Dewton de Moraes Vasconcelos

Low Penetrance, Broad Resistance, and Favorable Outcome of Interleukin 12 Receptor β1 Deficiency Medical and Immunological Implications

The clinical phenotype of interleukin 12 receptor β1 chain (IL-12Rβ1) deficiency and the function of human IL-12 in host defense remain largely unknown, due to the small number of patients reported. We now report 41 patients with complete IL-12Rβ1 deficiency from 17 countries. The only opportunistic infections observed, in 34 patients, were of childhood onset and caused by weakly virulent Salmonella or Mycobacteria (Bacille Calmette-Guérin -BCG- and environmental Mycobacteria). Three patients had clinical tuberculosis, one of whom also had salmonellosis. Unlike salmonellosis, mycobacterial infections did not recur. BCG inoculation and BCG disease were both effective against subsequent environmental mycobacteriosis, but not against salmonellosis. Excluding the probands, seven of the 12 affected siblings have remained free of case-definition opportunistic infection. Finally, only five deaths occurred in childhood, and the remaining 36 patients are alive and well. Thus, a diagnosis of IL-12Rβ1 deficiency should be considered in children with opportunistic mycobacteriosis or salmonellosis; healthy siblings of probands and selected cases of tuberculosis should also be investigated. The overall prognosis is good due to broad resistance to infection and the low penetrance and favorable outcome of infections. Unexpectedly, human IL-12 is redundant in protective immunity against most microorganisms other than Mycobacteria and Salmonella. Moreover, IL-12 is redundant for primary immunity to Mycobacteria and Salmonella in many individuals and for secondary immunity to Mycobacteria but not to Salmonella in most.

Immune cells and oxidative stress in the endotoxin tolerance mouse model

Sepsis is a systemic inflammatory response that can lead to tissue damage and death. In order to increase our understanding of sepsis, experimental models are needed that produce relevant immune and inflammatory responses during a septic event. We describe a lipopolysaccharide tolerance mouse model to characterize the cellular and molecular alterations of immune cells during sepsis. The model presents a typical lipopolysaccharide tolerance pattern in which tolerance is related to decreased production and secretion of cytokines after a subsequent exposure to a lethal dose of lipopolysaccharide. The initial lipopolysaccharide exposure also altered the expression patterns of cytokines and was followed by an 8- and a 1.5-fold increase in the T helper 1 and 2 cell subpopulations. Behavioral data indicate a decrease in spontaneous activity and an increase in body temperature following exposure to lipopolysaccharide. In contrast, tolerant animals maintained production of reactive oxygen species and nitric oxide when terminally challenged by cecal ligation and puncture (CLP). Survival study after CLP showed protection in tolerant compared to naive animals. Spleen mass increased in tolerant animals followed by increases of B lymphocytes and subpopulation Th1 cells. An increase in the number of stem cells was found in spleen and bone marrow. We also showed that administration of spleen or bone marrow cells from tolerant to naive animals transfers the acquired resistance status. In conclusion, lipopolysaccharide tolerance is a natural reprogramming of the immune system that increases the number of immune cells, particularly T helper 1 cells, and does not reduce oxidative stress.

Leprosy and Tuberculosis Co-Infection: Clinical and Immunological Report of Two Cases and Review of the Literature

A review of the records of patients seen between 2004 and 2011 at the Dermatology Clinic of the São Paulo University Medical School showed that only two leprosy patients had been co-infected with tuberculosis (TB). One patient showed a type 1 leprosy reaction during the first 3 months of treatment of pleural TB and in the other patient, pulmonary TB was diagnosed during the first 3 months of treatment of a type 1 leprosy reaction. Both patients showed normal cellular immune response tests, including those of the interferon-gamma (IFN-γ)/interleukin 12 (IL-12) axis. Although both mycobacterial infections are endemic in developing countries like Brazil, the co-infection has hardly been reported in the last decade. There is no suitable explanation for this observation. The reports on the interaction between the two mycobacteria are highly speculative: some studies suggest that leprosy, especially the anergic form, would predispose to TB, whereas other investigations suggested an antagonism between the two diseases.

Endotoxin tolerance: selective alterations in gene expression and protection against lymphocyte death.

Extensive lymphocyte apoptosis may be an important cause of immune suppression in sepsis. Here we investigated the effect of LPS tolerance on lymphocyte apoptosis in an experimental model of polymicrobial infection. Tolerance was induced by the injection of lipopolysaccharide (1.0mg/kg/subcutaneously) once a day for 5 days. Macroarray analysis of mRNA isolated from T-(CD4) lymphocytes was used to identify genes that are differentially expressed during LPS tolerance. In addition, assessment of the expression of apoptosis-associated lymphocyte gene products and apoptotic events was performed on the 8th day; 6h after the terminal challenge with polymicrobial infection or high-dose LPS administration. Survival studies with polymicrobial infection were also conducted. LPS tolerance induced a broad reprogramming of cell death pathways, including a suppression of receptor-mediated and mitochondrial apoptotic pathways, inflammatory caspases, alternate apoptotic pathways, as well as reduced expression of genes involved in necrosis. These alterations led to a marked resistance of lymphocytes against cell death during the subsequent period of sepsis. In addition, LPS tolerance produced an increased differentiation of T-lymphocytes to T(H)1 and T(H)2, with a T(H)1 differentiation predominance. Thus, in the current study we provide an evidence for a marked reprogramming of gene expression of multiple cell death pathways during LPS tolerance. These alterations may play a significant role in the observed protection of the animals from a subsequent lethal polymicrobial sepsis challenge.

Polarized light microscopy of hair shafts aids in the differential diagnosis of Chédiak-Higashi and Griscelli-Prunieras syndromes

PURPOSE To study and compare the appearance of hairs from patients with Chédiak-Higashi and Griscelli-Prunieras syndromes under light and polarized light microscopy. METHOD Hairs from 2 Chédiak-Higashi and 2 Griscelli-Prunieras patients were obtained and examined under normal and polarized light microscopy. RESULTS Under light microscopy, hairs from Chédiak-Higashi patients presented evenly distributed, regular melanin granules, larger than those seen in normal hairs. Under polarized light microscopy, shafts exhibited a bright and polychromatic refringence appearance. In contrast, hair from Griscelli-Prunieras patients, under light microscopy, exhibited bigger and irregular melanin granules, distributed mainly near the medulla. Under polarized light microscopy, shafts appeared monotonously white. CONCLUSION Light microscopic examination of hair shafts of patients with Chédiak-Higashi or Griscelli-Prunieras syndrome reveals subtle differences that are useful in identifying both disorders, but not in distinguishing between them. We provide evidence that polarized light microscopy of hair shafts, an approach that has not been previously described, aids in differentiating between these syndromes. We propose hair study by polarized light microscopy as a helpful complementary diagnostic method for differential diagnosis between CHS and GPS, especially when the more sophisticated molecular studies are not available.

Identification of XP Complementation Groups by Recombinant Adenovirus Carrying DNA Repair Genes

lyzed in skin-draining lymph nodes (LN; Figure 2l). Upon MC903 treatment, the induction of Th2 cytokines (IL4, IL13, IL10, IL6, and IL31) in WT LNs was not observed in TSLP / LNs, indicating that the MC903-triggered Th2 response is abolished in TSLP / mice. No change was seen for IFNg transcript levels in WT or TSLP / LNs, from either MC903or ethanol-treated mice, suggesting that MC903 application does not involve a Th1 response in LNs. In conclusion, we demonstrate unequivocally here that TSLP produced by keratinocytes is absolutely required in pathogenesis of AD triggered by topical application of the vitamin D3 analogue MC903. We also show that in this AD model, induction of IL4, IL13, IL31, and eotaxin-2 is fully TSLP dependent, whereas that of IL6, IL10, and monocyte chemotactic protein-2 is only partially TSLP dependent, and that of IFNg is TSLP independent. Finally, our floxed TSLP mice will be helpful for selective ablation of TSLP in other cell types (Soumelis and Liu, 2004; Ziegler and Liu, 2006; Holgate, 2007; Sokol et al., 2008), and therefore to further elucidate the physiological and pathological function of this cytokine.

Angioedema hereditário: considerações sobre terapia

PURPOSE: Hereditary Angioedema was first described by William Osler in 1888 and it is caused by a hereditary or acquired deficiency of C1 esterase inhibitor (C1-INH). Treatment is indicated for acute attacks or prophylaxis of angioedema which occur in the subcutaneous tissue respiratory or gastrointestinal tracts. Treatment includes attenuated androgens, inhibitors of kininogen or plasminogen, like tranexamic acid or e-aminocaproic acid and the administration of C1-INH concentrate. We describe the peculiarities of the treatment chosen for 10 patients (4 families) with HAE and their evolution. METHODS: Ten patients (1-38 years old) with HAE were diagnosed by clinical history and laboratory evaluation. The following tests were performed for the complement system: C1-INH, C4 and C3 levels and hemolytic assay (CH50 and APH50) for the classic and alternative pathways. Treatment was initiated considering severity of symptoms, age, gender and therapeutic response of the patient. RESULTS: Clinical evaluation showed: 4/10 patients with recurrent subcutaneous edema; 3/10 with previous laryngeal edema and 3/10 with sporadic symptoms. Different severity of symptoms was verified in the same family. The laboratory evaluation detected: low C1-INH levels (10/10); low serum C4 level (8/10); undetectable CH50 (3/10) and low CH50 levels (6/10); low APH50 levels (2/10). Six out of ten patients did not receive any specific treatment and 2 of them had high risk of asphyxia. One adolescent had been controlled with e-aminocaproic acid, one child had been changed from danazol to tranexamic acid, a 30 year old female patient had received oxandrolone and a 38 year old man had been treated with danazol. CONCLUSIONS: Although HAE is caused by the same defect and affects members of the same family, various approaches have been taken to treat these patients. We observed different alternatives of prophylactic therapy for HAE, of which some did not require drug therapy.

CD18 deficiency evolving to megakaryocytic (M7) acute myeloid leukemia: Case report

Leukocyte adhesion deficiency type 1 (LAD 1 - CD18 deficiency) is a rare disease characterized by disturbance of phagocyte function associated with less severe cellular and humoral dysfunction. The main features are bacterial and fungal infections predominantly in the skin and mucosal surfaces, impaired wound healing and delayed umbilical cord separation. The infections are indolent, necrotic and recurrent. In contrast to the striking difficulties in defense against bacterial and fungal microorganisms, LAD 1 patients do not exhibit susceptibility to viral infections and neoplasias. The severity of clinical manifestations is directly related to the degree of CD18 deficiency. Here, a 20 year-old female presenting a partial CD18 deficiency that developed a megakaryocytic (M7) acute myeloid leukemia is described for the first time. The clinical features of the patient included relapsing oral thrush due to Candida, cutaneous infections and upper and lower respiratory tract infections, followed by a locally severe necrotic genital herpetic lesion. The patients clinical features improved for a period of approximately two years, followed by severe bacterial infections. At that time, the investigation showed a megakaryocytic acute myeloid leukemia, treated with MEC without clinical improvement. The highly aggressive evolution of the leukemia in this patient suggests that adhesion molecules could be involved in the protection against the spread of neoplastic cells.

II Brazilian Consensus on the use of human immunoglobulin in patients with primary immunodeficiencies

RESUMO Nos ultimos anos, novas imunodeficiencias primarias e defeitos geneticos tem sido descritos. Recentemente, produtos de imunoglobulina, com aprimoramento em sua composicao e para uso por via subcutânea, tornaram-se disponiveis em nosso meio. Com o objetivo de orientar o medico no uso da imunoglobulina humana para o tratamento das imunodeficiencias primarias, os membros do Grupo de Assessoria em Imunodeficiencias da Associacao Brasileira de Alergia e Imunologia produziram um documento que teve por base uma revisao narrativa da literatura e sua [...]

Disseminated cryptococcosis manifested as a single tumor in an immunocompetent patient, similar to the cutaneous primary forms

Cryptococcosis is a fungal infection caused by Cryptococcus neoformans that tends to affect immunocompromised individuals. The fungi are mostly acquired by inhalation, which leads to an initial pulmonary infection. Later, other organs - such as the central nervous system and the skin - can be affected by hematogenous spread. In addition, cutaneous contamination can occur by primary inoculation after injuries (primary cutaneous cryptococcosis), whose diagnosis is defined based on the absence of systemic involvement. The clinical presentation of cutaneous forms typically vary according to the infection mode. We report an unusual case of disseminated cryptococcosis in an immunocompetent patient with cutaneous lesions similar to those caused by primary inoculation. This clinical picture leads us to question the definition of primary cutaneous cryptococcosis established in the literature.