocompatible, healthy sister. In the 15 years since bone marrow transplantation, he has had full T cell, partial B cell, and no hematopoietic engraftment. He has weathered the usual infectious diseases of childhood, has had no serious infections, and despite persistent thrombocytopenia has not had serious bleeding episodes.

T-cell dysfunctions in IgA nephropathy: specific abnormalities in the regulation of IgA synthesis

This work was undertaken to determine the cellular abnormalities that could explain the high levels of serum IgA frequently found in patients with IgA nephropathy. Seventeen control subjects and twenty-seven patients who had received no therapy were studied. After in vitro pokeweed mitogen (PWM) stimulation, significantly higher amounts of IgA were produced by peripheral blood mononuclear cells (PBM) of patients when compared with those of the control group (560 +/- 97 vs 231 +/- 57 ng/ml, P less than 0.0025). No differences were observed in the synthesis of IgG and IgM. Twenty out of twenty-seven patients presented an increase in the percentages of OKT4+ cells (mean + 2 SD), in relation to the control group, with normal or elevated percentages of OKT8+ cells. The OKT4+/OKT8+ cell ratio was elevated in 12 out of 27 patients. All patients presented some abnormality in the generation of IgA-specific suppressor cells at variable doses of concanavalin A (Con A) on in vitro PWM-stimulated culture of PBM. In both assays low doses of Con A (2.5 micrograms/ml) induced a certain suppression of IgA synthesis in patients that was not observed in the majority of the control group. At these doses some patients also showed an enhancement in the synthesis of IgG and IgM. On the contrary, higher doses of Con A (50 micrograms/ml) produced significantly less IgA suppression than the controls. Normal IgA-suppression values were found at 10 micrograms/ml of Con A. T cells obtained from patients were significantly more efficient than T cells from controls in providing IgA-helper activity for normal allogeneic enriched B cells (P less than 0.025) in PWM-stimulated cocultures. These results show that patients with IgA nephropathy present, after mitogen stimulation in vitro, a specifically increased production of IgA as well as an augmentation in the activity of IgA-helper T cell and a deregulation on IgA-suppressor T-cell function. According to these data, it is suggested that the alteration observed in helper T cells might precede that of suppressor T cells. These immunoregulatory abnormalities might contribute to the pathogenesis of the disease.