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Purpose of Review Review work to create and evaluate educational materials that could serve as a primary prevention strategy to help both providers and patients in Panama, Colombia, and the USA reduce disease burden of Toxoplasma infections. Recent Findings Educational programs had not been evaluated for efficacy in Panama, USA, or Colombia. Summary Educational programs for high school students, pregnant women, medical students and professionals, scientists, and lay personnel were created. In most settings, short-term effects were evaluated. In Panama, Colombia, and USA, all materials showed short-term utility in transmitting information to learners. These educational materials can serve as a component of larger public health programs to lower disease burden from congenital toxoplasmosis. Future priorities include conducting robust longitudinal studies of whether education correlates with reduced adverse disease outcomes, modifying educational materials as new information regarding region-specific risk factors is discovered, and ensuring materials are widely accessible.

Purpose of Review Review international efforts to build a global public health initiative focused on toxoplasmosis with spillover benefits to save lives, sight, cognition and motor function benefiting maternal and child health. Recent Findings Multiple countries’ efforts to eliminate toxoplasmosis demonstrate progress and context for this review and new work. Summary Problems with potential solutions proposed include accessibility of accurate, inexpensive diagnostic testing, pre-natal screening and facilitating tools, missed and delayed neonatal diagnosis, restricted access, high costs, delays in obtaining medicines emergently, delayed insurance pre-approvals and high medicare copays taking considerable physician time and effort, harmful shortcuts being taken in methods to prepare medicines in settings where access is restricted, reluctance to perform ventriculoperitoneal shunts promptly when needed without recognition of potential benefit, access to resources for care, especially for marginalized populations, and limited use of recent advances in management of neurologic and retinal disease which can lead to good outcomes.

Purpose of ReviewReview building of programs to eliminateToxoplasmainfections.Recent FindingsMorbidity and mortality from toxoplasmosis led to programs in USA, Panama, and Colombia to facilitate understanding, treatment, prevention, and regional resources, incorporating student work.SummaryStudies foundational for building recent, regional approaches/programs are reviewed. Introduction provides an overview/review of programs in Panamá, the United States, and other countries. High prevalence/risk of exposure led to laws mandating testing in gestation, reporting, and development of broad-based teaching materials aboutToxoplasma.These were tested for efficacy as learning tools for high-school students, pregnant women, medical students, physicians, scientists, public health officials and general public. Digitized, free, smart phone application effectively taught pregnant women about toxoplasmosis prevention. Perinatal infection care programs, identifying true regional risk factors, and point-of-care gestational screening facilitate prevention and care. When implemented fully across all demographics, such programs present opportunities to save lives, sight, and cognition with considerable spillover benefits for individuals and societies.

Sampling the blood compartment by an invasive procedure such as phlebotomy is the most common approach used for diagnostic purposes. However, phlebotomy has several drawbacks including pain, vasovagal reactions, and anxiety. Therefore, alternative approaches should be tested to minimize patient's discomfort. Saliva is a reasonable compartment; when obtained, it generates little or no anxiety. We setup a multiplexed serology assay for detection of Toxoplasma gondii IgG and IgM, rubella IgG, and CMV IgG, in serum, whole blood, and saliva using novel plasmonic gold (pGOLD) chips. pGOLD test results in serum, whole blood, and saliva were compared with commercial kits test results in serum. One hundred twenty serum/saliva sets (Lyon) and 28 serum/whole blood/saliva sets (Nice) from France were tested. In serum and whole blood, sensitivity and specificity of multiplex T. gondii, CMV, and rubella IgG were 100% in pGOLD when compared to commercial test results in serum. In saliva, sensitivity and specificity for T. gondii and rubella IgG were 100%, and for CMV IgG, sensitivity and specificity were 92.9% and 100%, respectively, when compared to commercial test results in serum. We were also able to detect T. gondii IgM in saliva with sensitivity and specificity of 100% and 95.4%, respectively, when compared to serum test results. Serological testing by multiplex pGOLD assay for T. gondii, rubella, and CMV in saliva is reliable and likely to be more acceptable for systematic screening of pregnant women, newborn, and immunocompromised patients.

International audience; Background:Whereas in Europe most of Toxoplasma gondii genotypes belong to the type II lineage, in Latin America, type II is rare and atypical strains predominate. In North America, data on T. gondii genotypes in humans are scarce.Methods:In this study, T. gondii DNA samples from 67 patients with diagnosed toxoplasmosis in the United States were available for genotyping. Discriminant analysis of principal components was used to infer each atypical genotype to a geographic area where patients were probably infected. Associations between genotype, disease severity, immune status, and geographic region were also estimated.Results:Of 67 DNA samples, 41 were successfully genotyped: 18 (43.9%) and 5 (12.2%) were characterized as types II and III, respectively. The remaining 18 genotypes (43.9%) were atypical and were assigned to a geographic area. Ten genotypes originated from Latin America, 7 from North America, and 1 from Asia (China). In North America, unlike in Europe, T. gondii atypical genotypes are common in humans and, unlike in Latin America, type II strains are still present with significant frequency.Conclusions:Clinicians should be aware that atypical genotypes are common in North America and have been associated with severe ocular and systemic disease and unusual presentations of toxoplasmosis in immunocompetent patients.

Majority of Toxoplasma gondii infections are benign and asymptomatic; however, some patients experience toxoplasmic lymphadenitis (TL). Factors associated as to whether infection will be symptomatic or not are unknown.Dye test titers of patients with acute toxoplasmosis (pregnant and not pregnant) with TL (TL+) were compared with those in patients with asymptomatic acute infection (TL-). Additionally, mean levels of 62 serum cytokines were compared between TL+ and TL- pregnant women and between TL+ pregnant and non-pregnant women.During acute infection, mean dye test titer was higher in TL+ than in TL- patients (p=0.021). In addition, out of 62 cytokines, CXCL9andCXCL10 levels were higher (p0.05) and resistin mean levels were lower (p0.05) in pregnant women with TL+ compared to TL-. Among patients with TL+, levels of VCAM1andCCL2 were lower (p0.05) in pregnant women than in non-pregnant women.Here we report differences in dye test titers in patients with acute infection. Cytokine responses vary according to the presence of TL+ and to the pregnancy status. Factors underlying these differences are presently unknown and require further studies to define individual and combined roles of cytokines in TL+.

Toxoplasma gondii DNA detection is essential to antenatally diagnose a congenital infection and reactivation of a past infection in an immunocompromised patient. Initially, PCR methods targeted the 35-fold repetitive B1 gene, and more recently, coding sequence Rep 529 has been preferred, as it was reported to be repeated 200- to 300-fold and yielded far better sensitivity than amplification of the B1 sequence. To date, few data are available in regard to the efficacy of Rep 529 for non-type II genotypes. In this study, we compared the results of B1 quantitative PCR (qPCR) with those of two different Rep 529 qPCRs performed on 111 samples in two different laboratories (Rep 529-1 and Rep 529-2). The performances of the 3 qPCRs were also compared according to the genotypes of the isolates for 13 type II and 21 non-type II samples. The performance of the Rep 529 target was superior to that of the B1 target regardless of the genotype (threshold cycle [C(T)] values for the Rep 529-1 and Rep 529-2 qPCRs were lower than those for the B1 qPCR [P

Disruption of the actin cytoskeleton with cytochalasin D enhanced the mechanically induced increase in intracellular Ca2+ ([Ca2+]i) in osteoblasts in a manner similar to that of PTH. Stabilization of actin with phalloidin prevented the PTH enhanced [Ca2+]i response to shear. Patch-clamp analyses show that the MSCC is directly influenced by alterations in actin integrity. Introduction: PTH significantly enhances the fluid shear-induced increase in [Ca2+]i in osteoblasts, in part, through increased activation of both the mechanosensitive, cation-selective channel (MSCC) and L-type voltage-sensitive Ca2+ channel (L-VSCC). Both stimuli have been shown to produce dynamic changes in the organization of the actin cytoskeleton. In this study, we examined the effects of alterations in actin polymerization on [Ca2+]i and MSCC activity in MC3T3-E1 and UMR-106.01 osteoblasts in response to shear ± PTH pretreatment. Materials and Methods: MC3T3-E1 or UMR-106.01 cells were plated onto type I collagen–coated quartz slides, allowed to proliferate to 60% confluency, and mounted on a modified parallel plate chamber and subjected to 12 dynes/cm2. For patch-clamp studies, cells were plated on collagen-coated glass coverslips, mounted on the patch chamber, and subjected to pipette suction. Modulators of actin cytoskeleton polymerization were added 30 minutes before the experiments, whereas channel inhibitors were added 10 minutes before mechanical stimulation. All drugs were maintained in the flow medium for the duration of the experiment. Results and Conclusions: Depolymerization of actin with 1–5 μM cytochalasin D (cyto D) augmented the peak [Ca2+]i response and increased the number of cells responding to shear, similar to the increased responses induced by pretreatment with 50 nM PTH. Stabilization of actin with phalloidin prevented the PTH enhanced [Ca2+]i response to shear. Inhibition of the MSCC with Gd3+ significantly blocked both the peak Ca2+ response and the number of cells responding to shear in cells pretreated with either PTH or cyto D. Inhibition of the L-VSCC reduced the peak [Ca2+]i response to shear in cells pretreated with PTH, but not with cyto D. Patch-clamp analyses found that addition of PTH or cyto D significantly increased the MSCC open probability in response to mechanical stimulation, whereas phalloidin significantly attenuated the PTH-enhanced MSCC activation. These data indicate that actin reorganization increases MSCC activity in a manner similar to PTH and may be one mechanism through which PTH may reduce the mechanical threshold of osteoblasts.

In North America (NA) and Europe, the majority of toxoplasmosis cases are benign and generally asymptomatic, whereas in South America (SA) toxoplasmosis is associated with much more severe symptoms in adults and congenitally infected children. The reasons for these differences remain unknown; currently, there is little information from patients in either region on how the immune system responds to infection with Toxoplasma gondii. Here, we report the relative abundance of 51 serum cytokines from acute and chronic toxoplasmosis cohorts of pregnant women from the United States, where approximately one-half of clinical isolates are Type II, and Colombia, where clinical isolates are generally "atypical" or Type I-like strains. Surprisingly, the results showed notably lower levels of 23 cytokines in acutely infected patients from the United States, relative to uninfected US controls. In acutely infected Colombian patients, however, only 8 cytokine levels differed detectably with 4 being lower and 4 higher relative to uninfected controls. Strikingly, there were also differences in the cytokine profiles of the chronically infected patients relative to uninfected controls in the US cohort. Hence, Toxoplasma appears to specifically impact levels of circulating cytokines, and our results may partly explain region-specific differences in the clinical spectrum of toxoplasmosis.

We compared the Abbott Toxo immunoglobulin G (IgG) and IgM IMx assays with the Sabin-Feldman dye test and an IgM enzyme-linked immunosorbent assay (ELISA) in 398 serum samples previously tested in our laboratory (retrospective group) and 1,000 consecutive serum samples, tested as they were received in our laboratory in 1995 (prospective group). In the retrospective group, the IgG IMx had a sensitivity of 100%, specificity of 99.0%, positive predictive value of 99.0%, negative predictive value of 100%, and overall agreement of 99.5%. The percentages for the IgM IMx were 97.8, 99.0, 98.9, 98, and 98.4%, respectively. In the prospective group, the IgG IMx had a sensitivity of 97.8%, specificity of 98.7%, positive predictive value of 97.8%, negative predictive value of 98.7%, and overall agreement of 98.4%. The percentages for the IgM IMx were 88.3, 95.9, 74.7, 98.3, and 95%. A serological profile (IgA and IgE antibodies and the differential agglutination [AC/HS] test) was performed in an attempt to resolve discrepancies. Of 21 serum samples that were positive in the IgM IMx and negative in the IgM ELISA, 19 had serological profiles which were most compatible with an infection acquired in the distant past. Of 8 serum samples which were positive in the IgM ELISA and negative in the IgM IMx, 5 had serological profiles which were most compatible with an infection acquired in the distant past. Of the 55 serum samples that were positive in both IgM tests, 21 were from patients who had serological profiles which were most compatible with an infection acquired in the distal past. In conclusion, our data highlight the importance of confirmatory testing for the diagnosis of recently acquired infection with Toxoplasma gondii. When compared with the dye test and IgM ELISA, the Toxo IgG and IgM IMx assays, respectively, revealed high overall agreement in the retrospective and prospective study.

We compared the Vitek immunodiagnostic assay for detection of immunoglobulin M (IgM) toxoplasma antibodies (VIDAS TXM) with an IgM enzyme-linked immunosorbent assay (ELISA) which we developed. A total of 407 serum samples from 391 adults were used for this study. We also examined 17 serial serum samples from four women who had seroconverted during gestation. We observed a sensitivity of 99.5%, a specificity of 93%, a positive predictive value of 93.6%, a negative predictive value of 99.5%, and a global agreement of 96.3%. In each case of seroconversion the VIDAS TXM became positive at the same time as did the IgM ELISA.

We examined the efficiency of detection of immunoglobulin M (IgM) antibodies to a 35-kDa antigen (P35) of Toxoplasma gondii for serodiagnosis of acute infection in pregnant women. A double-sandwich enzyme-linked immunosorbent assay (ELISA) with recombinant P35 antigen (P35-IgM-ELISA) was used for this purpose. On the basis of the clinical history and the combination of results from the toxoplasma serological profile (Sabin-Feldman dye test, conventional IgM and IgA ELISAs, and the differential agglutination test), the patients were classified into three groups: group I, status suggestive of recently acquired infection; group II, status suggestive of infection acquired in the distant past; group III, status suggestive of persisting IgM antibodies. Eighteen (90.0%) of 20 serum samples from group I patients were positive by the P35-IgM-ELISA, whereas none of the 33 serum samples from group II patients were positive. Only 4 (25.0%) of 16 serum samples from group III patients were positive by the P35-IgM-ELISA, whereas all these serum samples were positive by the conventional IgM ELISA. These results indicate that demonstration of IgM antibodies against P35 by the P35-IgM-ELISA is more specific for the acute stage of the infection than demonstration of IgM antibodies by the ELISA that uses a whole-lysate antigen preparation. Studies with sera obtained from four pregnant women who seroconverted (IgG and IgM antibodies) during pregnancy revealed that two of them became negative by the P35-IgM-ELISA between 4 and 6 months after seroconversion, whereas the conventional IgM ELISA titers remained highly positive. The P35-IgM-ELISA appears to be useful for differentiating recently acquired infection from those acquired in the distant past in pregnant women.