title: Detection of Toxoplasma gondii soluble antigen, SAG-1(p30), antibody and immune complex in the cerebrospinal fluid of HIV positive or negative individuals.
abstract: Active infection by T. gondii was evaluated by immunoassay for soluble SAG-1 (p30), the major surface antigen from T. gondii, specific antibodies and immune complexes in human cerebrospinal fluid (CSF) samples. A total of 263 samples of CSF were collected from hospitalized patients presenting neurological disorders and analyzed for antibodies to HIV. Patients were divided into two groups: HIV positive (n = 96) or HIV negative (n =167). The results of the assays showed that 45% of all samples were positive for soluble SAG-1. Toxoplasma Ag/Ab immune complexes were detected in 19% of the CSF samples and 62% were positive for T. gondii- specific IgG. A combination of these assays in the presence of clinical findings consistent with active Toxoplasma infection may predict the presence of toxoplasmic encephalitis. Moreover, detection of soluble SAG-1 in the CSF of these individuals appears consistent with active infection.
authors.affiliation: Laboratory of Immunology, Department of Pathology, Universidade Federal de Uberlândia, Uberlândia, MG, 38400-902, Brazil.
authors.forename: F A
authors.initials: FA
authors.lastname: Chaves-Borges
authors.forename: M A
authors.initials: MA
authors.lastname: Souza
authors.forename: D A
authors.initials: DA
authors.lastname: Silva
authors.forename: L H
authors.initials: LH
authors.lastname: Kasper
authors.forename: J R
authors.initials: JR
authors.lastname: Mineo
mesh_terms: D000818:Animals; D000913:Antibodies, Protozoan / Q000134:cerebrospinal fluid*; D000936:Antigen-Antibody Complex / Q000134:cerebrospinal fluid*; D000953:Antigens, Protozoan / Q000134:cerebrospinal fluid*; D000954:Antigens, Surface / Q000134:cerebrospinal fluid; D015658:HIV Infections / Q000134:cerebrospinal fluid / Q000276:immunology*; D006801:Humans; D007074:Immunoglobulin G / Q000134:cerebrospinal fluid*; D007223:Infant; D007231:Infant, Newborn; D051379:Mice; D008807:Mice, Inbred BALB C; D015800:Protozoan Proteins / Q000134:cerebrospinal fluid*; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D014122:Toxoplasma / Q000276:immunology*
chemical_list: D000913:Antibodies, Protozoan; D000936:Antigen-Antibody Complex; D000953:Antigens, Protozoan; D000954:Antigens, Surface; D007074:Immunoglobulin G; D015800:Protozoan Proteins; C047168:SAG1 antigen, Toxoplasma