Expansion of CMV-specific CD8+CD45RA+CD27- T cells in B-cell chronic lymphocytic leukemia

In patients with B-cell chronic lymphocytic leukemia (B-CLL), the absolute number of T cells is increased. Although it has been suggested that these T cells might be tumor specific, concrete evidence for this hypothesis is lacking. We performed a detailed immunophenotypic analysis of the T-cell compartment in the peripheral blood of 28 patients with B-CLL (Rai 0, n = 12; Rai I-II, n = 10; Rai III-IV, n = 6) and 12 healthy age-matched controls and measured the ability of these patients to mount specific immune responses. In all Rai stages a significant increase in the absolute numbers of CD3+ cells was observed. Whereas the number of CD4+ cells was not different from controls, patients with B-CLL showed significantly increased relative and absolute numbers of CD8+ cells, which exhibited a CD45RA+CD27- cytotoxic phenotype. Analysis of specific immune responses with tetrameric cytomegalovirus (CMV)-peptide complexes showed that patients with B-CLL had significantly increased numbers of tetramer-binding CMV-specific CD8+ T cells. The rise in the total number of CD8+ cytotoxic T cells was evident only in CMV-seropositive B-CLL patients. Thus, our data suggest that in patients with B-CLL the composition of T cells is shifted toward a CD8+ cytotoxic cell type in an effort to control infections with persistent viruses such as CMV. Moreover, they offer an explanation for the high incidence of CMV reactivation in CLL patients treated with T cell-depleting agents, such as the monoclonal antibody (mAb) alemtuzumab (Campath; alpha-CD52 mAb). Furthermore, because in CMV-seronegative patients no increase in cytotoxic CD8+ T cells is found, our studies do not support the hypothesis that tumor-specific T cells account for T-cell expansion in B-CLL.     

Immunomodulatory effects of L-carnitine and q10 in mouse spleen exposed to low-frequency high-intensity magnetic field

In the current study, we have investigated the bioeffects of repeated exposure to low-frequency (50 Hz) high-intensity (20 mT; 200 G) electromagnetic field (EMF) on some immune parameters in mice. The animals were exposed to EMF daily for 30 min three times per week for 2 weeks. We also studied the possible immunomodulatory effects of two anti-radical substances known to have non-specific immunostimulant effects namely, L-carnitine (200 mg/kg body weight i.p.) and Q10 (200 mg/kg body weight, p.o.). Both drugs were given 1 h prior to each EMF exposure. Immune endpoints included total body weight, spleen/body weight ratio, splenocytes viability, total and differential white blood cell (WBCs; lymphocytes, monocytes, neutrophils) counts, as well as the lymphocyte proliferation induced by the mitogens; phytohaemagglutinin (PHA), concanavalin-A (Con-A) and lipoploysaccharide (LPS). Magnetic field decreased splenocyte viability, WBCs count, as well as mitogens-induced lymphocyte proliferation. L-carnitine, but not Q10 could ameliorate the adverse effects of EMF on the vast majority of the immune parameters tested, suggesting a possible immunoprotective role of L-carnitine under the current experimental conditions.     

How many ganglion cells are there to a foveal cone?

Published studies on humans and monkeys show discrepancies in the reported quantitative relationship between cones (C) and ganglion cells (G). Data on human foveal retina suggest that it cannot accommodate the midget on-off system in addition to other functional channels. Foveal cell densities along the vertical meridian (0–1.8 mm eccentricity) were estimated in one normal human retina using the disector method. Cell ratios were calculated from cumulative total numbers. G density peaked at 0.65 mm eccentricity and C density at the foveola. Cumulative cell numbers showed a more rapid increase in G than in C with increasing eccentricity. G/C ratios of 2.7–3.4 were found using lateral displacement data modified from macaque. Using one estimate of displacement from the sections, the G/C ratio was 3.0. This study shows that there are on average three ganglion cells per foveal cone in humans, as in monkeys.     

Pulmonary artery “stop-flow” angiography to visualize the anomalous origin of the left coronary artery from the pulmonary artery in infants

Summary In five infants, anomalous left coronary from the pulmonary artery (ALCA) was diagnosed by selective pulmonary artery angiography using the “stop flow” technique: the left pulmonary artery was occluded by inflating a balloon and a large bolus of dye was injected proximal to the balloon at a high flow velocity. These conditions, by increasing pulmonary artery pressure, increase the chances of imaging directly an ALCA. It also leaves the left pulmonary artery branches free of contrast medium and allows easier visualization of ALCA, mainly in the antero-posterior view. When an ALCA is injected from the pulmonary artery, left heart catheterization can be avoided. However, a false-negative result is to be expected in specific conditions and was observed in one of our patients. If pulmonary angiography fails to prove a ALCA, left heart catheterization remains mandatory to exclude the diagnosis.     

The synergistic effect of adenosine A2A receptors agonist, type IV phosphodiestease inhibitor and ATP-sensitive K channels activation on free radicals production and aggregation of human polymorphoneuclear leukocytes.

The adenosine A2A receptor agonist CGS21680 (50, 100 and 200 microg/ml), the phosphodiserease type IV (PDE IV) inhibitor Rolipram (50, 100 and 200 microg/ml) and, ATP-sensitive K+ channels activator Cromakalim (30 and 40 microg/ml), when added separately, inhibit oxygen free radicals production from isolated human polymorphoneuclear leukocytes (PMNLs), stimulated with phorbol myristate acetate (PMA), in a dose dependent manner. When both CGS21680 and Rolipram were combined, in vitro, the inhibitory effect on PMNLs free radicals production was synergistic. On the other hand, when both the ATP-sensitive K+ channels opener (KATP) Cromakalim and the type IV PDE inhibitor Rolipram were combined, produced negative synergism (the inhibitory effect of both drugs disappeared). Furthermore, CGS21680, Rolipram, Cromakalim and Forskolin produced no significant inhibitory effect on PMNLs aggregation when added separately. But when various combinations of the above drugs were used, produced significant inhibition of aggregation. Only CGS21680 exhibited a scavenging effect on free radicals production. From the above results, combination of adenosine A2A agonists and type IV PDE inhibitors could serve as potentially novel anti-inflammatory drugs. Furthermore, ATP-sensitive K+ channels activators should be considered for further investigation as anti-inflammatory drug.     

Properties of CD4(+) T cells in human cytomegalovirus infection

The correlates of protective immunity to disease-inducing viruses in man remain to be elucidated. We determined the kinetics and properties of cytomegalovirus (CMV)-specific CD4(+) T cells in healthy individuals and renal transplant recipients during different stages of CMV infection. Our data reveal that circulating CMV-specific CD4(+) T cells displayed an effector-memory phenotype, and produced the T helper 1 cytokines interferon-gamma and tumor necrosis factor-alpha. In addition, they lacked molecules for secondary lymphoid organ homing and expressed the cytotoxic molecule granzyme B, inferring a direct role of these cells at target sites of infection. In asymptomatic individuals the CMV-specific CD4(+) T-cell response preceded CMV-specific CD8(+) T-cell responses, whereas in symptomatic individuals the CMV-specific effector memory CD4(+) T-cell response was delayed and only detectable after antiviral therapy. The appearance of disease symptoms in these patients suggests that functional CD8(+) T cell and antibody responses are insufficient to control viral replication and that formation of effector memory CD4(+) T cells is necessary for recovery of infection.     

Longevity of Middle East Respiratory Syndrome Coronavirus Antibody Responses in Humans,Saudi Arabia

Understanding the immune response to Middle East respiratory syndrome coronavirus (MERS-CoV) is crucial for disease prevention and vaccine development. We studied the antibody responses in 48 human MERS-CoV infection survivors who had variable disease severity in Saudi Arabia. MERS-CoV–specific neutralizing antibodies were detected for 6 years postinfection.     

Pediatric Gastrointestinal Sarcoidosis: Successful Treatment with Infliximab

Gastrointestinal sarcoidosis is a rare disease with very limited data in children. Here we report the first pediatric case of successful treatment with infliximab. The first case was an 8-year-old Saudi girl who presented with fever, weight loss, and abdominal pain that was followed in a few months with hematemesis and development of hepatosplenomegaly. The second case was a 9-year-old Sudanese boy who manifested with vomiting, epigastric pain, and weight loss. On upper endoscopy, both cases demonstrated severe erosive nodular gastric mucosa. Gastric and esophageal biopsies had shown noncaseating granulomatous inflammation. The first case had histopathological evidence of granulomatous hepatitis, and both cases demonstrated lung nodularity on computed tomography chest. The boy had elevated angiotensin-converting enzyme level. Given the multisystem involvement with significant chest findings, tissue findings of granulomatous disease, and negative workup for other causes of granulomatous inflammation, both cases were diagnosed with active disseminated sarcoidosis, and treated with corticosteroids. The girl continued to be symptom-free for 4 years after tapering steroid therapy. The boy had relapses off steroids and the disease was brought into remission for 5 years off steroid therapy by infliximab. Pediatric GI sarcoidosis is a rare disease that exhibits heterogeneity in natural course. The chronic relapsing progressive form of the disease might benefit from infliximab therapy.Key Words: Atrophic gastritis, children, gastrointestinal sarcoidosis, infliximab, Vitamin B12 deficiencySarcoidosis is a multiorgan systemic disease characterized by the formation of non-necrotizing epithelioid granulomas in the affected organs, including skin, lungs, heart, nervous system, hilar lymph nodes, liver, eyes, and joints. Sarcoidosis occurs mainly in the 20- to 40-year-old age group. The prevalence is reported to be 1–40 per 100,000 in the United States.[1] Sarcoidosis of the gastrointestinal tract (GIT) is reported to be extremely rare. Several autopsy studies found no GI involvement,[2] while another reported gastrointestinal involvement in 2.5%.[2] In contrast, liver follows lymph nodes and lung in the frequency of involvement. About 50%–79% of livers are involved by biopsy and 67–70% by autopsy.[2] Treatment with corticosteroids results in symptomatic improvement in majority of patients. Other steroid-sparing agents that had been used in steroid-dependent or -resistant cases included chloroquine, azathioprine, methotrexate, and cyclophosphamide. Infliximab has been shown to produce clinical improvement and reduce the requirement for corticosteroids in a very small number of adult patients with sarcoidosis.[3]We report two children with gastrointestinal (GI) sarcoidosis, added to the four cases of GI sarcoidosis already reported in the pediatric literature, and report the first pediatric case of successful treatment with infliximab.     

The levels of blood mercury and inflammatory-related neuropeptides in the serum are correlated in children with autism spectrum disorder

Tachykinins (substance P, neurokinin A, and neurokinin B) are pro-inflammatory neuropeptides that may play an important role in some autoimmune neuroinflammatory diseases, including autism spectrum disorder (ASD). Mercury (Hg) is a neurotoxicant, and potentially one of the main environmental triggers for ASD as it induces neuroinflammation with a subsequent release of neuropeptides. This is the first study to explore the potentially causal relationship between levels of serum neurokinin A and blood mercury (BHg) in children with ASD. Levels of serum neurokinin A and BHg were measured in 84 children with ASD, aged between 3 and 10 years, and 84 healthy-matched children. There was a positive linear relationship between the Childhood Autism Rating Scale (CARS) and both serum neurokinin A and BHg. ASD children had significantly higher levels of serum neurokinin A than healthy controls (P?<?0.001). Increased levels of serum neurokinin A and BHg were respectively found in 54.8 % and 42.9 % of the two groups. There was significant and positive linear relationship between levels of serum neurokinin A and BHg in children with moderate and severe ASD, but not in healthy control children. It was found that 78.3 % of the ASD patients with increased serum levels of neurokinin A had elevated BHg levels (P?<?0.001). Neuroinflammation, with increased levels of neurokinin A, is seen in some children with ASD, and may be caused by elevated BHg levels. Further research is recommended to determine the pathogenic role of increased levels of serum neurokinin A and BHg in ASD. The therapeutic role of tachykinin receptor antagonists, a potential new class of anti-inflammatory medications, and Hg chelators, should also be studied in ASD.     

The positive association between elevated blood lead levels and brain-specific autoantibodies in autistic children from low lead-polluted areas

The underlying pathogenic mechanism in autoimmune disorders is the formation of autoantibodies. In children with autism spectrum disorder (ASD), it has been documented increased levels of brain-specific autoantibodies. Furthermore, lead (Pb) has been identified as one of the main neurotoxicants acting as environmental triggers for ASD as it induces neuroinflammation and autoimmunity. The present study is the first to explore a potential relationship between the levels of blood lead (BPb) and seropositivity of anti-ribosomal P protein antibodies in ASD children. Levels of BPb and serum anti-ribosomal P protein antibodies were measured in 60 children with ASD and 60 healthy control matched children, aged between 5 and 12 years, recruited from low Pb-polluted areas. The levels of BPb were significantly higher in ASD children than in healthy control children (P < 0.001). Patients with ASD had significantly higher frequency of increased BPb levels ≥10 μg/dL (43.3 %) than healthy control children (13.3 %; P < 0.001). There were significant and positive correlations between the levels of BPb, and the values of Childhood Autism Rating Scale (CARS) (P < 0.01) and IQ in children with ASD (P < 0.001). Patients with ASD showing increased levels of BPb had significantly higher frequency of seropositivity of anti-ribosomal P antibodies (92.3 %) than patients with normal BPb levels (32.3 %; P < 0.001). The findings of the present study suggest that increased levels of BPb in some children with ASD may trigger the production of serum anti-ribosomal P antibodies. Further research is warranted to determine if the production of brain autoantibodies is triggered by environmental Pb exposure in children with ASD. The possible therapeutic role of Pb chelators in ASD children should also be studied.