Iranian Journal of Allergy, Asthma and Immunology
Volume:3 Issue: 4, Dec 2004

HIV infection by maternal transmission is increasing in the world due to the increase in infected women who are not receiving appropriate antiretroviral therapy. Prognosis of HIV infection in children is poor because the newborn has an immature immune system. Early diagnosis and therapy are needed to avoid the development of AIDS. New therapies are becoming available but prevention of infection, through maternal therapy during pregnancy, is the most effective measure in avoiding this infection through this transmission route.

Primary immunodeficiencies are rare diseases, characterized by an increased susceptibility to infections. Early diagnosis and appropriate treatment are critical for reducing morbidity and mortality. Given the rarity of these diseases, the awareness of these disorders by physicians is often insufficient, leading to delayed diagnosis and inappropriate treatment which are the major causes of severe long term complications. In an attempt to address and resolve these problems an Italian Network on primary immunodeficiencies has been established with the aim to increase the awareness of these disorders among physicians and to provide the best clinical assistance to all patients on the national territory.

There is interrelationship between the immune and nervous systems that is accomplished by the molecular mediators. Dopamine is one of the most important neurotransmitters. Five different dopamine receptor genes (DRD1, DRD2, DRD3, DRD4, and DRD5) have been recognized and cloned. The expression of the dopamine receptors is well characterized in the brain but little work has been done to examine their expression in other organ tissues. In certain diseases of the immune and nervous systems, alterations in dopamine receptors gene expression in different cells have been reported. This suggests that dopamine and its receptors have important role in pathophysiology of above-mentioned diseases.In the present study, using Real Time Polymerase Chain Reaction (PCR) technique, we investigated dopamine receptors genes expression in PBMC of normal individuals. The PBMC was separated from normal whole blood by Ficoll-hypaque; the total cellular RNA was then extracted and the cDNA was synthesized. This process followed by real time-PCR using primer pairs specific for five dopamine receptors mRNAs and β-actin as internal control. The results showed the presence of all types of dopamine receptors in lymphocytes of normal individuals. The specificities of the obtained PCR products for the respective dopamine receptors fragments were confirmed by sequenced analysis capillary system. In conclusion, the present study has shown that human lymphocytes express five dopamine receptors DR1-DR5. However, the conclusive evidence on the possible function of these receptors in lymphocytes remains unknown. Because lymphocytes express all of the five neuronal dopamine receptors, it is quite reasonable to consider them as a model of dopaminergic neuron.

X-linked agammaglobulinemia (XLA) is an immunodeficiency caused by mutations in the Bruton tyrosine kinase (Btk) gene. In order to identify the mutations in Btk gene in Iranian patients with antibody deficiency, 13 male patients with an XLA phenotype from 11 unrelated families were enrolled as the subjects of investigation for Btk mutation analysis using PCR-SSCP followed by sequencing. Five different mutations were identified in 5 patients from 5 unrelated families. Three mutations had been reported previously including TTTG deletion in intron 15 (4 bps upstream of exon 16 boundary), nonsense point mutation (1896G>A) that resulted in a premature stop codon (W588X) in kinase domain, and nucleotide alteration in invariant splice donor site of exon12 (IVS12+1G>A). While 2 novel missense mutations (2084A>G, 1783T>C) were identified leading to amino acid changes (I651T, Y551H). The results of this study further support the notion that molecular genetic testing represents an important tool for definitive and early diagnosis of XLA and may allow accurate carrier detection and prenatal diagnosis.

Non-enzymatic glycosylation of proteins is one of the key mechanisms in the pathogenesis of diabetic complications. Glycation of IgG is of special interest due to its possible influence on the functionality of immunoglobulins and overall immuno-competence. The aim of this study was to clarify more details of in vitro glycation of IgG and to study the effect of this modification on its interation with anti-IgG. Purified human IgG was glycated in the presence of 50 and 100 mM glucose. Glycation was measured using spectrophotometric thiobarbituric acid method. To study the effect of glycation on interaction with anti IgG the Single Radial Immunodiffusion (SRID) was used and the diameters of precipitation rings of glycated IgG and non-glycated IgG were measured and compared. The results showed that IgG was glycated in presence of 50 and 100 mM glucose at 27° and 37° C and the extent of glycation was dependent on glucose concentration and time of incubation. In higher concentration of glucose and longer period of incubation glycation was higher at 27° C (p<0.01). Similar results were obtained at 37° C.The results of SRID indicated that glycated IgG showed reduced interaction with anti-IgG. The diameters of precipitated rings for glycated IgG were significantly lower than those of non-glycated IgG (p < 0.01). It can be concluded that modification that occurred in IgG structure due to glycation can be the reason of the reduction of its interaction with anti-IgG.

Nutrition is an important factor that influences immunity, and nutritional deficiencies can impair resistance to infections. Malnutrition is the most common cause of immunodeficiency worldwide. Trace elements such as zinc, selenium, iron, and copper can influence several components of immunity. Primary antibody deficiency disorders are a group of disorders characterized by an unusual susceptibility to infections and malnutrition. Impaired nutritional status has been reported in immunodeficient patients. The aim of this study was to determine anthropometric indices and trace elements status in these patients. Thirty-eight children (28 males, 10 females, aged 2-18 years) with primary antibody deficiency referring to Children’s Medical Center of Tehran University of Medical Science were enrolled in this research. Primary immunodeficiency disorders consisting of CVID, XLA, IgA deficiency, IgG subclass deficiency, and hyper IgM were assessed. Anthropometric indices, comprised of height, weight that were measured and body mass index (BMI) was calculated. Height-for-age (HAZ), weight-for-height (WHZ) and weight-for-age (WAZ) were determined according to Z-score to study mild, moderate and severe malnutrition. Serum copper, zinc, selenium and iron levels were measured by an atomic absorption spectrometer. The most common disorders were CVID 52.5% and X-linked agammaglobulinaemia 27.5%. Based on BMI measurements 21.1% of patients had malnutrition. According to HAZ, 13.2%, 13.2% and 36.8% had severe, moderate and mild malnutrition, respectively. According to WAZ, 10.5%, 18.4% and 28.6% had severe, moderate and mild malnutrition, respectively. Regarding to WHZ, 14.3% and 28.6% had moderate and mild malnutrition, respectively. Low selenium levels and high copper levels were observed in 37.5% and 70.3%, respectively. Anthropometric data showed that the frequency of malnutrition in these patients was higher than the CDC standard. Low serum selenium levels and high serum copper levels were observed, suggesting further research is needed on these parameters. Most of the patients had serum zinc and iron levels within the normal range. It is recommeded that clinical immunologists and nutritionists should make a collective effort to provide these patients with standard or specialized diets so as to decrease the risk of infection.

The South eastern region of Iran is an endemic area for salmonellosis. Sometimes bacteremia due to nontyphoidal salmonella occurs but certain patients are at increased risk for recurrent bacteremia. The risk of invasive salmonellosis and recurrent bacteremia is increased in the patients with immunosuppression, especially impaired cell-mediated immunity, lymphoproliferative diseases and in patients with IL-12 deficiency. In recent years, a series of inherited disorders of IL-12-IFN-γ axis have been described that predispose affected individuals to disseminated disease caused by environmental mycobacteria and non-typhoidal salmonella. We report here the first such patient originating from and living in Iran. The patient was a 26-year-old man, suffering from IL-12p40 deficiency and presented with recurrent episodes of systemic salmonellosis. This report indicates that there are patients with inherited defects of the IL-12-IFN-γ circuit in Iran. We recommended to consider this group of disorders in all patients with recurrent non-typhoidal salmonella bacteremia, wherever they are found.

Acute renal failure is one of the side effects while using intravenous immunoglobulins. This complication is also observed with iodinated contrast media. Herein, we describe a patient with acute renal failure who received intravenous immunoglobulins and iodinated contrast media concomitantly. Both drugs are responsible for osmotic nephrosis. The same effect on renal cells may explain a synergistic effect on renal function.