Iranian Journal of Allergy, Asthma and Immunology
Volume:7 Issue: 2, Jun 2008

Bacterial protein toxins have been exploited as therapeutic agents and as vaccines. An issue of deserving interest is development of new generations of vaccines and immune adjuvants. In this study an active assembled recombinant Shiga toxin of Escherichia coli (rStx1) and its derivatives, recombinant A and B subunits (Stx1-A and Stx1-B), were used to immunize mice. The elicited antibody responses were compared with and without using adjuvant. Protection against intraperitoneal lethal dose of rStx challenge was observed by immunization with sublethal dose of rStx1, rStx-A and rStx-B subunits. The immunological studies on toxin subunits can be used for immunization against systemic shiga toxin mediated disease and also subunits as a vector for antigen presentation in immunotherapeutic approaches. In our experiment, while stimulation of the immune system by A and B subunits were different, both subunits produced neutralizing antibodies. Regarding B subunit the amount of specific IgG1/IgG2a antibody ratio was higher than A subunit. In addition B subunit stimulated proliferation of immune cells with IFNg production the same as rStx1, suggesting that B subunit can be used as an immunomodulator to stimulate the immune response in conjunction with other recombinant proteins.

Stromal derived factor-α (SDF-1-α) is a CXC chemokine which has been demonstrated as a recruitment factor for leukocytes to the site of inflammation, infection, injury and following stress. This chemokine has been shown to be expressed by liver cells and in liver diseases. Hence, the aim of this study was to examine the expression of SDF-1 by hepatocytes in responses to the stress imposed during isolation by collagenase perfusion and under heat shock stimulation. In this study hepatocytes (2-5 x 106) were isolated from male Sprague Dawley rat liver and cultured in plates that were pre-coated with collagen Type-I matrix. The western and northern blotting analysis were employed to detect SDF-1 at protein and mRNA levels in isolated and cultured hepatocytes in response to isolation and heat shock stressesThe SDF-1 is expressed by isolated rat hepatocytes immediately after isolation and early culture and decreased with time. SDF-1 protein was highly expressed in freshly isolated cells and decreased by time (27h) (P<0.05). mRNA was also expressed in freshly isolated cells (0h) but decreased after 24h of culture (P<0.01). This results also demonstrated that expression of SDF-1 by hepatocytes was increased in response to heat shock at different time points comparing with control (P<0.01). These results demonstrated that the isolation and heat shock stresses induced the expression of SDF-1 in hepatocytes in a time-dependent manner. Accordingly, it seems that hepatocytes mimic the experiences that liver experience after injury in vivo and therefore, produce stress related agents like chemokines to overcome such a injurious condition.

Bronchiectasis is a chronic debilitating condition characterized by abnormal dilated thick-walled bronchi. To investigate humoral immune function in bronchiectatic patients, this study was performed. Forty patients with established diagnosis of bronchiectasis, who were referred from two tertiary care pulmonology centers in Tehran, were investigated in this study. Immunoglobulin isotypes concentrations and IgG-subclasses were measured by nephelometry and enzyme-linked immunosorbent assay (ELISA) methods, respectively. All patients received unconjugated pneumococcal vaccine, and blood samples were taken before and 21 days after vaccination. Specific antibodies against whole pneumococcal antigens were measured using the ELISA method. Fifteen (37.5%) out of 40 patients were diagnosed to have defects in antibody mediated immunity including 5 (12.5%) patients with immunoglobulin class deficiency (2 with common variable immunodeficiency and 3 with IgA deficiency), 3 (7.5%) with IgG subclass deficiency and 7 (17.5%) patients had Specific antibody deficiency (SAD) against polysaccharide antigen despite normal levels of serum immunoglobulins and IgG subclasses.Our study along with several other studies confirmed that all patients with bronchiectasis should undergo thorough immunological evaluation in order to identify the presence of the underlying immunologic defect. This evaluation should include serum immunoglobulins, IgG subclasses concentrations and also determination of serum antibodies against pneumococcal antigens. Early diagnosis and appropriate treatment will prevent the subsequent complications and improve quality of life of affected individuals.

Hypoxia and hypocapnia can cause broncho-constriction in human subjects, and this could have a bearing on performance at high altitude. The object of this study was to examine how pulmonary ventilatory functions during high-altitude trekking. This study is a cohort study on spirometric parameters at different altitudes. Fifty six healthy male volunteers from a university student population were enrolled in the study (ages 22.9±5.3 years). Pulmonary function was assessed with a Spirolab II in all participants before ascending at baseline (1150 meter), after ascending at different altitudes (2850, 4150 meter), and after descending at sea level during a 3-day trek in Sialan Mount. This study indicates that in an actual trek, ascending results in significant decrease in forced vital capacity (FVC). FVC significantly decreased with increasing altitude from baseline level and at the sea level it was significantly less than baseline level. Peak flow increased with increasing altitude from baseline (1150 m) to 2850 m and decreased with decreasing altitude (p<0.01). Maximal midexpiratory flow rate (FEF 25-75%) and forced expiratory volume in 1 second to forced expiratory volume ratio (FEV1.0%) significantly increased with increasing and decreasing altitude from baseline level (p<0.001). There was no significant change in FEV1. It could be concluded that changes in some pulmonary ventilatory parameters were proportional to the magnitude of change in altitude during a high-altitude trek. These changes are significant at the beginning of ascending.

Asthma is one of the most common acute and chronic conditions in children, and the pediatricians are expected to provide an important role for asthma care in this age group, however there is no published information describing the different aspects of their practices about children asthma in Iran. This study was done to characterize the knowledge of the Iranian pediatricians about the diagnosis, treatment and education of asthma in children. Validated questionnaires were completed by 193 pediatricians from different parts of Iran during the International Congress of Pediatrics in Tehran. A total of 193 returned questionnaires (96.5%) were eligible for the survey and analysis. About 49% of the respondents were male and 18% were sub-specialists. Wheezing was the most common mentioned symptoms in taking asthma into consideration. About 40% of these physicians had no plan for doing spirometry in eligible children and 35.2% of them did not have familiarity with peak flowmeter. Also about 17.6% of them paid no regular visits to their asthmatic patients. Only 29% of the respondents indicated that they would prescribe inhaled corticosteroids for a 6-year-old child with moderate persistent asthma and 73.3% of them would prescribe inhaled bronchodilator (Salbutamol) for an acute asthmatic attack as the first drug, while 17.1% of them used epinephrine injection for this purpose. About 42.2% of the respondents did not consider any education or action plan for their patients and only 60.6% of them had access to standard guidelines and educational programs. The results show that there are numerous aspects of children asthma management in Iran which are not consistent with standardized guidelines and recommendations. This survey and the attained information suggest areas for interventions to improve the pediatricians’ knowledge about asthma and the disease management.

Systemic lupus erythematosus (SLE) is an autoimmune disease in which polymorphisms within the human leukocyte antigen (HLA) region have been associated to its etiology. We conducted this study to compare the HLA-DQB1 allelic sequence variation among SLE patients and controls in the northeast of Iran. Genomic DNA of 40 SLE patients and 83 healthy controls were amplified by Polymerase Chain Reaction with Sequence-Specific Primers technique (PCR-SSP). Seven serological subclasses of the HLA DQB1 were detected. Allele distribution comparison showed in the SLE group a significant increase of HLA DQ6 (*0601-*0609) (p=0.006); whereas alleles HLA DQ7 (*0301-*0304) were significantly decreased (p=0.005). Combination of DQ5 (*0501-*0504)-DQ6 (*0601-*0609) was increased in patients. These results suggest that DQ6 is the dominant HLA DQB1 allele probably associated with genetic susceptibility to SLE in the northeast of Iran. The association supports the importance of ethnic background and indicates the importance of various genes that has been observed in different SLE populations.

Natural rubber latex is the second most implicated agent in intraoperative anaphylactic reactions. This report describes a case of intraoperative anaphylaxis occurring in a non-atopic fourteen-year-old girl undergoing multiple surgical procedures, but without spina bifida, in which latex surgical gloves were the main culprit for the anaphylactic reactions. Clinical manifestations of an anaphylactic reaction were also experienced during the examination of the possible cause of intraoperative anaphylaxis by skin prick testing with a latex allergen extract. Skin tests with anesthetics were negative. Specific IgE to latex was positive at 92.9 kUA/L (class 5). The molecular basis for the reported intraoperative anaphylaxis was ascribed to three low-molecular mass latex allergens (10-15 kD) detected in the brand of latex surgical gloves used during the operation. Given the potential of a dramatic outcome, latex allergy testing as a regular preoperative measure may contribute to the reduction of anaphylactic reactions during surgical interventions

Hyper-immunoglobulin E syndrome is a rare primary immunodeficiency disease characterized by recurrent abscess formation, respiratory tract infections and very high titers of serum IgE associated with peculiar face and skeletal features. We report a seven-year old girl presenting with persistent productive cough and history of chronic eczematoid facial lesions since infancy and two episodes of hospitalizations due to pneumonia and perianal abscess. Additionally, in physical examination finger tip clubbing, laxity of joints and crackles in both lungs were detected. Immunologic work up revealed markedly raised IgE level and eosinophilia. The patient was diagnosed as hyper IgE syndrome based on his clinical and laboratory findings. Chest X-ray revealed multiple large cystic lesions in left lung which were confirmed by spiral CT-scan. Pneumonectomy specimen examination showed cystic adenomatoid malformation, characterized by the presence of various cysts lined by epithelium in different sizes. There are few reports of cystic adenomatoid malformation in children. To our best known, this is the first report of cystic adenomatoid malformation in a child with hyper IgE syndrome. Early diagnosis and surgical therapy are helpful in prevention of repeated infections in these patients.

Asthma is considered to be the most common respiratory disorder complicating pregnancy. Seventy-six asthmatic and 152 non-asthmatic pregnant women were studied. Maternal asthma was significantly associated with adverse infant outcomes, including prematurity, low birth weight and the need for Cesarean delivery. The results of this study could indicate that pregnant women with asthma were at substantially increased risk for adverse infant outcomes and suggest the need for extra attention to mothers with asthma before and during pregnancy