Tuft cell acetylcholine is released into the gut lumen to promote anti-helminth immunity.

Upon parasitic helminth infection, activated intestinal tuft cells secrete interleukin-25 (IL-25), which initiates a type 2 immune response during which lamina propria type 2 innate lymphoid cells (ILC2s) produce IL-13. This causes epithelial remodeling, including tuft cell hyperplasia, the function of which is unknown. We identified a cholinergic effector function of tuft cells, which are the only epithelial cells that expressed choline acetyltransferase (ChAT). During parasite infection, mice with epithelial-specific deletion of ChAT had increased worm burden, fitness, and fecal egg counts, even though type 2 immune responses were comparable. Mechanistically, IL-13-amplified tuft cells release acetylcholine (ACh) into the gut lumen. Finally, we demonstrated a direct effect of ACh on worms, which reduced their fecundity via helminth-expressed muscarinic ACh receptors. Thus, tuft cells are sentinels in naive mice, and their amplification upon helminth infection provides an additional type 2 immune response effector function.

Tuft Cells: Detectors, Amplifiers, Effectors and Targets in Parasite Infection.

Tuft cells have recently emerged as the focus of intense interest following the discovery of their chemosensory role in the intestinal tract, and their ability to activate Type 2 immune responses to helminth parasites. Moreover, they populate a wide range of mucosal tissues and are intimately connected to immune and neuronal cells, either directly or through the release of pharmacologically active mediators. They are now recognised to fulfil both homeostatic roles, in metabolism and tissue integrity, as well as acting as the first sensors of parasite infection, immunity to which is lost in their absence. In this review we focus primarily on the importance of tuft cells in the intestinal niche, but also link to their more generalised physiological role and discuss their potential as targets for the treatment of gastrointestinal disorders.

Generation, culture, and stimulation of small intestinal murine organoids in parasitology research.

Parasitic helminth worms frequently infect the gastrointestinal tract and interact with the intestinal epithelium and specialized cell types within it. Intestinal organoids derived from stem cells that line the intestine represent a transformational technology in the study of epithelial-parasite dialogue. Here, we present a protocol for establishing small intestine organoid cultures and administering parasite products of interest to these cultures. We then describe steps for evaluating their impact by microscopy, flow cytometry, immunohistology, and mRNA gene expression. For complete details on the use and execution of this protocol, please refer to Drurey et al. (2022).1.

Protection from T cell-dependent colitis by the helminth-derived immunomodulatory mimic of transforming growth factor-ß, Hp-TGM.

In animal models of inflammatory colitis, pathology can be ameliorated by several intestinal helminth parasites, including the mouse nematode Heligmosomoides polygyrus. To identify parasite products that may exert anti-inflammatory effects in vivo, we tested H. polygyrus excretory-secretory (HES) products, as well as a recombinantly expressed parasite protein, transforming growth factor mimic (TGM), that functionally mimics the mammalian immunomodulatory cytokine TGF-ß. HES and TGM showed a degree of protection in dextran sodium sulphate-induced colitis, with a reduction in inflammatory cytokines, but did not fully block the development of pathology. HES also showed little benefit in a similar acute trinitrobenzene sulphonic acid-induced model. However, in a T cell transfer-mediated model with recombination activation gene (RAG)-deficient mice, HES-reduced disease scores if administered throughout the first 2 or 4 weeks following transfer but was less effective if treatment was delayed until 14 days after T cell transfer. Recombinant TGM similarly dampened colitis in RAG-deficient recipients of effector T cells, and was effective even if introduced only once symptoms had begun to be manifest. These results are a promising indication that TGM may replicate, and even surpass, the modulatory properties of native parasite HES.

ABO Blood Groups and Incidence of COVID-19 in the Mass Gathering Events in Borriana (Spain), March 2020: A Retrospective Cohort Study.

Our objective was to estimate the incidence of COVID-19 and the ABO blood Groups in the mass-gathering events (MGEs) during the Falles Festival in Borriana (Spain) from 6-10 March 2020. We conducted a population-based retrospective cohort study and measured anti-SARS-CoV-2 antibodies and the ABO of participants. We performed laboratory COVID-19 tests and obtained the ABO in 775 subjects (72.8% of the original exposed cohort): O-group (45.2%), A-group (43.1%), B-group (8.5%) and AB-group (3.4%). Adjusted for confounding factors, including COVID-19 exposure during the MGEs, attack rates of COVID-19 for each ABO group were 55.4%, 59.6%, 60.2%, and 63.7%. The adjusted relative risks were for O-group 0.93 (95% Confidence Interval [CI] 0.83-1.04), for A-group 1.06 (95% CI 0.94-1.18), for B-group 1.04 (95%CI 0.88-1.24), and for AB-group 1.11 (95% CI 0.81-1.51) with no significant differences. Conclusions: Our results suggest no effect of ABO on COVID-19 incidence. We observed weak but not significant protection of the O-group and not a significantly greater infection risk for the remaining groups compared with the O-group. More studies are needed to resolve the controversies regarding the association between ABO and COVID-19.

Complications Post-COVID-19 and Risk Factors among Patients after Six Months of a SARS-CoV-2 Infection: A Population-Based Prospective Cohort Study.

In October 2020, we conducted a population-based prospective cohort study to determine post-COVID-19 complications, recovery, return to usual health, and associated risk factors in 536 cases of COVID-19 outbreak in Borriana (Spain) by administering an epidemiological questionnaire via phone interviews. A total of 484 patients participated (90.3%), age mean 37.2 ± 17.1 years, and 301 females (62.2%). Mild illness was the most common COVID-19 manifestation. After six months, 160 patients (33.1%) suffered at least one complication post-COVID-19, and 47 (29.4%) of them sought medical assistance. The most frequent persistent symptoms were hair loss, fatigue, loss of smell or taste, and headache. Risk factors associated with a complication were female sex (adjusted relative risk, [aRR] = 1.93 95% confidence interval [CI] 1.41-2.65), age 35 years and above (aRR = 1.50 95% CI 1.14-1.99), B blood group (aRR = 1.51 95% CI 1.04-2.16), current smoker (RR = 1.61 95% CI 1.02-2.54), and at least a COVID-19 exposure (aRR = 2.13 95% CI 1.11-4.09). Male sex, age younger than 35 years, and low COVID-19 exposures were associated with better recovery and return to usual health. A third of patients presented persistent symptoms compatible with the long-COVID-19 syndrome. In conclusion, an active medical follow-up of post-COVID-19 patients must be implemented.

BMP signaling in the intestinal epithelium drives a critical feedback loop to restrain IL-13-driven tuft cell hyperplasia.

The intestinal tract is a common site for various types of infections including viruses, bacteria, and helminths, each requiring specific modes of immune defense. The intestinal epithelium has a pivotal role in both immune initiation and effector stages, which are coordinated by lymphocyte cytokines such as IFNγ, IL-13, and IL-22. Here, we studied intestinal epithelial immune responses using organoid image analysis based on a convolutional neural network, transcriptomic analysis, and in vivo infection models. We found that IL-13 and IL-22 both induce genes associated with goblet cells, but the resulting goblet cell phenotypes are dichotomous. Moreover, only IL-13-driven goblet cells are associated with classical NOTCH signaling. We further showed that IL-13 induces the bone morphogenetic protein (BMP) pathway, which acts in a negative feedback loop on immune type 2-driven tuft cell hyperplasia. This is associated with inhibiting Sox4 expression to putatively limit the tuft cell progenitor population. Blocking ALK2, a BMP receptor, with the inhibitor dorsomorphin homolog 1 (DMH1) interrupted the feedback loop, resulting in greater tuft cell numbers both in vitro and in vivo after infection with Nippostrongylus brasiliensis. Together, this investigation of cytokine effector responses revealed an unexpected and critical role for the BMP pathway in regulating type 2 immunity, which can be exploited to tailor epithelial immune responses.

The IL-25-dependent tuft cell circuit driven by intestinal helminths requires macrophage migration inhibitory factor (MIF).

Macrophage migration inhibitory factor (MIF) is a key innate immune mediator with chemokine- and cytokine-like properties in the inflammatory pathway. While its actions on macrophages are well-studied, its effects on other cell types are less understood. Here we report that MIF is required for expansion of intestinal tuft cells during infection with the helminth Nippostrongylus brasiliensis. MIF-deficient mice show defective innate responses following infection, lacking intestinal epithelial tuft cell hyperplasia or upregulation of goblet cell RELMß, and fail to expand eosinophil, type 2 innate lymphoid cell (ILC2) and macrophage (M2) populations. Similar effects were observed in MIF-sufficient wild-type mice given the MIF inhibitor 4-IPP. MIF had no direct effect on epithelial cells in organoid cultures, and MIF-deficient intestinal stem cells could generate tuft cells in vitro in the presence of type 2 cytokines. In vivo the lack of MIF could be fully compensated by administration of IL-25, restoring tuft cell differentiation and goblet cell expression of RELM-ß, demonstrating its requirement upstream of the ILC2-tuft cell circuit. Both ILC2s and macrophages expressed the MIF receptor CXCR4, indicating that MIF may act as an essential co-factor on both cell types to activate responses to IL-25 in helminth infection.

Intestinal epithelial tuft cell induction is negated by a murine helminth and its secreted products.

Helminth parasites are adept manipulators of the immune system, using multiple strategies to evade the host type 2 response. In the intestinal niche, the epithelium is crucial for initiating type 2 immunity via tuft cells, which together with goblet cells expand dramatically in response to the type 2 cytokines IL-4 and IL-13. However, it is not known whether helminths modulate these epithelial cell populations. In vitro, using small intestinal organoids, we found that excretory/secretory products (HpES) from Heligmosomoides polygyrus blocked the effects of IL-4/13, inhibiting tuft and goblet cell gene expression and expansion, and inducing spheroid growth characteristic of fetal epithelium and homeostatic repair. Similar outcomes were seen in organoids exposed to parasite larvae. In vivo, H. polygyrus infection inhibited tuft cell responses to heterologous Nippostrongylus brasiliensis infection or succinate, and HpES also reduced succinate-stimulated tuft cell expansion. Our results demonstrate that helminth parasites reshape their intestinal environment in a novel strategy for undermining the host protective response.

ABO Blood Groups and the Incidence of Complications in COVID-19 Patients: A Population-Based Prospective Cohort Study.

After a COVID-19 outbreak in the Falles festival of Borriana (Spain) during March 2020, a cohort of patients were followed until October 2020 to estimate complications post-COVID-19, considering ABO blood groups (ABO). From 536 laboratory-confirmed cases, 483 completed the study (90.1%) carried by the Public Health Center of Castelló and the Emergency and Microbiology and Clinical Analysis of Hospital de la Plana Vila-real. The study included ABO determination and telephone interviews of patients. The participants had a mean age of 37.2 ± 17.1 years, 300 females (62.1%). ABO were O (41.4%), A (45.5%), B (9.1%), and AB (3.9%). We found no difference in the incidence of COVID-19 infections. A total of 159 (32.9%) patients reported one or more post-COVID-19 complications with divergent incidences after adjustment: O (32.3%), A (32.6%), B (54.1%), and AB (27.6%); B groups had more complications post-COVID-19 when compared with O group (adjusted relative risk [aRR] 95% confidence interval [CI] 1.68, 95% CI 1.24-2.27), and symptoms of fatigue (1.79, 95% CI 1.08-2.95), myalgia (2.06, 95% CI 1.10-3.84), headache (2.61, 95% CI 1.58-4.31), and disorder of vision (4.26 95% CI 1.33-13.60). In conclusion, we observed significant differences in post-COVID-19 complications by ABO, with a higher incidence in B group. Additional research is justified to confirm our results.

"Mass gathering events and COVID-19 transmission in Borriana (Spain): A retrospective cohort study".

OBJECTIVE: Mass gathering events (MGEs) are associated with the transmission of COVID-19. Between 6 and 10 March 2020, several MGEs related to the Falles festival took place in Borriana, a municipality in the province of Castellon (Spain). The aim of this study was to estimate the incidence of COVID-19 and its association with these MGEs, and to quantify the potential risk factors of its occurrence. METHODS: During May and June 2020, a population-based retrospective cohort study was carried out by the Public Health Center of Castelló and the Hospital de la Plana in Vila-real. Participants were obtained from a representative sample of 1663 people with potential exposure at six MGEs. A questionnaire survey was carried out to obtain information about attendance at MGEs and COVID-19 disease. In addition, a serologic survey of antibodies against SARS-Cov-2 was implemented. Inverse probability weighted regression was used in the statistical analysis. RESULTS: A total of 1338 subjects participated in the questionnaire survey (80.5%), 997 of whom undertook the serologic survey. Five hundred and seventy cases were observed with an attack rate (AR) of 42.6%; average age was 36 years, 62.3% were female, 536 cases were confirmed by laboratory tests, and 514 cases were found with SARS-CoV-2 total antibodies. Considering MGE exposure, AR was 39.2% (496/1264). A dose-response relationship was found between MGE attendance and the disease, (adjusted relative risk [aRR] = 4.11 95% confidence interval [CI]3.25-5.19). Two MGEs with a dinner and dance in the same building had higher risks. Associated risk factors with the incidence were older age, obesity, and upper and middle class versus lower class; current smoking was protective. CONCLUSIONS: The study suggests the significance of MGEs in the COVID-19 transmission that could explain the subsequent outbreak in Borriana.

Analysis of the results of the SEIMC External Quality Control Programme. Year 2017. / Análisis de resultados del Programa de Control de Calidad Externo SEIMC. AÑO 2017.

This article provides an analysis of the results obtained in 2017 by the participants inscribed in the External Quality Control Programme of the Spanish Society of Infectious Diseases and Clinical Microbiology (SEIMC), which includes controls for bacteriology, serology, mycology, parasitology, mycobacteria, virology, molecular microbiology, and genotypic bacterial resistance. The results obtained in 2017 confirm the excellent skill and good technical standards found in previous editions. However, the programme again showed that erroneous results can be obtained in any laboratory and even in clinically relevant determinations. Once again, the results of this program highlight the need to implement both internal and external controls, as in the SEIMC programme.

Analysis of the results of the SEIMC External Quality Control Programme. Year 2018. / Análisis de resultados del Programa de Control de Calidad Externo SEIMC. Año 2018.

This article provides an analysis of the results obtained in 2018 by the participants inscribed in the External Quality Control Programme of the Spanish Society of Infectious Diseases and Clinical Microbiology (SEIMC), which includes controls for bacteriology, serology, mycology, parasitology, mycobacteria, virology, molecular microbiology, and genotypic bacterial resistance. The results obtained in 2018 confirm the excellent skill and good technical standards found in the vast majority of Spanish clinical microbiology laboratories, as shown in previous editions. However, the programme again shows that erroneous results can be obtained in any laboratory and even in clinically relevant determinations. Once again, the results of this programme highlight the need to implement both internal and external controls, as in the SEIMC programme.

Analysis of the results of HIV-1, HCV and HBV viral loads of the SEIMC External Quality Control Programme. Year 2017. / Análisis de resultados del Programa de Control de Calidad Externo SEIMC de carga viral del VIH-1, VHC y VHB. Año 2017.

BACKGROUND: Human immunodeficiency virus type 1 (HIV-1) and hepatitis B (HBV) and C virus (HCV) viral load determinations are among the most relevant markers for the follow-up of patients infected with these viruses. External quality control tools are crucial to ensure the accuracy of the results obtained by microbiology laboratories. This article summarised the results obtained from the 2017 SEIMC External Quality Control Programme for HIV-1, HCV, and HBV viral loads and HCV genotyping. METHODS AND RESULTS: In the HIV-1 programme, a total of five standards were sent. One standard consisted of seronegative human plasma, while the remaining four contained plasma from three different viremic patients, in the range of 2-5 log10 copies/mL; two of these standards were identical, with the aim of determining repeatability. A significant proportion of the laboratories (35% on average) obtained values outside the accepted range (mean±0.25 log10 copies/mL), depending on the standard and on the method used for quantification. Repeatability was good, with up to 94% of laboratories reporting results within the limits (D<0.5 log10 copies/mL). The HBV and HCV programme consisted of two standards with different viral load contents. Most of the participants, 82% in the case of HCV and 87% in that of HBV, obtained all the results within the accepted range (mean±1.96 SD log10 UI/mL). CONCLUSIONS: Data from this analysis reinforce the utility of proficiency programmes to ensure the quality of the results obtained by a particular laboratory. Due to the marked interlaboratory variability observed, it is advisable to use the same method and laboratory for patient follow-up.

Analysis of the results of HIV-1, HCV and HBV viral loads of the SEIMC External Quality Control Program. Year 2018. / Análisis de resultados del Programa de Control de Calidad Externo SEIMC de carga viral del VIH-1, VHC y VHB. AÑO 2018.

BACKGROUND: Human immunodeficiency virus type 1 (HIV-1) and hepatitis B (HBV) and C virus (HCV) viral load determinations are among the most relevant markers for the follow-up of patients infected with these viruses. External quality control tools are crucial to ensure the accuracy of the results obtained by microbiology laboratories. This article summarised the results obtained from the 2018 SEIMC External Quality Control Programme for HIV-1, HCV, and HBV viral loads and HCV genotyping. METHODS AND RESULTS: In the HIV-1 program, a total of five standards were sent. One standard consisted of seronegative human plasma, while the remaining four contained plasma from three different viremic patients, in the range of 2-5 log10 copies/mL; two of these standards were identical, with the aim of determining repeatability. A significant proportion of the laboratories (28% on average) obtained values outside the accepted range (mean±0.25 log10 copies/mL), depending on the standard and on the method used for quantification. Repeatability was good, with most laboratories reporting results within the limits (D<0.5 log10 copies/mL). The HBV and HCV programme consisted of two standards with different viral load contents. Most of the participants, 87% in the case of HCV and 88% in the HBV, obtained all the results within the accepted range (mean±1.96 SD log10 UI/mL). CONCLUSIONS: Data from this analysis reinforce the utility of proficiency programmes to ensure the quality of the results obtained by a particular laboratory. Due to the marked interlaboratory variability, it is advisable to use the same method and the same laboratory for patient follow-up.

Analysis of the results of the SEIMC External Quality Control Program. Year 2016. / Análisis de resultados del Programa de Control de Calidad Externo SEIMC. Año 2016.

The External Quality Control Programme of the Spanish Society of Infectious Diseases and Clinical Microbiology (SEIMC) includes controls for bacteriology, serology, mycology, parasitology, mycobacteria, virology, molecular microbiology, and genotypic bacterial resistance. As in previous years, the results obtained in 2016 confirm the excellent skill and good technical standards in the vast majority of clinical microbiology laboratories in Spain. However, erroneous results can be obtained in any laboratory and in clinically relevant determinations. Once again, the results of this programme highlight the need to implement both internal and external controls. Supplement information: This article is part of a supplement entitled «SEIMC External Quality Control Programme. Year 2016¼, which is sponsored by Roche, Vircell Microbiologists, Abbott Molecular and Francisco Soria Melguizo, S.A. © 2019 Elsevier España, S.L.U. and Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica. All rights reserved.

Analysis of the results of the SEIMC External Quality Control Programme for HIV-1, HCV, and HBV viral loads. Year 2016. / Análisis de resultados del Programa de Control de Calidad Externo SEIMC de carga viral del VIH-1, del VHC y del VHB. Año 2016.

BACKGROUND: Human immunodeficiency virus type 1 (HIV-1) and hepatitis B (HBV) and C virus (HCV) viral load determinations are among the most important markers for the follow-up of patients infected with these viruses. Microbiology laboratories have a variety of tools to ensure the accuracy of the results obtained, including external quality control programmes such as that of the Spanish Society of Infectious Diseases and Clinical Microbiology (SEIMC). This article summarises the results of the 2016 SEIMC External Quality Control Programme for HIV-1, HCV, and HBV viral loads. METHODS AND RESULTS: In the HIV-1 programme, a total of 5 standards were sent. One standard consisted of seronegative human plasma, while the remaining 4 contained plasma from 3 different viremic patients, in the range of 2-5 log10 copies/mL. A significant proportion of the laboratories (40% on average) obtained values out of the accepted range (mean ± 0.25 log10 copies/mL), depending on the standard and on the method used for quantification. The HBV and HCV programme consisted of 2 standards with different viral load contents. Most of the participants, 86.5% in the case of HCV and 85.6% in the case of HBV, obtained results that were all within the accepted range (mean ± 1.96 SD log10 UI/mL). CONCLUSIONS: Data from this analysis reinforce the utility of proficiency programmes to ensure the quality of the results obtained by a particular laboratory. Due to the marked interlaboratory variability, it is advisable to use the same method and the same laboratory for patient follow-up. Supplement information: This article is part of a supplement entitled «SEIMC External Quality Control Programme. Year 2016¼, which is sponsored by Roche, Vircell Microbiologists, Abbott Molecular and Francisco Soria Melguizo, S.A. © 2019 Elsevier España, S.L.U. and Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica. All rights reserved.

Exploring the biodiversity of two groups of Oenococcus oeni isolated from grape musts and wines: Are they equally diverse?

One hundred and four Oenococcus oeni isolates were characterised by the carbohydrate fermentation (CH) profile and DNA fingerprinting. Forty-four isolates came from grape must, and 60 from wines sampled at the end of alcoholic fermentation or during malolactic fermentation. The grape must isolates fermented more CH than the wine isolates. In genotypical terms, no clear boundary between grape must and wine isolates was found. Diversities were deduced by considering the isolates of grape must and of wine separately and jointly. By considering only CH fermentation abilities, the group of grape must isolates gave higher diversity index (DICH) values than those isolated from wine; i.e., these isolates were metabolically more diverse. The contrary occurred when the DNA fingerprints were used to calculate DIRAPD-VNTR: wine isolates were genotypically more diverse than grape must ones. With a polyphasic approach, which considered metabolic and genotypic data, the diversity index of both isolate groups (from grape must and wine) was the same, 0.993, which was slightly lower than that calculated from all the isolates (0.997).

[Analysis of the results of the SEIMC External Quality Control Program. Year 2014]. / Análisis de resultados del Programa de Control de Calidad Externo SEIMC. Año 2014.

The External Quality Control Program of the Spanish Society of Infectious Diseases and Clinical Microbiology (SEIMC) include controls for bacteriology, serology, mycology, parasitology, mycobacteria, virology and molecular microbiology. This article presents the most relevant conclusions and lessons from the 2014 controls. As a whole, the results obtained in 2014 confirm the excellent skill and good technical standards found in previous editions. However, erroneous results can be obtained in any laboratory and in clinically relevant determinations. Once again, the results of the SEIMC program highlighted the need to implement both internal and external controls in order to assure the maximal quality of the microbiological tests.

[Analysis of the results of the HIV-1, HCV and HBV viral load of SEIMC External Quality Control Program. Year 2014]. / Análisis de resultados del Programa de Control de Calidad Externo de carga viral del VIH-1, del VHC y del VHB. Año 2014.

Human immunodeficiency virus type 1 (HIV-1), hepatitis B virus (HBV) and hepatitis C virus (HCV) viral load determinations are among the most relevant markers for the follow up of patients infected with these viruses. External quality control tools are crucial to ensure the accuracy of results obtained by microbiology laboratories. This article summarizes the results obtained from the 2014 SEIMC (Spanish Society of Infectious Diseases and Clinical Microbiology) External Quality Control Programme for HIV-1, HCV, and HBV viral loads. In the HIV-1 program, a total of 5 standards were sent. One standard consisted in seronegative human plasma, while the remaining 4 contained plasma from 3 different viremic patients, in the range of 2-5 log10 copies/mL; 2 of these standards were identical aiming to determine repeatability. A significant proportion of the laboratories (30.8% on average) obtained values out of the accepted range (mean ± 0.25 log10 copies/mL), depending on the standard and on the method used for quantification. Repeatability was excellent, with up to 95.8% of laboratories reporting results within the limits (Δ < 0.5 log10 copies/mL). The HBV and HCV program consisted of 2 standards with different viral load contents. Most of the participants, 83.7% in the case of HCV and 87.9% in the HBV, obtained all the results within the accepted range (mean ± 1.96 standard deviations log10 IU/mL). Data from this analysis reinforce the utility of proficiency programmes to ensure the quality of the results obtained by a particular laboratory, as well as the importance of the post-analytical phase on the overall quality. Due to the remarkable interlaboratory variability, it is advisable to use the same method and the same laboratory for patient follow up.