Why are tapeworm carriers so difficult to find? A methodological proposal for their search and recovery.

Neurocysticercosis, caused by the larval stage of Taenia solium, is a life-threatening condition and the most severe form of the disease. Yet, despite being a required link in the parasite life cycle, tapeworm carriers are rarely reported. This study is aimed to find and evaluate T. solium carriers, describing some characteristics of these patients and the treatment. Taeniasis cases were searched for in various Mexican states from 1983 to 2016. Previous informed consent, tapeworm-carrier patients were administered with niclosamide and a saline purge. Parasite specimens were recovered and identified, both morphologically and by PCR. From 117 treated patients, Taenia sp. specimens were obtained from 46 subjects (47.8%). From these, complete parasites were recovered from 42 (90.5%), and only detached proglottids from 4 patients. Cases were more frequent in Morelos, Chiapas, and Guerrero. More than one adult cestode was recovered from 4 patients (9.5%). To improve treatment efficacy and adherence, the drug was administered in late afternoon, resulting a high recovery yield of complete parasites (90.5%). The success rate of deworming campaigns in areas of Mexico and the world that are endemic for Taenia sp. could be improved by administering the treatment at times that do not interfere with the patients' daily activities, and national health authorities could apply this simple strategy to help eradication efforts in endemic areas. The detection of carriers will only be possible through the coordinated efforts of public and private health services, a better education of the general population to improve self-detection, and adequate, personalized diagnostic procedures for suspect cases.

The many faces of parasite calreticulin.

Calreticulin from parasites and its vertebrate hosts share ~50% identity and many of its functions are equally conserved. However, the existing amino acid differences can affect its biological performance. Calreticulin plays an important role in Ca2+ homeostasis and as a chaperone involved in the correct folding of proteins within the endoplasmic reticulum. Outside the endoplasmic reticulum, calreticulin is involved in several immunological functions such as complement inhibition, enhancement of efferocytosis, and immune upregulation or inhibition. Several parasite calreticulins have been shown to limit immune responses and promote infectivity, while others are strong immunogens and have been used for the development of potential vaccines that limit parasite growth. Furthermore, calreticulin is essential in the dialogue between parasites and hosts, inducing Th1, Th2 or regulatory responses in a species-specific manner. In addition, calreticulin participates as initiator of endoplasmic reticulum stress in tumor cells and promotion of immunogenic cell death and removal by macrophages. Direct anti-tumoral activity has also been reported. The highly immunogenic and pleiotropic nature of parasite calreticulins, either as positive or negative regulators of the immune response, render these proteins as valuable tools to modulate immunopathologies and autoimmune disorders, as well as a potential treatment of neoplasms. Moreover, the disparities in the amino acid composition of parasite calreticulins might provide subtle variations in the mechanisms of action that could provide advantages as therapeutic tools. Here, we review the immunological roles of parasite calreticulins and discuss possible beneficial applications.

Neurocysticercosis in Latin America: Current epidemiological situation based on official statistics from four countries.

BACKGROUND: Neurocysticercosis (NC) is one of the major parasitic diseases affecting the central nervous system and is endemic in much of Asia, sub-Saharan Africa, and Latin America. Its epidemiology is difficult to assess, although official registries are available in Brazil, Colombia, Ecuador, and Mexico. METHODOLOGY/PRINCIPAL FINDINGS: Using official statistics, we assessed trends in NC hospitalization rates during 1998-2019 in Brazil and Ecuador, during 2004-2019 in Mexico, and during 2009-2019 in Colombia. We also assessed the trend in NC mortality in Brazil (1998-2019), the trend in hospitalizations for NC in a Mexican tertiary-level hospital (Instituto Nacional de Neurología y Neurocirugía [INNN]; 1995-2019), and in Mexican primary care ambulatory clinics (1995-2019). Associations between NC hospitalization rates and the human development index (HDI) were also examined. In Brazil, Ecuador, and Mexico, statistically significant decreases in NC hospitalization rates were observed. In Mexico, a significant increase in the age of patients at INNN was observed, suggesting a decreasing incidence of recent infection. Conversely, a significant increase in NC hospitalization rate was observed in Colombia. HDI was not significantly associated with NC hospitalization rates when adjusting for time. CONCLUSIONS: The downward trends in NC cases in Brazil, Ecuador, and Mexico are encouraging, especially in the context of the PAHO/WHO plan of action to eliminate neglected tropical diseases from the region. On the other hand, in Colombia, the increased NC hospitalization rate is concerning and needs further evaluation so that the authorities can take specific measures. These results should encourage health authorities in other endemic countries to establish a system of official registries to identify where the need for a control program is most urgent. However, it is also important to remember that NC persists, although less frequently in some Latin American countries, and efforts to achieve its control must continue.

Identification of α-L-fucosidase (ALFuc) of Blastocystis sp. subtypes ST1, ST2 and ST3

ABSTRACT Blastocystis sp. is a common intestinal microorganism. The α-L-fucosidase (ALFuc) is an enzyme long associated with the colonization of the gut microbiota. However, this enzyme has not been experimentally identified in Blastocystis cultures. The objective of the present study was to identify ALFuc in supernatants of axenic cultures of Blastocystis subtype (ST)1 ATCC-50177 and ATCC-50610 and to compare predicted ALFuc proteins of alfuc genes in sequenced STs1-3 isolates in human Blastocystis carriers. Excretion/secretion (Es/p) and cell lysate proteins were obtained by processing Blastocystis ATCC cultures and submitting them to SDS-PAGE and immunoblotting. In addition, 18 fecal samples from symptomatic Blastocystis human carriers were analyzed by sequencing of amplification products for subtyping. A complete identification of the alfuc gene and phylogenetic analysis were performed. Immunoblotting showed that the amplified band corresponding to ALFuc (~51 kDa) was recognized only in the ES/p. Furthermore, prediction analysis of ALFuc 3D structures revealed that the domain α-L-fucosidase and the GH29 family's catalytic sites were conserved; interestingly, the galactose-binding domain was recognized only in ST1 and ST2. The phylogenetic inferences of ALFuc showed that STs1-3 were clearly identifiable and grouped into specific clusters. Our results show, for the first time through experimental data that ALFuc is a secretion product of Blastocystis sp., which could have a relevant role during intestinal colonization; however, further studies are required to clarify this condition. Furthermore, the alfuc gene is a promising candidate for a phylogenetic marker, as it shows a conserved classification with the SSU-rDNA gene.

Zoonotic Taenia infections with focus on cysticercosis due to Taenia solium in swine and humans.

Zoonotic taeniasis caused by the adult stage of Taenia solium, Taenia saginata or Taenia asiatica are considered neglected tropical diseases by the World Health Organization. The life cycle of these 3 metazoan species is very similar and includes an intermediate host: pigs in the case of T. solium and T. asiatica, and cattle in the case of T. saginata. By eating meat (pork/T. solium, T. asiatica; beef/T. saginata) containing live cysticerci, humans develop taeniasis, which is practically asymptomatic but is the main risk factor for intermediate hosts to become infected. T. saginata causes bovine cysticercosis, while T. solium and T. asiatica cause swine cysticercosis, of veterinary and economic importance. T. solium cysticerci cause neurological disease in humans: neurocysticercosis. Cysticerci develop after ingesting microscopic eggs released from a human tapeworm carrier. Here we describe the life stages of the parasites, diagnosis, pathogenesis, symptomatology of neurocysticercosis, and prevention and control measures. Highlighting the need to validate diagnostic tools, treatments and vaccination in endemic areas, with the challenge of addressing the most vulnerable populations that lack resources. If people understand the transmission route, avoid eating uncooked or insufficiently cooked meat and have adequate hygienic habits, the life cycle of the 3 zoonotic Taenia species may be interrupted. In addition, we describe the growing field of immune response and immunomodulation elicited by the parasites, which may provide essential tools for diagnosis, treatment, control of taeniasis/cysticercosis, as well as for identification of parasite-derived immunomodulators that could aid in the treatment of emerging inflammatory diseases worldwide.

In Vitro Employment of Recombinant Taenia solium Calreticulin as a Novel Strategy Against Breast and Ovarian Cancer Stem-like Cells.

BACKGROUND AND AIMS: Calreticulin is a chaperone and master regulator of intracellular calcium homeostasis. Several additional functions have been discovered. Human and parasite calreticulin have been shown to suppress mammary tumor growth in vivo. Here, we explored the capacity of recombinant Taenia solium calreticulin (rTsCRT) to modulate cancer cell growth in vitro. METHODS: We used different concentrations of rTsCRT to treat cancer cell lines and analyzed viability and colony formation capacity. We also tested the combination of the IC20 or IC50 doses of rTsCRT and of the chemotherapeutic drug 5-fluorouracil on MCF7 and SKOV3 cell lines. As a control, the non-tumorigenic cell line MCF10-A was employed. The effect of the drug combinations was also assessed in cancer stem-like cells. Additionally, scavenger receptor ligands were employed to identify the role of this receptor in the rTsCRT anti-tumoral effect. RESULTS: rTsCRT has a dose-dependent in vitro anti-tumoral effect, being SKOV3 the most sensitive cell line followed by MCF7. When rTsCRT/5-fluorouracil were used, MCF7 and SKOV3 showed a 60% reduction in cell viability; colony formation capacity was also diminished. Treatment of cancer stem-like cells from MCF7 showed a higher reduction in cell viability, while those from SKOV3 were more sensitive to colony disaggregation. Finally, pharmacological inhibition of the scavenger receptor, abrogated the reduction in viability induced by rTsCRT in both the parental and stem-like cells. CONCLUSION: Our data suggest that rTsCRT alone or in combination with 5-fluorouracil inhibits the growth of breast and ovarian cancer cell lines through its interaction with scavenger receptors.

An Unexpected Case of Lagochilascariasis: Interdisciplinary Management and Use of 12S and 18S rDNA Analysis.

A Mexican 24-year-old male patient was referred to our hospital due to increased left retroauricular volume with skin fistulisation, resembling an infection by the uncommon worm Lagochilascaris minor. The patient was submitted to lateral skull base surgery. No adult worms or eggs were observed during light and scanning electron microscopy analysis, as well as by histopathologic examination of the small piece of removed tissue, only L3 stage larvae of Lagochilascaris spp. were identified. Polymerase chain reaction-sequencing assays were performed using primers for the mitochondrial 12S and the nuclear 18S rDNA gene. DNA of some L minor adults, previously identified, were used as control. The molecular analysis identified the worm as L minor. According to previous reports, lagochilascariasis is a complicated infection that requires an interdisciplinary management by different clinical specialists. This is the first time that 12S and 18S rDNA genes are reported as molecular markers for diagnosis of L minor.

The monetary burden of cysticercosis in Mexico.

BACKGROUND: Taenia solium cysticercosis is a public health and agricultural problem in many low and middle-income countries where health education, sanitation, pig management practices and meat inspection infrastructure are insufficient. Cysticercosis affects both human and animal health and has important economic consequences. Very few studies have been conducted to evaluate the monetary burden of cysticercosis. This study aimed at estimating the 2015 costs associated with cysticercosis in humans and pigs in Mexico. METHODS: The monetary burden of human cysticercosis was estimated based on costs incurred by living with and treating epilepsy and severe chronic headaches associated with neurocysticercosis (NCC). The estimated cost of porcine cysticercosis took into consideration losses due to the reduction in the price of cysticercosis-infected animals. Epidemiologic and economic data were obtained from the published literature, government reports, and setting-specific questionnaires. Latin hypercube sampling methods were employed to sample the distributions of uncertain parameters and to estimate 95% credible regions (95% CRs). All results are reported in 2015 U.S.$. FINDINGS: The overall monetary burden associated with NCC morbidity was estimated at U.S.$215,775,056 (95% CR U.S.$109,309,560 -U.S.$361,924,224), with U.S.$436 (95% CR: U.S.$296 -U.S.$604) lost per patient. If loss of future years of income and productivity due to NCC-associated deaths was included, this value increased by U.S.$54.26 million, assuming that these individuals earned Mexico's median wage salary. An additional U.S.$19,507,171 (95% CR U.S.$5,734,782 -U.S.$35,913,487) was estimated to be lost due to porcine cysticercosis. CONCLUSIONS: This study suggests that T. solium cysticercosis results in considerable monetary losses to Mexico.

Calreticulin in phagocytosis and cancer: opposite roles in immune response outcomes.

Calreticulin (CRT) is a pleiotropic and highly conserved molecule that is mainly localized in the endoplasmic reticulum. Recently, CRT has gained special interest for its functions outside the endoplasmic reticulum where it has immunomodulatory properties. CRT translocation to the cell membrane serves as an "eat me" signal and promotes efferocytosis of apoptotic cells and cancer cell removal with completely opposite outcomes. Efferocytosis results in a silenced immune response and homeostasis, while removal of dying cancer cells brought about by anthracycline treatment, ionizing-irradiation or photodynamic therapy results in immunogenic cell death with activation of the innate and adaptive immune responses. In addition, CRT impacts phagocyte activation and cytokine production. The effects of CRT on cytokine production depend on its conformation, species specificity, degree of oligomerization and/or glycosylation, as well as its cellular localization and the molecular partners involved. The controversial roles of CRT in cancer progression and the possible role of the CALR gene mutations in myeloproliferative neoplasms are also addressed. The release of CRT and its influence on the different cells involved during efferocytosis and immunogenic cell death points to additional roles of CRT besides merely acting as an "eat me" signal during apoptosis. Understanding the contribution of CRT in physiological and pathological processes could give us some insight into the potential of CRT as a therapeutic target.

RNA Purity, Real-Time PCR Sensitivity, and Colon Segment Influence mRNA Relative Expression in Murine Dextran Sodium Sulfate Experimental Colitis.

The dextran sodium sulfate (DSS) model of colitis is widely used as a result of its simplicity and reproducibility and because it mimics clinicopathological disease features. Its effectiveness depends on the mouse strain, DSS MW, and brand. Quantitative RT-PCR (qRT-PCR) is highly sensitive for analyzing cytokine mRNA expression. We analyzed an acute model of DSS treatment in Balb/c mice for the onset of colitis using qRT-PCR for the quantification of a mouse cytokine transcript. We compared differences among 1--and 2-step qRT-PCR for transcript quantification, the effect of multiple concentrations of DSS, and the use of 2 reference genes in 3 portions of the colon. A reliable and sensitive 1-step protocol for qRT-PCR was established with a modified double LiCl precipitation for RNA isolation. The variability of 2 reference genes, ß-actin and eukaryotic elongation factor 2, was compared, and expression of IL-6 was analyzed in 3 segments of the colon. The RNA cleaning protocol prevented inhibition of qRT-PCR by DSS, and RNA loss was minimized. No clinical differences among the different DSS concentrations were seen on d 7, but higher concentrations resulted in the appearance of earlier symptoms. Higher efficiency and sensitivity of the 1-step qRT-PCR reaction using eukaryotic elongation factor 2 were obtained and also less variability. Although expression levels of IL-6 were high in the middle and distal colon, the middle section had consistently less variability in values. Thus, this segment is recommended for future studies. These factors influence the statistical significance of data and need to be considered to get accurate and reliable results and to improve comparisons of the published colitis experiments.

Fate of uptaken host proteins in Taenia solium and Taenia crassiceps cysticerci.

During the study of host-parasite relationships in taeniid parasite diseases, including cysticercosis and hydatidosis, reports have described the presence of host proteins in the cyst fluid and tissue of metacestodes. However, the fate or role of host elements inside the parasite remains barely explored. After the publication of genomes of four cestode species, it became clear that these organisms possess a limited biosynthetic capability. The initial goal of the present study was to determine if uptaken host proteins could be a source of essential amino acids for cysticerci. To track the utilization of uptaken proteins, we added metabolically labeled IgG-3H and GFP-3H to the culture medium of Taenia crassiceps cysticerci. Incorporation of labeled amino acid was evaluated by fluorography in cysticerci extracts. Our results showed that the use of uptaken proteins by cysticerci as a source of amino acids appeared negligible. Exploring alternative fates for the host proteins, proteomic analysis of the protein matrix in calcareous corpuscles was carried out. Since T. crassiceps does not contain calcareous corpuscles, proteomic analyses were performed in corpuscles of Taenia solium cysticerci. Our results demonstrated that host proteins represented approximately 70% of protein content in the calcareous corpuscles. The presence of the two major uptaken host proteins, namely albumin and IgG, was also demonstrated by Western blot in the matrix of corpuscles. Our findings strongly suggested that the uptake and disposal of host proteins involve calcareous corpuscles, expanding the physiological role of these mineral concretions to a far more important level than previously proposed.

Pre-hospitalization, hospitalization, and post-hospitalization costs of patients with neurocysticercosis treated at the Instituto Nacional de Neurologia y Neurocirugia (INNN) in Mexico City, Mexico.

The objective of this study was to estimate the direct costs associated with the diagnosis and treatment of neurocysticercosis (NCC) during pre-hospitalization, hospitalization, and post-hospitalization periods for 108 NCC patients treated at the Instituto Nacional de Neurologia y Neurocirugia (INNN) in Mexico City, Mexico. Information on clinical manifestations, diagnostic tests, hospitalizations, surgical procedures, prescription medication, and other treatments was collected via medical chart reviews. Uncertain values for costs and frequency of treatments were imputed using bootstrap techniques. The average per-patient pre-hospitalization and hospitalization costs were US$ 257 (95% CI: 185 - 329) and US$ 2,576 (95% CI: 2,244 - 2,908), respectively. Post-hospitalization costs tended to decrease over time, with estimates for the first five years post-hospitalization of US$ 475 (95% CI: 423 - 527), US$ 228 (95% CI: 167 - 288), US$ 157 (95% CI: 111 - 202), US$ 150 (95% CI: 106 - 204), and US$ 91 (95% CI: 27 - 154), respectively. NCC results in a significant economic burden for patients requiring hospitalization, with this burden continuing years post-hospitalization.

Mapping the residual incidence of taeniasis and cysticercosis in Colombia, 2009-2013, using geographical information systems: Implications for public health and travel medicine.

BACKGROUND: In Colombia, taeniasis and cysticercosis have been significantly reduced over the past decades, however still reported with implications for public health and travel medicine. METHODS: An observational, retrospective study, in which the incidence of taeniasis and cysticercosis (ICD-10 codes B68s/B69s) in Colombia, 2009-2013, was estimated based on data extracted from the Individual Health Records System (Registro Individual de Prestación de Servicios, RIPS) was performed. The Geographic Information System (GIS) generated national maps showing the distribution of taeniasis and cysticercosis by department by year. RESULTS: During the period, 3626 cases were reported (median 796/year), for a cumulative crude national rate of 7.7 cases/100,000pop; 58.2% corresponded to male; 57% were <40 year-old (10.2% < 9.9 year-old). Cases were 57.6% neurocysticercosis, the rest were taeniasis due to T. solium, T. saginata, ocular cysticercosis and cysticerci in other organs. Bolivar, a touristic department, had the highest cumulated incidence rate (16.17 cases/100,000pop), as also evident across the map series developed in this study. CONCLUSION: Despite the limitations of this study, data presented provide recent estimates of national taeniasis and cysticercosis incidence in the country useful in public health and for travel medicine practitioners, as some highly touristic areas presented higher disease incidence. Improved control, particularly of taeniasis, should be an attainable goal, which among other strategies would require improved sanitation and health education to prevent transmission, but also enhanced surveillance.

Cytokine, antibody and proliferative cellular responses elicited by Taenia solium calreticulin upon experimental infection in hamsters.

Taenia solium causes two diseases in humans, cysticercosis and taeniosis. Tapeworm carriers are the main risk factor for neurocysticercosis. Limited information is available about the immune response elicited by the adult parasite, particularly the induction of Th2 responses, frequently associated to helminth infections. Calreticulin is a ubiquitous, multifunctional protein involved in cellular calcium homeostasis, which has been suggested to play a role in the regulation of immune responses. In this work, we assessed the effect of recombinant T. solium calreticulin (rTsCRT) on the cytokine, humoral and cellular responses upon experimental infection in Syrian Golden hamsters (Mesocricetus auratus). Animals were infected with T. solium cysticerci and euthanized at different times after infection. Specific serum antibodies, proliferative responses in mesenteric lymph nodes and spleen cells, as well as cytokines messenger RNA (mRNA) were analyzed. The results showed that one third of the infected animals elicited anti-rTsCRT IgG antibodies. Interestingly, mesenteric lymph node (MLN) cells from either infected or non-infected animals did not proliferate upon in vitro stimulation with rTsCRT. Additionally, stimulation with a tapeworm crude extract resulted in increased expression of IL-4 and IL-5 mRNA. Upon stimulation, rTsCRT increased the expression levels of IL-10 in spleen and MLN cells from uninfected and infected hamsters. The results showed that rTsCRT favors a Th2-biased immune response characterized by the induction of IL-10 in mucosal and systemic lymphoid organs. Here we provide the first data on the cytokine, antibody and cellular responses to rTsCRT upon in vitro stimulation during taeniasis.

Cost of neurocysticercosis patients treated in two referral hospitals in Mexico City, Mexico.

OBJECTIVES: To estimate annual costs related to the diagnosis, treatment and productivity losses among patients with neurocysticercosis (NCC) receiving treatment at two referral hospitals, the Instituto Nacional de Neurologia y Neurocirugia (INNN) and the Hospital de Especialidades of the Instituto Mexicano del Seguro Social (HE-IMSS), in Mexico City from July 2007 to August 2008. METHODS: Information on presenting clinical manifestations, diagnostic tests, hospitalisations, surgical procedures and other treatments received by NCC outpatients was collected from medical charts, and supplemented by an individual questionnaire regarding productivity losses and out-of-pocket expenses related to NCC. RESULTS: The annual average per-patient direct costs were US$ 503 (95% CI: 414-592) and US$ 438 (95% CI: 322-571) for patients without a history of hospitalisation and/or surgery seen at the INNN and the HE-IMSS, respectively. These costs increased to US$ 2506 (95% CI: 1797-3215) and US$ 2170 (95% CI: 1303-3037), respectively, for patients with a history of hospitalisation and/or surgery. The average annual per-patient indirect costs were US$ 246 (95% CI: 165-324) and US$ 114 (95% CI: 51-178), respectively, using minimum salary wages for individuals not officially employed. CONCLUSIONS: The total annual cost for patients who had and had not been hospitalised and/or undergone a surgical procedure for the diagnosis or treatment of NCC corresponded to 212% and 41% of an annual minimum wage salary, respectively. The disease tends to affect rural socioeconomically disadvantaged populations and creates health disparities and significant economic losses in Mexico.

Short report: Genetic variation of Echinococcus canadensis (G7) in Mexico.

We evaluated the genetic variation of Echinococcus G7 strain in larval and adult stages using a fragment of the mitochondrial cox1 gen. Viscera of pigs, bovines, and sheep and fecal samples of dogs were inspected for cystic and canine echinococcosis, respectively; only pigs had hydatid cysts. Bayesian inferences grouped the sequences in an E. canadensis G7 cluster, suggesting that, in Mexico, this strain might be mainly present. Additionally, the population genetic and network analysis showed that E. canadensis in Mexico is very diverse and has probably been introduced several times from different sources. Finally, a scarce genetic differentiation between G6 (camel strain) and G7 (pig strain) populations was identified.

From stillness to motion: 80 years after the first description of Taenia solium oncosphere hatching.

BACKGROUND: Human neurocysticercosis (NCC) is a considered public health problem in many underdeveloped and developing countries. Because of the enormous increase in international tourism and migration, NCC nowadays is also found in some developed countries. Our group was the first to demonstrate that tapeworm carriers in the household are the main risk factor for acquiring cysticercosis in humans and pigs, since the disease results from the ingestion of microscopic tapeworm eggs. FINDINGS: We had the opportunity to film the liberation of the embryo from the oncospheral membrane after the hatching of the egg, which is the activation process required for intestinal wall invasion by the onchosphere. Yoshino (J Formosa Med Ass 32:139-142, 1933) described with great detail in diagrams and photographs this process eighty years ago after he infected himself with three living cysticerci in order to study the life cycle of Taenia solium. Other authors further described this process. Nevertheless it has never been filmed before. The purpose of this paper is to shift from stillness to motion since we can now show for the first time a movie of an activated oncosphere and its release from the oncospheral membrane. CONCLUSION: Oncospheral activation is the requisite for T. solium embryos to invade the intestinal mucosa and develop into cysticerci. This process has been amply described but here it is shown for the first time in motion; thus it may be of interest for readers of the journal and useful for educational purposes towards the control of NCC.

Plasma cytokine levels and cytokine gene polymorphisms in Mexican patients during the influenza pandemic A(H1N1)pdm09.

BACKGROUND: In Mexico, the initial severe cases of the 2009 influenza pandemic virus A (H1N1) [A(H1N1)pdm09] were detected in early March. The immune mechanisms associated with the severe pneumonia caused by infection with this new virus have not been completely elucidated. Polymorphisms in interleukin genes have previously been associated with susceptibility to infectious diseases due to their influence on cytokine production. OBJECTIVES: The present case-control study was performed to compare several immunologic and genetic parameters of patients and controls during the initial phase of the pandemic. STUDY DESIGN: Sixty-five patients who were hospitalized due to infection with the influenza A(H1N1)pdm09 virus and 46 healthy controls were studied. A hemagglutination inhibition assay (HIA) was performed to measure anti-influenza antibody titers in these subjects. Protein levels of the cytokines interleukin (IL)-4, IL-6, IL-8, IL-10, tumor necrosis factor-α (TNFα), interferon gamma (IFNγ), transforming growth factor beta (TGFß)1 and TGFß2 were quantified in plasma. Single nucleotide polymorphisms in IL6, IL10 and TNFα were also assessed. RESULTS: Influenza patients had lower antibody titers and produced significantly higher levels of IL-6, IL-10 and TNFα than healthy controls. The frequencies of the TNFα -308G, IL-10 -592C and IL-10 -1082A alleles and the IL10 -1082(A/A) genotype were associated with susceptibility to severe disease, while the haplotypes TNFα AG and IL-10 GTA and GCA were associated with protection from severe disease [P=0.016, OR (CI)=0.11 (0.01-0.96); P=0.0187, OR (CI)=0.34 (0.13-0.85); P=0.013, OR (CI)=0.39 (0.18-0.83)]. CONCLUSIONS: This study demonstrates that the influenza A(H1N1)pdm09 patients and healthy controls have different profiles of immune parameters and that there is an association between IL-10 and TNFα polymorphisms and the outcome of this disease.

Genotoxicity induced by Taenia solium and its reduction by immunization with calreticulin in a hamster model of taeniosis.

Genotoxicity induced by neurocysticercosis has been demonstrated in vitro and in vivo in humans. The adult stage of Taenia solium lodges in the small intestine and is the main risk factor to acquire neurocysticercosis, nevertheless its carcinogenic potential has not been evaluated. In this study, we determined the genotoxic effect of T. solium infection in the hamster model of taeniosis. In addition, we assessed the effect of oral immunization with recombinant T. solium calreticulin (rTsCRT) plus cholera toxin as adjuvant on micronuclei induction, as this protein has been shown to induce 33-44% protection in the hamster model of taeniosis. Blood samples were collected from the orbital venous plexus of noninfected and infected hamsters at different days postinfection, as well as from orally immunized animals, to evaluate the frequency of micronucleated reticulocytes as a measure of genotoxicity induced by parasite exposure and rTsCRT vaccination. Our results indicate that infection with T. solium caused time-dependent DNA damage in vivo and that rTsCRT immunization reduced the genotoxic damage induced by the presence of the tapeworms.