Relationship between serum and saliva antibodies to Candida and isolation of Candida species from the mucosa of HIV-infected individuals

Colonisation and infection by Candida species occur frequently in acquired immunodeficiency syndrome (AIDS), but their relationship to the humoral immunity against candidiasis is controversial. To evaluate the levels of antibodies to Candida in the serum and in the saliva of HIV-1-infected patients in relation to the presence of immunodeficiency, oral candidiasis and Candida colonisation, Candida was investigated in the urine and in the oral and anal mucosae of HIV-1-infected patients, AIDS patients and healthy controls. The levels of IgG, IgM and IgA antibodies to Candida were determined in the serum and in the saliva by immunoassay. Candida species were detected in 76% of the patients. Mucosal yeast colonisation and the levels of serum and saliva antibodies to Candida were similar between asymptomatic HIV-infected and non-infected patients. Mucosal colonisation was highest in AIDS patients, who also had higher serum IgA and saliva IgG antibodies. Antibody levels were similar in patients with and without candidiasis oral lesions. Asymptomatic HIV-infected individuals are similar to non-infected individuals with respect to mucosal colonisation as well as serum and saliva levels of antibodies to Candida. The higher mucosal colonisation and clinical candidiasis observed in the AIDS patients apparently stimulated a more intense humoral response to the yeast.

Anti-nucleosome and anti-chromatin antibodies are present in active systemic lupus erythematosus but not in the cutaneous form of the disease

The objective of this study is to investigate the presence of anti-nucleosome (anti-NCS) and anti-chromatin (anti-CRT) antibodies in patients with cutaneous lupus erythematosus (CLE) compared with active and inactive systemic lupus erythematosus (SLE). A total of 154 subjects were evaluated: 54 patients presenting CLE, 66 patients with active SLE and 34 with inactive SLE. Lupus activity was assessed using the disease activity index (SLEDAI). Anti-NCS and anti-CRT antibodies were detected by enzyme-linked immunosorbent assay ( ELISA). Only one of 54 patients with CLE tested positive for both anti-NCS and anti-CRT antibodies. The prevalence of anti-CRT antibodies was significantly higher in active SLE (84.8%) when compared with inactive SLE (26.4%) and CLE (1.8%) ( P < 0.001). Anti-NCS antibodies were also more prevalent in active SLE patients (74.2%) than inactive SLE (11.7%) and CLE patients ( 1.8%) ( P < 0.001). The presence of anti-CRT and anti-NCS antibodies was correlated to disease activity in patients with SLE (r = 0.4937, r = 0.5621, respectively). Furthermore, the detection of both antibodies was correlated with disease activity in patients with SLE who tested negative for anti-dsDNA antibodies ( r = 0.4754 for anti-NCS and r = 0.4281 for anti-CRT). The presence of these two auto-antibodies was strongly associated with renal damage in patients with SLE ( OR = 13.1, for anti-CRT antibodies and OR = 25.83, for anti-NCS antibodies). The anti-NCS and anti-CRT antibodies were not found in CLE. In patients with SLE, there is a correlation of these antibodies with disease activity and active nephritis. When compared with anti-dsDNA antibodies, anti-NCS and anti-CRT antibodies were more sensitive in detecting disease activity and kidney damage in lupus patients. Lupus (2009) 18, 223-229.

Efficiency of the DNA repair and polymorphisms of the XRCC1, XRCC3 and XRCC4 DNA repair genes in systemic lupus erythematosus

Impaired DNA repair efficiency in systematic lupus erythematosus (SLE) patients has been reported ill some studies, mainly regarding the repair of oxidative damage, but little is known about repair kinetics towards primarily single-stranded DNA breaks. In the present study, we aimed to investigate: (a) the efficiency of SLE peripheral blood leucocytes in repairing DNA damage induced by ionizing radiation and (b) the association of DNA repair gene (XRCC1 Arg399Gln, XRCC3 Thr241Met and XRCC4 Ile401Thr) polymorphisms in SLE patients, considering the whole group, or stratified sub-groups according to clinical and laboratory features. A total of 163 SLE patients and 125 healthy control were studied. The kinetics of DNA strand break repair was evaluated by the comet assay, and genotyping for DNA repair genes was performed by PCR-RFLP. Compared with controls. SLE leucocytes exhibited decreased efficiency of DNA repair evaluated at 30 min following irradiation. A significant association with DNA repair gene polymorphisms was not observed for the whole group of SLE patients; however, the XRCC1Arg399Gln polymorphism was associated with the presence of anti-dsDNA antibody. The concomitance of two DNA repair polymorphic sites was associated with the presence of neuropsychiatric manifestations and antiphospholipid antibody syndrome. Taken together, these results indicated that SLE leucocytes repair less efficiently the radiation-induced DNA damage, and DNA repair polymorphic sites may predispose to the development of particular clinical and laboratory features. Lupus (2008) 17, 988-995.

Measurement of IgE antibodies to shrimp tropomyosin is superior to skin prick testing with commercial extract and measurement of IgE to shrimp for predicting clinically relevant allergic reactions after shrimp ingestion

Background: Shrimp is a frequent cause of food allergy. Tropomyosin is the major allergen in shrimp, and it shares homology to tropomyosins from other crustaceans, dust mites, cockroach, and parasites. Objective: The aim of this study was to determine the value of detection of IgE to shrimp tropomyosin in the diagnosis of shrimp allergy. Methods: We have studied 35 patients with asthma, rhinitis, or both who were sensitized to Dermatophagoides pteronyssinus. All subjects underwent skin prick testing in addition to double-blind, placebo-controlled food challenges (DBPCFC); oral open challenges; or both with shrimp. Measurements of IgE to shrimp and shrimp tropomyosin were carried out by means of CAP and chimeric ELISA, respectively. Results: Oral challenges confirmed the diagnosis of shrimp allergy in 7 patients. IgE measurement to shrimp tropomyosin was positive in 71.4% of the patients with shrimp allergy. Of the 28 patients without shrimp allergy, only 7.1% (2/28) had IgE to shrimp tropomyosin compared with 25% (7/28) who had IgE to shrimp and 35.7% (10/28) who had positive skin prick test responses to shrimp. Sensitivity was similar for all 3 methods (71.4%); in contrast, specificity of IgE to shrimp tropomyosin (92.8%) was greater than that of IgE to shrimp (75%) and skin prick testing (64.2%). With regard to diagnostic efficiency, measurement of IgE to shrimp tropomyosin was superior to measurement of IgE to shrimp and skin prick testing (88.5%, 74.2%, and 65.7%, respectively). Conclusion: Use of measurements of IgE to shrimp tropomyosin provided added value to the diagnosis of shrimp allergy. (J Allergy Clin Immunol 2010;125:872-8.)

Ultrasonography in pregnant women with antiphospholipid syndrome using salicylic acid and heparin

The objective of the present study was to evaluate fetal biometry, Doppler values, and perinatal outcomes in pregnant women with antiphospholipid syndrome treated with acetylsalicylic acid and heparin. Twenty-five pregnant women with antiphospholipid syndrome using 100 mg/day acetylsalicylic acid and 5,000 IU heparin every 12 h were evaluated in this prospective observational study. Ultrasonography was performed between 24 and 38 weeks of gestational age to assess estimated fetal weight, placental thickness, amniotic fluid index, fetal biophysical profile and Doppler evaluation of maternal uterine arteries, and fetal middle cerebral and umbilical arteries. Data regarding Apgar score, gender, delivery mode, and birth weight and length were recorded after birth. The observed values for ultrasonographic assessment and perinatal outcomes were not very different from the expected values for normal pregnancies. The birth weight was 2863.3 +/- A 737.7 g (mean +/- A SD) and length was 46.8 +/- A 4.2 cm. Only one newborn (4%) had the 1-min Apgar score < 7 and all had the 5-min Apgar score > 7. Gestational and perinatal evaluation of pregnant women with antiphospholipid syndrome using both acetylsalicylic acid and heparin was reassuring.

A Dynamical Modeling to Study the Adaptive Immune System and the Influence of Antibodies in the Immune Memory

Immunological systems have been an abundant inspiration to contemporary computer scientists. Problem solving strategies, stemming from known immune system phenomena, have been successfully applied to chall enging problems of modem computing. Simulation systems and mathematical modeling are also beginning use to answer more complex immunological questions as immune memory process and duration of vaccines, where the regulation mechanisms are not still known sufficiently (Lundegaard, Lund, Kesmir, Brunak, Nielsen, 2007). In this article we studied in machina a approach to simulate the process of antigenic mutation and its implications for the process of memory. Our results have suggested that the durability of the immune memory is affected by the process of antigenic mutation.and by populations of soluble antibodies in the blood. The results also strongly suggest that the decrease of the production of antibodies favors the global maintenance of immune memory.

A DNA vaccine candidate expressing dengue-3 virus prM and E proteins elicits neutralizing antibodies and protects mice against lethal challenge

In an effort to develop a suitable DNA vaccine candidate for dengue, using dengue-3 virus (DENV-3) as a prototype, the genes coding for premembrane (prM) and envelope proteins (E) were inserted into an expression plasmid. After selecting recombinant clones containing prM/E genes, protein expression in the cell monolayer was detected by indirect immunofluorescence and immunoprecipitation assays. After selecting three vaccine candidates (pVAC1DEN3, pVAC2DEN3 and pVAC3DEN3), they were analyzed in vivo to determine their ability to induce a DENV-3-specific immune response. After three immunizations, the spleens of the immunized animals were isolated, and the cells were cultivated to measure cytokine levels by ELISA and used for lymphoproliferation assays. All of the animals inoculated with the recombinant clones induced neutralizing antibodies against DENV-3 and produced a T cell proliferation response after specific stimuli. Immunized and control mice were challenged with a lethal dose of DENV-3 and observed in order to assess their survival capability. The groups that presented the best survival rate after the challenge were the animals vaccinated with the pVAC3DEN3 clones, with an 80% survival rate. Thus, these data show that we have manufactured a vaccine candidate for DENV-3 that is able to induce a specific immune response and protects mice against a lethal challenge.

Generation of Polyclonal Antibodies Against Recombinant Human Glucocerebrosidase Produced in Escherichia coli

Deficiency of the lysosomal glucocerebrosidase (GCR) enzyme results in Gaucher`s disease, the most common inherited storage disorder. Treatment consists of enzyme replacement therapy by the administration of recombinant GCR produced in Chinese hamster ovary cells. The production of anti-GCR antibodies has already been described with placenta-derived human GCR that requires successive chromatographic procedures. Here, we report a practical and efficient method to obtain anti-GCR polyclonal antibodies against recombinant GCR produced in Escherichia coli and further purified by a single step through nickel affinity chromatography. The purified GCR was used to immunize BALB/c mice and the induction of anti-GCR antibodies was evaluated by enzyme-linked immunosorbent assay. The specificity of the antiserum was also evaluated by western blot analysis against recombinant GCR produced by COS-7 cells or against endogenous GCR of human cell lines. GCR was strongly recognized by the produced antibodies, either as cell-associated or as secreted forms. The detected molecular masses of 59-66 kDa are in accordance to the expected size for glycosylated GCR. The GCR produced in E. coli would facilitate the production of polyclonal (shown here) and monoclonal antibodies and their use in the characterization of new biosimilar recombinant GCRs coming in the near future.

Prevalence of Rickettsia species antibodies and Rickettsia species DNA in the blood of cats with and without fever

Rickettsia species antibodies have been detected in some cats but it is unknown whether infected cats develop clinical signs. The prevalence of Rickettsia species deoxyribonucleic acid (DNA) in blood from clinically ill cats has not been determined. The objective of this study was to determine if cats with fever (body temperature >= 102.5 degrees F [39.2 degrees C]) were more likely to have evidence of rickettsial infection than healthy, age-matched, control cats with a body temperature < 102.5 degrees F. Rickettsia species polymerase chain reaction (PCR) assays were performed to detect rickettsial DNA extracted from blood (71 paired samples), indirect immunofluorescence assays (IFA) were performed to detect serum antibodies against Rickettsia felis (90 paired samples) and Rickettsia rickettsii (91 paired samples), and the results between pairs were compared. All samples were negative for Rickettsia species DNA. More cats with fever were seropositive for R felis or R rickettsii than control cats, but results were not statistically significant. Results of this pilot study failed to show an association between Rickettsia species DNA or Rickettsia species antibodies and fever. (c) 2008 ESFM and AAFP. Published by Elsevier Ltd. All rights reserved.

Prevalence of anti-Toxoplasma gondii and anti-Neospora caninum antibodies in sheep from Mossoro, Rio Grande do Norte, Brazil

Toxoplasma gondii is an obligate intracellular parasite with a variety of hosts, responsible for reproductive problems and economic losses in sheep flocks. Neospora caninum was recently identified and its clinical presentation in sheep is similar to that of toxoplasmosis, which can cause repeated abortions, though less frequently in this species. In order to confirm the prevalence of these agents in the city of Mossoro, Rio Grande do Norte, Brazil, 409 serum samples from adult sheep (364 females and 45 males) were tested by the indirect immunofluorescence antibody test, using cut-off point at a dilution of 1:64 and 1:50 for T. gondii and N. caninum, respectively. From the 35 properties examined, 23 (65.7%)had at least one seropositive animal for T gondii and six (17.1%) for N. caninum. The prevalence of seropositive animals for T. gondii was 20.7% and for N. caninum 1.8%. There was no association between the presence of the agent`s antibody and gender, reports of reproductive problems and presence of dogs and/or cats in the properties. T. gondii is well distributed and N. caninum has low prevalence in sheep and in the properties of the studied region. (C) 2008 Elsevier B.V. All rights reserved.

Evaluation of IFA, MAT, ELISAs and immunoblotting for the detection of anti-Toxoplasma gondii antibodies in paired serum and aqueous humour samples from experimentally infected pigs

The study evaluated the efficiency of diagnostic laboratory methods to detect anti-Toxoplasma gondii antibodies in paired serum and aqueous humour samples from experimentally infected pigs. 18-mixed breed pigs were used during the experiment; these were divided into two groups, G I (infected group, n = 10) and G2 (uninfected group, n = 8). Infection was performed with 4 x 10(4) VEG strain oocysts at day 0 by the oral route in G1 animals. All pigs were euthanized at day 60, when retina, aqueous humour, and blood samples were collected. Anti-T gondii antibody levels were assessed in serum (s) and aqueous humour (ah) by indirect immunofluorescence assay (IFA), modified agglutination test (MAT), m-ELISA (using crude membranes from T gondii tachyzoites as antigen) and r-ELISA (using rhoptries from T gondii tachyzoites as antigen). Polymerase chain reactions (PCR) of samples from the retina were performed by using Tox4 and Tox5 primers. Antibody titers of G1 animals ranged from 128 to 1024 and from 16 to 256 in serum and aqueous humour, respectively. There were differences in the correlation coefficients between IFA(s) x IFA (ah) (r = 0.62, P = 0.05), MAT(s) x MAT (ah) (r = 0.97, P < 0.0001); however, there was no significant difference between r-ELISA(s) x r-ELISA (ah) (r = 0. 14, P = 0.7). Antibodies present in serum and aqueous humour recognized similar antigens. Samples of retina were positive by PCR in 30% (3/10) of infected pigs. G2 animals remained without antibody levels and were PCR negative throughout the experiment. These results suggest that the use of a combination of tests and immunoblotting for paired aqueous humour and serum samples could improve the sensitivity and specificity for the diagnosis of ocular toxoplasmosis. (c) 2007 Elsevier Ltd. All rights reserved.

Prevalence of Neospora caninum antibodies in cattle from Santarem, Para, Brazil

Prevalence of anti-Neospora caninum antibodies was measured in serum samples randomly collected from dairy (40 cows from four farms) and beef cattle (120 animals from 12 farms) from the municipality of Santarem, Para State, Brazil, calculated by using the Win Episcope 2.0 statistical program. The presence of anti-N. caninum antibodies was determined by indirect immunofluorescence-antibody test with a cut-off value of 1: 100. We found that 13 farms (81.25%) showed infection rates above 10%, which indicates widespread distribution of M caninum in the region. The frequency per animal was 19%. No difference was observed between the prevalence values in dairy and beef animals or between farms, which was probably due to the small number of dairy farms examined. The results confirm, for the first time, the presence of anti-N. caninum antibodies in cattle from Para State and the necessity to further investigate the epidemiology of M caninum in the Amazon region. (c) 2007 Elsevier Ltd. All rights reserved.

Detection of Rabies Virus Antibodies in Brazilian Free-Ranging Wild Carnivores

Rabies virus is a pathogen of major concern in free-ranging wild carnivores in several regions of the world, but little is known about its circulation in Brazilian wild carnivores. Sera from 211 free-ranging wild carnivores, captured from 2000 to 2006 in four locations of two Brazilian biomes (Pantanal and Cerrado), were tested for rabies antibodies. Twenty-six individuals (12.3%) had neutralizing antibody titers >= 0.10 IU/ml. The four sampled locations had antibody-positive animals, suggesting that Rabies virus circulates in all of these regions. Results underscore the risk posed by rabies for conservation of Brazilian carnivores and the possibility of the animals acting as reservoirs for the Rabies virus.

SEROPREVALENCE OF TOXOPLASMA GONDII ANTIBODIES IN CAPTIVE WILD MAMMALS AND BIRDS IN BRAZIL

In this study, serum samples of 203 animals from different locations, from zoos and breeding facilities from the north and northeast regions of Brazil, were analyzed for the presence of anti-Toxoplasma gondii antibodies by the modified agglutination test (MAT) with a cutoff of 1:25. Of the sampled animals, 184 were adult mammals of both sexes and 19 were birds. Antibodies were found in 61 of 184 mammals, and no association between sex and age of the animals and the presence of T. gondii antibodies was observed (P < 0.05). Anti-T gondii antibodies were not found in birds. Toxoplasma gondii was detected in Brazilian tapir (Tapirus terrestris) for the first time.

Occurrence of antibodies anti-Neospora caninum, anti-Toxoplasma gondii, and anti-Leishmania chagasi in serum of dogs from Para State, Amazon, Brazil

A cross-sectional study was conducted to determine the occurrence of anti-Toxoplasma gondii, anti-Neospora caninum, and anti- Leishmania chagasi antibodies in dogs of the state of Para, Brazil. For this purpose, 129 blood samples were collected from dogs of different ages and gender. Samples of 72 dogs were collected from 39 rural properties from 19 municipalities, and 57 samples were from stray dogs, collected after captivity by the Center of Zoonosis Control from the municipality of Santar,m. The sera were analyzed for anti-T. gondii and anti-N. caninum antibodies by indirect fluorescent antibody tests with cutoff values of 1:16 and 1:50, respectively. For the presence of L. chagasi antibodies, enzyme-linked immunosorbent assay was used and positive results were confirmed by immunochromatographic method using the recombinant antigen K39. Of the total of 129 dogs, 90 (69.8%) were positive for T. gondii, 16 (12.4%) for N. caninum, and 30 (23.3%) for L. chagasi. Antibodies for all three parasites were found simultaneously in seven dogs (5.4%), mostly in urban dogs (six of seven). No association was observed related to gender and location (urban or rural) of dogs and occurrence of N. caninum and T. gondii antibodies although, regarding L. chagasi, higher prevalence was found in females (P < 0.02) and in dogs from urban location (P < 0.001). From the 39 farms, in 30 (76.9%) at least one dog was positive for T. gondii or N. caninum or both. Higher occurrence of Leishmania antibodies was observed in N. caninum-negative dogs (P < 0.05).