Human extracellular vesicles and correlation with two clinical forms of toxoplasmosis.

AIM: This study analyzed microvesicles and exosomes, called as extracellular vesicles (EVs) excreted in serum and cerebrospinal fluid (CSF) from patients with cerebral or gestational toxoplasmosis. METHODS: Clinical samples from 83 individuals were divided into four groups. Group I, 20 sera from healthy individuals and pregnant women (seronegative for toxoplasmosis); group II, 21 sera from seropositive patients for toxoplasmosis (cerebral or gestational forms); group III, 26 CSF samples from patients with cerebral toxoplasmosis/HIV co-infection (CT/HIV) (seropositive for toxoplasmosis); and group IV, 16 CSF samples from seronegative patients for toxoplasmosis, but with HIV infection and other opportunistic infections (OI/HIV). Serum and CSF samples were ultracentrifuged to recover EVs. Next, vesicle size and concentration were characterized by Nanoparticle Tracking Analysis (NTA). RESULTS: Concentrations of serum-derived EVs from toxoplasmosis patients (mean: 2.4 x 1010 EVs/mL) were statically higher than of non-infected individuals (mean: 5.9 x 109 EVs/mL). Concentrations of CSF-derived EVs were almost similar in both groups. CT/HIV (mean: 2.9 x 109 EVs/mL) and OI/HIV (mean: 4.8 x 109 EVs/mL). Analyses by NTA confirmed that CSF-derived EVs and serum-derived EVs had size and shape similar to microvesicles and exosomes. The mean size of EVs was similar in serum and CSF. Thus, the concentration, and not size was able distinguish patients with toxoplasmosis than healthy individuals. Presence of exosomes was also confirmed by transmission electron microscopy and evidence of tetraspanins CD63 and CD9 in immunoblotting. Relative expressions of miR-146a-5p, miR-155-5p, miR-21-5p, miR-29c-3p and miR-125b-5p were estimated in exosomal miRNA extracted of EVs. Serum-derived EVs from group II (cerebral and gestational toxoplasmosis) up-expressed miR-125b-5p and miR-146a-5p. CSF-derived EVs from CT/HIV patients) up-expressed miR-155-5p and miR-21-5p and were unable to express miR-29c-3p. CONCLUSION: These data suggest the participation of EVs and exosomal miRNAs in unbalance of immune response as elevation of TNF-α, IL-6; and downregulation of IFN-γ in cerebral and gestational forms of toxoplasmosis.

Central nervous system immune reconstitution inflammatory syndrome in AIDS: experience of a Mexican neurological centre.

BACKGROUND: Highly active antiretroviral therapy (HAART) restores the inflammatory immune response in AIDS patients and it may unmask previous subclinical infections or paradoxically exacerbate symptoms of opportunistic infections. Up to 25% of patients receiving HAART develop immune reconstitution inflammatory syndrome (IRIS). We describe six patients with IRIS central nervous system (CNSIRIS) manifestations emphasizing the relevance of CSF cultures and neuroimaging in early diagnosis and management. METHODS: Patients with CNSIRIS were identified among hospitalized HIV-infected patients that started HAART from January 2002 through December 2007 at a referral neurological center in Mexico. RESULTS: One-hundred and forty-two HIV-infected patients with neurological signs were hospitalized, 64 of which had received HAART, and six (9.3%) developed CNSIRIS. Five patients were male. Two cases of tuberculosis, two of cryptococcosis, one of brain toxoplasmosis, and one possible PML case were found. IRIS onset occurred within 12 weeks of HAART in five patients. Anti-infective therapy was continued. In one case, HAART was temporarily suspended. In long-term follow-up the clinical condition improved in all patients. CONCLUSIONS: CNSIRIS associated to opportunistic infections appeared in 9% of patients receiving HAART. Interestingly, no cases of malignancy or neoplasm IRIS-related were found. Frequent clinical assessment and neuroimaging studies supported diagnosis and treatment. Risk factors were similar to those found in other series.

Neurotoxoplasmosis and AIDS. Cerebrospinal fluid analysis in 96 patients.

The behavior of CSF inflammatory pattern in patients with AIDS and/or toxoplasmosis of the CNS is studied in 176 patients, divided in three groups. In the first group, 96 patients with toxoplasmosis and AIDS are considered; in the second group, 50 patients with toxoplasmosis without AIDS; in the third group, 30 AIDS patients without toxoplasmosis nor any other opportunistic infection. It is possible to conclude that patients with toxoplasmosis associated to AIDS exhibit CSF inflammatory pattern similar to patients with neurotoxoplasmosis without AIDS, except in respect to gamma globulin rates for which a cumulative effect can be detected.

Neurotoxoplasmosis and AIDS: cerebrospinal fluid analysis in 96 patients

Foram estudados 176 pacientes com o objetivo de avaliar o comportamento da reaçäo inflamatória no líquido cefalorraqueano (LCR) de pacientes com toxoplasmose do sistema nervoso central (SNC). Foram considerados três grupos de pacientes: o primeiro com toxoplasmose do SNC associada à síndrome de imunodeficiência adquirida (AIDS), com 96 pacientes; o segundo, com toxoplasmose, sem AIDS, com 50 pacientes; o terceiro, apenas com AIDS, sem qualquer infecçäo oportunista, com 20 pacientes. Verificou-se que o comportamento da reaçäo inflamatória da toxoplasmose do SNC estudada, pelo exame de LCR predomina sobre as características de base da AIDS, excepto no que diz respeito aos teores de globulinas gama; para estas, parece haver efeito comulativo das duas patologias