Lack of association of the KIR and HLA class I ligands with ZIKV infection in south and southeast of Brazil

BACKGROUND Zika virus (ZIKV) is an emerging arbovirus associated with foetal malformations and neurological complications. The infection is usually associated with mild symptoms. The comparison between the allelic frequency of polymorphic genes in symptomatic infected individuals in the population can clarify the pathogenic mechanisms of ZIKV. During ZIKV infection, cytokines are produced and natural killer (NK) cells are recruited, whose activation depends on signaling pathways activated by specific receptors, such as killer cell immunoglobulin-like receptors (KIR). These molecules interact with human leukocyte antigen (HLA) class I ligands and are encoded by polymorphic genes. OBJECTIVES This study aimed to evaluate the frequency of allelic variants of the genes encoding the KIR receptors and their HLA class I ligands in 139 symptomatic ZIKV-patients and 170 controls negative for the virus, and to evaluate the role of these variants for ZIKV susceptibility. METHODS KIR and HLA class I genes were genotyped using the polymerase chain reaction-sequence specific oligonucleotide (PCR-SSO) technique. FINDINGS No significant differences in the frequency distribution of KIRs and KIR-HLA in patients compared to controls were observed. MAIN CONCLUSIONS KIR and its HLA ligands might play a minor role in ZIKV infection in the south and southeast Brazilian individuals.

Molecular diagnosis of symptomatic toxoplasmosis: a 9-year retrospective and prospective study in a referral laboratory in São Paulo, Brazil

ABSTRACT Symptomatic forms of toxoplasmosis are a serious public health problem and occur in around 10-20% of the infected people. Aiming to improve the molecular diagnosis of symptomatic toxoplasmosis in Brazilian patients, this study evaluated the performance of real time PCR testing two primer sets (B1 and REP-529) in detecting Toxoplasma gondii DNA. The methodology was assayed in 807 clinical samples with known clinical diagnosis, ELISA, and conventional PCR results in a 9-year period. All samples were from patients with clinical suspicion of several features of toxoplasmosis. According to the minimum detection limit curve (in CT), REP-529 had greater sensitivity to detect T. gondii DNA than B1. Both primer sets were retrospectively evaluated using 515 DNA from different clinical samples. The 122 patients without toxoplasmosis provided high specificity (REP-529, 99.2% and B1, 100%). From the 393 samples with positive ELISA, 146 had clinical diagnosis of toxoplasmosis and positive conventional PCR. REP-529 and B1 sensitivities were 95.9% and 83.6%, respectively. Comparison of REP-529 and B1 performances was further analyzed prospectively in 292 samples. Thus, from a total of 807 DNA analyzed, 217 (26.89%) had positive PCR with, at least one primer set and symptomatic toxoplasmosis confirmed by clinical diagnosis. REP-529 was positive in 97.23%, whereas B1 amplified only 78.80%. After comparing several samples in a Brazilian referral laboratory, this study concluded that REP-529 primer set had better performance than B1 one. These observations were based after using cases with defined clinical diagnosis, ELISA, and conventional PCR.

Anticardiolipin antibodies and recurrent spontaneous abortion in Brazilianwomen / Anticardiolipin antibodies and recurrent spontaneous abortion in Brazilianwomen

Aims: To determine the frequency of anti-cardiolipin antibodies (aCL) in women with previous history of recurrent spontaneous abortion (RSA).Methods: Medical records from pregnant women seen from April 2005 to December 2008 at the High-Risk Pregnancy Unit at the Hospital de Base from FUNFARME (Fundação Faculdade Regional de Medicina), in São José do Rio Preto, São Paulo, Brazil, were revised. Patients olderthan 18 years who had at least two spontaneous abortions and who were tested for aCL wereincluded in the study. Data on maternal age, number of miscarriages and the results of serological tests for aCL were recorded. The exact Fisher's test was used to compare the results. A p value less than 0.05 was considered significant.Results: During the study period a total of 294 pregnant women were seen, from whom 44 consecutive women fulfilled the inclusion criteria. The overall mean age was 33.8±5.4 years (range: 22 to 44; median: 34). Eighteen (40.9%) patients were reagent for aCL and 26 (59.1%) non-reagent,and the difference between their mean age was not statistically significant (reagent: 34.6±5.8 years; non reagent: 33.2±5.2 years, p=0.4001). Fourteen (77.8%) patients presented IgM aCL and six (33.2%), IgG aCL. Two patients (11%) were reagent for both IgM and IgG aCL. In the most of cases the aCL antibody titers were compatible with low risk for pregnancy morbidity. The number of abortions ranged from two to six. The average number of abortions among those reagent for aCL was 3.5±1.1 and in those non-reagent was 2.9±1.1 (p=0.0813). Conclusions: The frequency of aCL was elevated among patients with a history of RSA,especially those having higher number of fetal losses. Among women with at least two spontaneousabortions, the mean number of abortions was not significantly different between those reagent for aCL and those non reagent.

Objetivos: Avaliar a frequência de anticorpos anticardiolipina (aCL) em mulheres comhistória prévia de aborto espontâneo recorrente (AER).Métodos: No período de abril de 2005 a dezembro de 2008 foram avaliados os dados deprontuários de gestantes atendidas no Ambulatório de Gestação de Alto Risco do Hospital de Baseda Fundação Faculdade Regional de Medicina (FUNFARME), em São José do Rio Preto, SãoPaulo, Brasil. Foram incluídas neste estudo pacientes com idade acima de 18 anos que tiveram pelomenos dois abortos espontâneos e foram avaliadas para aCL. O teste exato de Fisher foi usado paracomparar os resultados. Valor de p menor que 0,05 foi considerado significante.Resultados: Um total de 294 mulheres gestantes foram avaliadas durante o período doestudo, das quais 44 atendiam aos critérios de inclusão. A média de idade foi 33,8±5,4 anos(variação: 22 a 44; mediana: 34). Dezoito pacientes (40,9%) foram reagentes para aCL e 26 (59,1%)não reagentes, e a diferença entre a média de idade não foi estatisticamente significante (reagentes:34,6±5,8 anos; não reagentes: 33,2±5,2 anos, p=0,4001). Quatorze (77,8%) pacientes apresentaramaCL IgM e seis (33,2%) aCL IgG. Duas pacientes (11%) foram reagentes para ambas as classes deaCL, IgM e IgG. Na maioria dos casos os títulos de anticorpos aCL foram compatíveis com baixorisco para morbidade na gravidez. O número de abortos variou de dois a seis. O número médio deabortos entre as reagentes para aCL foi de 3,5±1,1 e entre as não reagentes foi de 2,9±1,1(p=0,0813).Conclusões: A frequência de aCL foi alta entre as pacientes com história de AER,especialmente entre aquelas que tiveram um maior número de perdas fetais. Entre as mulheres compelo menos dois abortos espontâneos, a média do número de abortos não foi significativamentediferente entre aquelas reagentes e não reagentes para aCL.