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Objective: To measure azithromycin (AZM) concentrations in serum and bronchial secretions in patients with cystic fibrosis (CF) and chronic Pseudomonas aeruginosa pulmonary infection. Patients and Methods: 10 CF patients (four male, six female; mean age 29 ± 10 years) with chronic P. aeruginosa pulmonary infection were randomised to receive either 500 or 1000mg of AZM (five patients per group) orally once daily for 5 days. Concentrations of AZM in serum and bronchial secretions (obtained after physiotherapy) were evaluated every 24 hours for the 5 days of administration and the following 6 days. Main Outcome Measures and Results: High AZM concentrations were found in bronchial secretions, persisting after drug administration had ended. Mean concentrations were ≥ 4 mg/L for the 1000 mg/day dose from day 2 to 11 and >2 mg/L for the 500 mg/day dose from day 2 to day 10. Serum AZM concentrations were much lower (<0.4 mg/L for the 1000 mg/day, and <0.2 mg/L for the 500 mg/day, dosage). Conclusions: These data appear to indicate the possibility of obtaining in vivo AZM concentrations previously shown to inhibit production of virulence factors in P. aeruginosa in vitro. We consider that clinical trials evaluating prolonged administration of AZM to CF patients would be both useful and justifiable. [ABSTRACT FROM AUTHOR]

Seventeen adult volunteers were vaccinated orally with the live attenuated Salmonella typhi mutant strain Ty21a. Their peripheral blood mononuclear cells were tested at different times after vaccination for direct cell-mediated activity against bacteria, employing a simple short-term in vitro assay. It was observed that 16/17 of the vaccinated subjects acquired the capacity to express specific cellular immunity against S. typhi which lasted from 15 days to at least 3 years. The effector cell of the in vitro antibacterial activity was preliminarily characterized as a non-adherent T3+,T8-,T4+ lymphocyte. In parallel, mice immunized orally with S. typhimurium and proving resistant to reinfection were tested employing the same in vitro assay. Also in this case peripheral and, most important, intestinal lymphocytes were able to express cellular immunity against the agent of murine typhoid. It is concluded that administration of live oral vaccine against S. typhi results in the induction of specific cellular immunity which is expressed at the peripheral and, probably, also at the intestinal level. [ABSTRACT FROM AUTHOR]

Fibroblasts from a patient with ICF syndrome were grown in the presence of excess of nucleotides, in media with different amounts of folic acid, and with caffeine in an attempt to induce the chromosomal anomalies observed in lymphocytes. We induced despiralisation and breakages in the centromeric heterochromatin of chromosomes 1 and 16 but not associations and multibranching. We suggest that the absence of the major chromosomal anomalies in fibroblasts from patients with ICF might be the result of both a longer G2 in these cells and differential patterns of interphase heterochromatin associations in the two tissues. [ABSTRACT FROM PUBLISHER]

Mutations of forkhead box p3 (FOXP3), the master gene for naturally occurring regulatory T cells (nTregs), are responsible for the impaired function of nTregs, resulting in an autoimmune disease known as the immune dysregulation, polyendocrinopathy, enteropathy, X-linked (IPEX) syndrome. The relevance of other peripheral tolerance mechanisms, such as the presence and function of type 1 regulatory T (Tr1) cells, the major adaptive IL-10-producing Treg subset, in patients with IPEX syndrome remains to be clarified. FOXP3(mutated) Tr1-polarized cells, differentiated in vitro from CD4(+) T cells of four IPEX patients, were enriched in IL-10(+) IL-4(-) IFN-γ(+) T cells, a cytokine production profile specific for Tr1 cells, and expressed low levels of FOXP3 and high levels of Granzyme-B. IPEX Tr1 cells were hypoproliferative and suppressive, thus indicating that FOXP3 mutations did not impair their function. Furthermore, we isolated Tr1 cell clones from the peripheral blood of one FOXP3(null) patient, demonstrating that Tr1 cells are present in vivo and they can be expanded in vitro in the absence of WT FOXP3. Overall, our results (i) show that functional Tr1 cells differentiate independently of FOXP3, (ii) confirm that human Tr1 and nTregs are distinct T-cell lineages, and (iii) suggest that under favorable conditions Tr1 cells could exert regulatory functions in IPEX patients., (Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Forkhead box P3 (FOXP3) is constitutively expressed by CD4(+)CD25(hi) regulatory T cells (nTregs). Mutations of FOXP3 cause a severe autoimmune syndrome known as immune dysregulation polyendocrinopathy enteropathy X-linked, in which nTregs are absent or dysfunctional. Whether FOXP3 is essential for both differentiation and function of human nTreg cells remains to be demonstrated. Because FOXP3 is an X-linked gene subject to X-chromosome inactivation (XCI), we studied 9 healthy female carriers of FOXP3 mutations to investigate the role of wild-type (WT) versus mutated FOXP3 in different cell subsets. Analysis of active WT versus mutated (mut)-FOXP3 allele distribution revealed a random pattern of XCI in peripheral blood lymphocytes and in naive and memory CD4(+)T cells, whereas nTregs expressed only the active WT-FOXP3. These data demonstrate that expression of WT-FOXP3 is indispensable for the presence of a normal nTreg compartment and suggest that FOXP3 is not necessary for effector T-cell differentiation in humans.

Background: Immune dysregulation, polyendocrinopathy, enteropathy, X-linked (IPEX) syndrome is an autoimmune genetic disorder caused by mutation of the forkhead box protein 3 gene (FOXP3), a key regulator of immune tolerance., Objective: We sought to provide clinical and molecular indicators that facilitate the understanding and diagnosis of IPEX syndrome., Methods: In 14 unrelated affected male subjects who were given diagnoses of IPEX syndrome based on FOXP3 gene sequencing, we determined whether particular FOXP3 mutations affected FOXP3 protein expression and correlated the molecular and clinical data., Results: Molecular analysis of FOXP3 in the 14 subjects revealed 13 missense and splice-site mutations, including 7 novel mutations. Enteropathy, generally associated with endocrinopathy and eczema, was reported in all patients, particularly in those carrying mutations within FOXP3 functional domains or mutations that altered protein expression. However, similar genotypes did not always result in similar phenotypes in terms of disease presentation and severity. In addition, FOXP3 protein expression did not correlate with disease severity., Conclusion: Severe autoimmune enteropathy, which is often associated with increased IgE levels and eosinophilia, is the most prominent early manifestation of IPEX syndrome. Nevertheless, the disease course is variable and somewhat unpredictable. Therefore genetic analysis of FOXP3 should always be performed to ensure an accurate diagnosis, and FOXP3 protein expression analysis should not be the only diagnostic tool for IPEX syndrome.

Agammaglobulinemia is a rare primary immunodeficiency characterized by an early block of B cell development in the bone marrow, resulting in the absence of peripheral B cells and low/absent immunoglobulin serum levels. So far, mutations in Btk, mu heavy chain, surrogate light chain, Igalpha, and B cell linker have been found in 85-90% of patients with agammaglobulinemia. We report on the first patient with agammaglobulinemia caused by a homozygous nonsense mutation in Igbeta, which is a transmembrane protein that associates with Igalpha as part of the preBCR complex. Transfection experiments using Drosophila melanogaster S2 Schneider cells showed that the mutant Igbeta is no longer able to associate with Igalpha, and that assembly of the BCR complex on the cell surface is abrogated. The essential role of Igbeta for human B cell development was further demonstrated by immunofluorescence analysis of the patient's bone marrow, which showed a complete block of B cell development at the pro-B to preB transition. These results indicate that mutations in Igbeta can cause agammaglobulinemia in man.

Azithromycin is used for the treatment of cystic fibrosis lung disease, although its mechanisms of action are not completely understood. Besides its antiinflammatory and antimicrobial activities, one possibility could be the overexpression induction of the multidrug resistance-associated protein (MRP), which could affect chloride transport, thus overcoming the ion transport defect of cystic fibrosis. Seven patients were evaluated before and after 4 weeks of azithromycin treatment (500 mg once daily). Ion transport was studied in vivo by measuring nasal potential difference (NPD). MRP mRNA expression was studied in nasal cells by an internal standard-based semiquantitative RT-PCR assay. NPD was consistent with cystic fibrosis before treatment. After azithromycin treatment, sodium transport was still impaired, whereas a significant increase in chloride conductance was observed (p = 0.03). A significant direct correlation was found between MRP mRNA expression levels and NPD chloride response after azithromycin treatment (p = 0.04, r = 0.78). In conclusion, azithromycin may induce MRP overexpression and restore chloride conductance in the airways of cystic fibrosis patients. These findings suggest a new potential role of azithromycin in the treatment of cystic fibrosis pulmonary disease, i.e. the possibility to upregulate proteins whose function may, at least in part, compensate for the basic defect of cystic fibrosis.

A questionnaire-based retrospective clinical and immunological survey was conducted in 73 males with a definite diagnosis of X-linked agammaglobulinemia based on BTK sequence analysis. Forty-four were sporadic and 29 familial cases. At December 2000, the patients' ages ranged from 2 to 33 years; mean age at diagnosis and mean duration of follow-up were 3.5 and 10 years respectively. After the mid-1980s all but 2 were on intravenous immunoglobulin (IVIG) substitution therapy, with residual IgG >500 mg/dl in 94% of the patients at the time of enrollment. Respiratory infections were the most frequent manifestation both prior to diagnosis and over follow-up. Chronic lung disease (CLD) was present in 24 patients, in 15 already at diagnosis and in 9 more by 2000. The cumulative risk to present at diagnosis with CLD increased from 0.17 to 0.40 and 0.78 when the diagnosis was made at the ages of 5, 10, and 15 years respectively. For the 9 patients who developed CLD during follow-up, the duration of follow-up, rather than age at diagnosis; previous administration of intramuscular immunoglobulin; and residual IgG levels had a significant effect on the development of CLD. Chronic sinusitis was present in 35 patients (48%), in 15 already at diagnosis and in 20 by 2000. Sistemic infections such as sepsis and meningitis/meningoencephalitis decreased over follow-up, probably due to optimal protection provided by high circulating IgG levels reached with IVIG.

In September 1997, a 25-year-old Italian woman with cystic fibrosis (CF) spent 3 weeks in Thailand. In August 1998, her pulmonary function rapidly declined, with productive cough and intermittent fever. Chest x-ray films revealed diffuse, small, patchy opacities in the upper lobes. Burkholderia pseudomallei (BP) was isolated from specimens of the patient's sputum and was identified by means of 16S rDNA sequencing. The diagnosis of melioidosis was serologically confirmed. Continuous therapy with ceftazidime and co-trimoxazole and maintenance with co-trimoxazole, doxycycline, and chloramphenicol resulted in eradication of BP. We present the issue of whether patients with CF represent a population particularly at risk for melioidosis.

Neutrophil motility and superoxide anion production and serum immunoglobulin levels were assessed in 51 children with recurrent infections of the lower respiratory tract and chronic bronchial suppuration, not due to anatomic or functional cause. In 26 children (50.9%), a significant defect of the immunologic defenses, likely to be responsible for the disease, was observed. A precocious diagnosis and an adequate therapy could result, at least in some patients, in the prevention of progressive lung damage.

Two episodes of acute iron deficiency anemia with blood-stained sputum and symptoms of severe acute pulmonary exacerbation were observed in a child with cystic fibrosis (CF). Hemosiderin laden macrophages (siderophages) were repeatedly found in sputum and gastric juice, suggesting the coexistence of pulmonary hemosiderosis (PH). The possibility that pulmonary immune-mediated mechanisms characteristic of CF may have played a role in the development of PH is considered.