High concordance of ELISA and neutralization assays allows for the detection of antibodies to individual AAV serotypes.

Prescreening of participants in clinical trials that use adeno-associated virus (AAV) vectors is required to identify naive participants, as preexisting neutralizing antibodies can limit the efficacy of AAV gene therapies. The presence of antibodies to individual AAV serotypes is typically detected by neutralization assay. To streamline the screening process, we compared an ELISA-based screening method with a neutralization assay for the detection of antibodies against AAV1, AAV8, and AAV9 in a collection of 50 rhesus macaque sera and 20 human sera.

Eco-Epidemiological Profile and Molecular Characterization of Simian Foamy Virus in a Recently-Captured Invasive Population of (Golden-Headed Lion Tamarin) in Rio de Janeiro, Brazil.

Simian foamy viruses (SFV) infect a wide range of Old World and Neotropical primates (NP). Unlike Old World primates, little is known about the diversity and prevalence of SFV in NP, mainly from a free-living population. Phylogenetic analyses have shown that SFV coevolved with their hosts.

Simian Foamy Viruses in Central and South America: A New World of Discovery.

Foamy viruses (FVs) are the only exogenous retrovirus to date known to infect neotropical primates (NPs). In the last decade, an increasing number of strains have been completely or partially sequenced, and molecular evolution analyses have identified an ancient co-speciation with their hosts. In this review, the improvement of diagnostic techniques that allowed the determination of a more accurate prevalence of simian FVs (SFVs) in captive and free-living NPs is discussed.

Clinical and Molecular Features of Feline Foamy Virus and Feline Leukemia Virus Co-Infection in Naturally-Infected Cats.

Feline foamy virus (FFV) and feline leukemia virus (FeLV) belong to the family. While disease has not been reported for FFV infection, FeLV infection can cause anemia and immunosuppression (progressive infection). Co-infection with FFV/FeLV allows evaluation of the pathogenic potential and epidemiology of FFV infection in cats with FeLV pathology.

First Complete Genome Sequence of a Simian Foamy Virus Infecting the Neotropical Primate Brachyteles arachnoides.

The complete genome sequence of a simian foamy virus infecting the neotropical primate Brachyteles arachnoides (SFVbar) was obtained using next-generation sequencing and genome walking. The full-length SFVbar genome is composed of 11,994 bp and shows a genomic organization similar to that of other neotropical SFVs.

Zoonotic infection of Brazilian primate workers with New World simian foamy virus.

Simian foamy viruses (SFVs) are retroviruses present in nearly all nonhuman primates (NHPs), including Old World primates (OWP) and New World primates (NWP). While all confirmed human infections with SFV are from zoonotic transmissions originating from OWP, little is known about the zoonotic transmission potential of NWP SFV. We conducted a longitudinal, prospective study of 56 workers occupationally exposed to NWP in Brazil.

A non-invasive specimen collection method and a novel simian foamy virus (SFV) DNA quantification assay in New World primates reveal aspects of tissue tropism and improved SFV detection.

Simian foamy viruses (SFVs) co-evolved with a wide range of Old World and New World primates (OWPs and NWPs, respectively) and occasionally transmit to humans. Previous studies of OWPs showed that the predominant site of SFV replication is the oral mucosa. However, very little is known about SFV viral loads (VLs) in the oral mucosa or blood of NWPs.

An expanded search for simian foamy viruses (SFV) in Brazilian New World primates identifies novel SFV lineages and host age-related infections.

Background: While simian foamy viruses have co-evolved with their primate hosts for millennia, most scientific studies have focused on understanding infection in Old World primates with little knowledge available on the epidemiology and natural history of SFV infection in New World primates (NWPs). To better understand the geographic and species distribution and evolutionary history of SFV in NWPs we extend our previous studies in Brazil by screening 15 genera consisting of 29 NWP species (140 monkeys total), including five genera (Brachyteles, Cacajao, Callimico, Mico, and Pithecia) not previously analyzed. Monkey blood specimens were tested using a combination of both serology and PCR to more accurately estimate prevalence and investigate transmission patterns.

Characterization and comparative analysis of a simian foamy virus complete genome isolated from Brazilian capuchin monkeys.

Foamy viruses infect a wide range of placental mammals, including primates. However, despite of great diversity of New World primates, only three strains of neotropical simian foamy viruses (SFV) have been described. Only after 40 years since serological characterization, the complete sequence of an SFVcap strain infecting a family of six capuchin monkeys (Sapajus xanthosternos) was obtained.

Early selection of resistance-associated mutations in HIV-1 RT C-terminal domains across different subtypes: role of the genetic barrier to resistance.

Objectives: Interpretation of drug resistance mutation (DRM) has been based solely on HIV-1 subtype B. Reverse transcriptase (RT) C-terminal domains have been disregarded in resistance interpretation, as their clinical relevance is still controversial. We determined the emergence of DRM in RT C-terminal domains of different HIV-1 subtypes, the genetic barrier for the acquisition of these DRM and their temporal appearance with 'classical' RT inhibitor (RTI) mutations.

Identification and characterization of highly divergent simian foamy viruses in a wide range of new world primates from Brazil.

Foamy viruses naturally infect a wide range of mammals, including Old World (OWP) and New World primates (NWP), which are collectively called simian foamy viruses (SFV). While NWP species in Central and South America are highly diverse, only SFV from captive marmoset, spider monkey, and squirrel monkey have been genetically characterized and the molecular epidemiology of SFV infection in NWPs remains unknown. We tested a large collection of genomic DNA (n = 332) comprising 14 genera of NWP species for the presence of SFV polymerase (pol) sequences using generic PCR primers.

Heterosexual transmission of human immunodeficiency virus type 1 subtype C in southern Brazil.

Background: Human immunodeficiency virus type 1 (HIV-1) subtype B predominates in Brazil, but in the southern region subtype C is the most frequent, followed by subtypes B, F1 and recombinant forms. In southern Brazil, these subtypes co-circulate in subjects with homogeneous demographic and clinical features, enabling a better understanding of the role of HIV-1 subtypes on the characteristics of infection.

Objectives: To evaluate the prevalence of different HIV-1 subtypes in subjects with recent diagnosis for HIV infection in the extreme south of Brazil, and to study their association with demographic, behavioral, clinical and laboratorial characteristics.

Primary HIV-1 drug resistance in the C-terminal domains of viral reverse transcriptase among drug-naïve patients from Southern Brazil.

Background: Major and accessory drug resistance mutations have been recently characterized in the C-terminal RT subdomains of HIV-1, connection and RNase H. However, their presence in treatment-naïve patients infected with HIV-1 non-B subtypes remains largely unknown.

Objectives: To characterize the patterns of primary resistance at the C-terminal RT subdomains of HIV-1 infecting subjects in the southern region of Brazil, where HIV-1 subtypes B and C co-circulate.