RESUMO
This report describes a case of congenital toxoplasmosis in a newborn in Southern Italy. A pregnant mother had been admitted at the 20th week of her pregnancy on account of pharyngodynia and laterocervical lymphadenopathy. Although serological testing of the mother's serum documented a seroconversion with positive IgG and IgM anti-Toxoplasma antibodies during II trimester, the woman refused to perform prenatal diagnosis for congenital toxoplasmosis. Fetal ultrasound scan already showed mild asymmetrical triventricular hydrocephaly and cerebral calcifications. After birth, real-time PCR on cerebrospinal fluid and blood samples of the newborn showed a positive result for 529bp-repeat element DNA of T. gondii, In addition brain magnetic resonance imaging and computed tomography showed a characteristic diffuse brain tissue loss associated with hydrocephalus. For the first time molecular characterization of T. gondii isolate was performed directly from the newborn's CSF samples by using nested-PCR-RFLP of sag-2 and pk1 genes. The PCR-RLFP analysis revealed that the isolate belongs to the clonal type II, the predominant lineage causing human toxoplasmosis, as confirmed by DNA sequencing.
Assuntos
Toxoplasma/genética , Toxoplasmose Congênita/parasitologia , Adulto , Anticorpos Antiprotozoários/sangue , Sequência de Bases , Líquido Cefalorraquidiano/parasitologia , DNA de Protozoário/líquido cefalorraquidiano , DNA de Protozoário/química , Feminino , Genótipo , Técnicas de Genotipagem , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Recém-Nascido , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Gravidez , Toxoplasma/classificação , Toxoplasma/imunologia , Toxoplasmose Congênita/líquido cefalorraquidiano , Toxoplasmose Congênita/diagnóstico por imagemRESUMO
Neutralizing antibodies targeting the receptor binding domain (RBD) of the SARS-CoV-2 Spike (S) are among the most promising approaches against coronavirus disease 2019 (COVID-19) 1,2 . We developed a bispecific, IgG1-like molecule (CoV-X2) based on two antibodies derived from COVID-19 convalescent donors, C121 and C135 3 . CoV-X2 simultaneously binds two independent sites on the RBD and, unlike its parental antibodies, prevents detectable S binding to Angiotensin-Converting Enzyme 2 (ACE2), the virus cellular receptor. Furthermore, CoV-X2 neutralizes SARS-CoV-2 and its variants of concern, as well as the escape mutants generated by the parental monoclonals. In a novel animal model of SARS-CoV-2 infection with lung inflammation, CoV-X2 protects mice from disease and suppresses viral escape. Thus, simultaneous targeting of non-overlapping RBD epitopes by IgG-like bispecific antibodies is feasible and effective, combining into a single molecule the advantages of antibody cocktails.