Diagnosis of toxoplasmosis in a pregnant woman, fetus and infant — current study and new possibilities

W artykule opisano problem toksoplazmozy, skutki oraz obecną diagnostykę. Przedstawiono metody serologiczne pozwalające wykryć pierwotne zarażenie T. gondii u kobiet ciężarnych oraz szereg technik pośrednich i bezpośrednich wykorzystywanych w celu potwierdzenia bądź wykluczenia toksoplazmozy wrodzonej u noworodka. Ponadto wskazano potencjalne możliwości w diagnostyce toksoplazmozy, jakie niosą za sobą nowe techniki (np. 2D Western-blotting), czy stosowanie antygenów rekombinantowych w testach serologicznych.In this article, the problem of toxoplasmosis, ravages and current diagnostics were described. Serological assays detecting primary infection of T. gondii in pregnant women and lots of indirect and direct techniques, which are used in order to confirm or exclude congenital toxoplasmosis in newborn, were represented. Moreover, potential possibilities in diagnosis of toxoplasmosis, such as new techniques (e.g. 2D Western-blotting) or using recombinant antigens were shown

Awidność przeciwciał IgG jako ważny test diagnostyczny w rozpoznawaniu aktywnej toksoplazmozy — stan obecny i nowe możliwości

W artykule opisano problem diagnostyki toksoplazmozy ze szczególnym uwzględnieniemmetody awidności przeciwciał klasy IgG. Test oznaczania awidności przeciwciał IgGswoistych dla T. gondii jest użytecznym wskaźnikiem serologicznym toksoplazmozy, któryw wielu przypadkach na podstawie pojedynczego badania surowicy pacjenta pozwalapotwierdzić lub wykluczyć aktywną postać choroby. W pierwotnej, aktywnej toksoplazmozieprzeciwciała klasy G wskazują niską awidność, natomiast IgG o wysokiej awidnościsą wykrywane w przewlekłym zarażeniu T. gondii. W pracy ponadto przedstawionoistotne zagadnienia obejmujące aktualnie prowadzone badania naukowe, które dotyczązastosowania w teście oznaczania awidności przeciwciał IgG antygenów rekombinantowychpasożyta

Prawidłowe rozpoznanie toksoplazmozy u kobiet ciężarnych - ważność badań diagnostycznych oraz nowe możliwości

Artykuł opisuje problem toksoplazmozy, kliniczne objawy choroby, leczenie, aktualną diagnostykę oraz nowe możliwości testów diagnostycznych. Ponadto, przedstawiono istotne zagadnienia obejmujące aktualnie prowadzone badania naukowe, które dotyczą zastosowania nowych narzędzi diagnostycznych (rekombinantowych antygenów T. gondii) w serodiagnostyce toksoplazmozy. Forum Medycyny Rodzinnej 2010, tom 4, nr 4, 255-26

Toxoplasma gondii Recombinant antigen AMA1: Diagnostic Utility of Protein Fragments for the Detection of IgG and IgM Antibodies

Toxoplasma gondii is an important zoonotic protozoan that infects a wide variety of vertebrates as intermediate hosts. For this reason, the diagnosis of this disease is very important and requires continuous improvement. One possibility is to use recombinant antigens in serological tests. Apical membrane antigen 1 (AMA1), a protein located in specific secretory organelles (micronemes) of T. gondii, is very interesting in regard to its potential diagnostic utility. In the present study, we attempted to identify a fragment of the AMA1 protein with a high sensitivity and specificity for the serological diagnosis of human toxoplasmosis. The full-length AMA1 and two different fragments (AMA1N and AMA1C) were produced using an Escherichia coli expression system. After purification by metal affinity chromatography, recombinant proteins were tested for their utility as antigens in enzyme-linked immunosorbent assays (ELISAs) for the detection of IgG and IgM anti-T. gondii antibodies in human and mouse immune sera. Our data demonstrate that the full-length AMA1 recombinant antigen (corresponding to amino acid residues 67–569 of the native protein) has a better diagnostic potential than its N- or C-terminal fragments. This recombinant protein strongly interacts with specific anti-T. gondii IgG (99.4%) and IgM (80.0%) antibodies, and may be used for developing new tools for diagnostics of toxoplasmosis

IgG Avidity Test as a Tool for Discrimination between Recent and Distant Toxoplasma gondii Infection—Current Status of Studies

Toxoplasma gondii, an obligate intracellular protozoan parasite, is the causative agent of one of the most prevalent zoonoses worldwide. T. gondii infection is extremely important from a medical point of view, especially for pregnant women, newborns with congenital infections, and immunocompromised individuals. Thus, an accurate and proper diagnosis of this infection is essential. Among the available diagnostic tests, serology is commonly used. However, traditional serological techniques have certain limitations in evaluating the duration of T. gondii infection, which is problematic, especially for pregnant women. Avidity of T. gondii-specific IgG antibodies seems to be a significant tool for discrimination between recent and distant infections. This article describes the problem of diagnosis of T. gondii infection, with regard to IgG avidity tests. The IgG avidity test is a useful serological indicator of toxoplasmosis, which in many cases can confirm or exclude the active form of the disease. IgG antibodies produced in the recent primary T. gondii infection are of low avidity while IgG antibodies with high avidity are detected in the chronic phase of infection. Furthermore, this paper presents important topics of current research that concern the usage of parasite recombinant antigens that may improve the performance of IgG avidity tests

Toxoplasma gondii Tetravalent Chimeric Proteins as Novel Antigens for Detection of Specific Immunoglobulin G in Sera of Small Ruminants

The detection of Toxoplasma gondii infection in small ruminants has important significance for public health and veterinary medicine. This study, for the first time, describes the reactivity of four tetravalent chimeric proteins (AMA1N-SAG2-GRA1-ROP1, AMA1C-SAG2-GRA1-ROP1, AMA1-SAG2-GRA1-ROP1, and SAG2-GRA1-ROP1-GRA2) containing immunodominant regions from the AMA1 (apical membrane antigen 1), SAG2 (surface antigen 2), GRA1 (dense granule antigen 1), GRA2 (dense granule antigen 2), and ROP1 (rhoptry antigen 1) with specific IgG antibodies from the sera of small ruminants with the use of an indirect enzyme-linked immunosorbent assay (ELISA). The reactivity of individual chimeric antigens was analyzed in relation to the results obtained in IgG ELISA based on a Toxoplasma lysate antigen (TLA). All chimeric proteins were characterized by high specificity (between 96.39% to 100%), whereas the sensitivity of the IgG ELISAs was variable (between 78.49% and 96.77%). The highest sensitivity was observed in the IgG ELISA test based on the AMA1-SAG2-GRA1-ROP1. These data demonstrate that this chimeric protein can be a promising serodiagnostic tool for T. gondii infection in small ruminants

First report of seroprevalence of Toxoplasma gondii infection in sheep in Pomerania, northern Poland

Introduction and objective Toxoplasmosis is parasitic disease which has economic relevance for both veterinary and human medicine. In sheep, toxoplasmosis is a major cause of abortion and can thus cause reproductive problems. The current study aimed to determine the occurrence of anti-T oxoplasma gondii IgG antibodies in sheep from 13 districts of northern Poland and thereby obtain actual data about T. gondii seroprevalence in this population of animals. Material and Methods Blood samples from 1,646 animals from 99 herds were collected, and an in-house enzyme-linked immunosorbent assay (ELISA) based on native Toxoplasma lysate antigen (TLA) was used for serological testing. The diagnostic sensitivity of diagnostic test used in this study was 98.6%, and specificity 94.9% for the group of 113 sheep sera (74 seropositive and 39 seronegative) previously characterized by using an commercial agglutination test. Results Antibodies against [i]T. gondii[/i] were found in 921 (55.9%) of all tested animals. The percentage of infected sheep was the highest (67.6%) for older animals (>6 years), whereas for younger ones it was significantly lower (50.1% – 57.2% for 1–5-year-old animals, respectively). Furthermore, a higher percentage of seropositive animals was noted among males (63%) than females (55.5%). The results also showed that the size of the herd is not a factor which may affect the seroprevalence of T. gondii infection in the examined population of sheep. Conclusions The results of this study indicate that T. gondii infection in sheep from region of northern Poland is relatively high, and consumption of ovine meat and milk can be regarded as a significant source of infection for humans