Mechanisms of tolerance to parental parathyroid tissue when combined with human allogeneic thymus transplantation.

BACKGROUND: The induction of tolerance toward third-party solid organ grafts with allogeneic thymus tissue transplantation has not been previously demonstrated in human subjects. OBJECTIVE: Infants with complete DiGeorge anomaly (having neither thymus nor parathyroid function) were studied for conditions and mechanisms required for the development of tolerance to third-party solid organ tissues. METHODS: Four infants who met the criteria received parental parathyroid with allogeneic thymus transplantation and were studied. RESULTS: Two of 3 survivors showed function of both grafts but subsequently lost parathyroid function. They demonstrated alloreactivity against the parathyroid donor in mixed lymphocyte cultures. For these 2 recipients, parathyroid donor HLA class II alleles were mismatched with the recipient and thymus. MHC class II tetramers confirmed the presence of recipient CD4(+) T cells with specificity toward a mismatched parathyroid donor class II allele. The third survivor has persistent graft function and lacks alloreactivity toward the parathyroid donor. All parathyroid donor class II alleles were shared with either the recipient or the thymus graft, with minor differences between the parathyroid (HLA-DRB1∗1104) and thymus (HLA-DRB1∗1101). Tetramer analyses detected recipient T cells specific for the parathyroid HLA-DRB1∗1104 allele. Alloreactivity toward the parathyroid donor was restored with low doses of IL-2. CONCLUSION: Tolerance toward parathyroid grafts in combined parental parathyroid and allogeneic thymus transplantation requires matching of thymus tissue to parathyroid HLA class II alleles to promote negative selection and suppression of recipient T cells that have alloreactivity toward the parathyroid grafts. This matching strategy may be applied toward tolerance induction in future combined thymus and solid organ transplantation efforts.

Resolution of warts in association with subcutaneous immunoglobulin in immune deficiency.

Common variable immunodeficiency is the most common severe primary immunodeficiency. Most common variable immunodeficiency patients have progressive hypogammaglobulinemia involving all immunoglobulin classes, poor or absent antibody responses, and recurrent bacterial infections, usually of the sino-respiratory tract. Some may present with complicated cutaneous infections like furunculosis (J Allergy Clin Immunol; 109: 581) or recurrent cutaneous warts. Here, we report the case of an 18-year-old male diagnosed with common variable immunodeficiency who had extensive cutaneous warts that resolved within 2 months of starting weekly infusions of subcutaneous immunoglobulin.

Etanercept treatment of cutaneous granulomas in common variable immunodeficiency.

Common variable immunodeficiency (CVID) is a primary immunodeficiency characterized by hypogammaglobulinemia, poor antibody responses, and recurrent bacterial infections, usually of the sinorespiratory tract. A not uncommon complication is granuloma of the lungs, spleen, liver, and/or skin. We report the case of an 18-year-old boy with CVID and chronic granulomas of the left arm (since 13 years of age) refractory to treatment with antibiotics, intravenous immunoglobulin, antifungal agents, systemic and intralesional steroids, IFN-gamma, cyclosporine, methotrexate, hydroxychloroquine, localized radiation therapy, and surgical excision. The lesions improved after treatment with the systemic administration of the TNF-alpha inhibitor etanercept for 1 year. Etanercept prevents soluble TNF from binding to its cell membrane receptor, leading to inhibition of its inflammatory cascade. We recommend further trials of etanercept in patients with CVID with noninfectious recalcitrant granulomas.

Pneumococcal seroconversion after vaccination for children with atopic dermatitis treated with tacrolimus ointment.

OBJECTIVE: We sought to determine the effect of treatment with topical tacrolimus on B- and T-cell immunity including the primary antibody response to pneumococcal polysaccharide vaccine in children with atopic dermatitis. METHODS: In this open-label, noncomparative study, 23 children aged 2 to 12 years with moderate to severe atopic dermatitis were treated with tacrolimus 0.03% ointment twice daily for 7 weeks, immunized with a 23-valent pneumococcal polysaccharide vaccine after 3 weeks of treatment, and had their antibody response measured (for 12 pneumococcal serotype antigens present in the vaccine) before and 4 weeks after vaccination. None had received pneumococcal vaccine before the study. Patient antibody and cellular immune responses were assessed at each study visit (baseline, week 3, and week 7). RESULTS: No significant changes in complete blood cell count, lymphocyte subsets, CD4/CD8 ratio, immunoglobulin levels, antibody titers to tetanus and Haemophilus influenzae , or lymphoproliferative responses were noted during the tacrolimus ointment treatment period. Tacrolimus blood levels were 1 ng/mL or less in all 23 children. Protective pneumococcal titers to all 12 serotypes were observed in 2 of 23 (9%) children prevaccination and in 16 of 23 (70%) children postvaccination. All 6 children who had protective titers to 0 to 5 of the 12 serotypes developed protective titers to an additional 5 to 11 serotypes. Of the patients, 91% had a greater than 4-fold increase in titer for at least 4 of 12 pneumococcal serotypes. CONCLUSION: Topical application of tacrolimus ointment does not affect the serologic response to pneumococcal vaccine or interfere with preexisting T- and B-cell immune responses.

Interleukin-15 enhances cytotoxicity, receptor expression, and expansion of neonatal natural killer cells in long-term culture.

Newborn infants have a higher susceptibility to various pathogens due to developmental defects in their host defense system, including deficient natural killer (NK) cell function. In this study, the effects of interleukin-15 (IL-15) on neonatal NK cells was examined for up to 12 weeks in culture. The cytotoxicity of fresh neonatal mononuclear cells (MNC) as assayed by K562 cell killing is initially much less than that of adult MNC but increases more than eightfold after 2 weeks of culture with IL-15 to a level equivalent to that of adult cells. This high level of cytotoxicity was maintained for up to 12 weeks. In antibody-dependent cellular cytotoxicity (ADCC) assays using CEM cells coated with human immunodeficiency virus gp120 antigen, IL-15 greatly increased ADCC lysis by MNC from cord blood. IL-15 increased expression of the CD16+ CD56+ NK markers of cord MNC fivefold after 5 weeks of incubation. Cultures of neonatal MNC with IL-15 for up to 10 weeks resulted in a unique population of CD3- CD8+ CD56+ cells (more than 60%), which are not present in fresh cord MNC. These results show that IL-15 can stimulate neonatal NK cells and sustain their function for several weeks, which has implications for the clinical use of IL-15.

The syndrome of chronic mucocutaneous candidiasis with selective antibody deficiency.

BACKGROUND: Most patients with chronic mucocutaneous candidiasis (CMC) have a selective defect of cell-mediated immunity against Candida albicans (as demonstrated by cutaneous anergy and decreased lymphoproliferative responses to Candida antigen) and intact antibody responses. Many CMC patients also develop infections with other organisms, suggesting a more extensive immunologic defect. OBJECTIVES: The aim of this study was to describe a patient with CMC and selective antibody deficiency and identify eight similar previously reported patients. DATA SOURCES: Relevant articles in the English language derived from searching the MEDLINE database were used. RESULTS: We describe an 18-year-old male patient who was identified with CMC as an infant and later developed immunoglobulin (Ig)G2, IgG4, and IgA deficiency at age 12 associated with poor antibody responses to vaccine antigens. We have identified eight other previously reported CMC patients with selective antibody deficiencies and bacterial infections. IgG2 deficiency was present in all nine patients, and was associated with IgG4 deficiency in 8 patients and IgA deficiency in 3 patients. Six patients had poor or absent antibody responses to pneumococcal polysaccharide vaccine, and all nine patients developed severe recurrent lung infections. CONCLUSIONS: We suggest that these cases represent a distinct phenotype of CMC and should be studied for common histocompatibility leukocyte antigen types and molecular defects.

Treatment of chronic wounds by local delivery of granulocyte-macrophage colony-stimulating factor in patients with neutrophil dysfunction.

Chronic wounds are associated with considerable morbidity and prolonged hospitalizations. The availability of recombinant growth factors and cytokines provides a new modality for treatment of recalcitrant wounds. Granulocyte-macrophage colony-stimulating factor (GM-CSF), a growth protein for hematopietic cells, also enhances neutrophil and monocyte function and promotes keratinocyte proliferation. In three patients with inherited disorders associated with leukocyte dysfunction and non-healing wounds, topical application of GM-CSF resulted in complete wound closure within 1 to 4 weeks. A subcutaneous (s.c.) infusion pump for the local s.c. delivery of GM-CSF was also found to enhance healing. Local application of GM-CSF may thus promote wound closure in patients with impaired wound healing.