Molecular mechanisms involved in HIV latency and implications for HIV treatment and eradication

The aim of this presentation is to review the molecular mechanisms necessary for the establishment of HIV-1 latency, their relationship with different cellular and anatomic reservoirs, as well as the current treatment strategies targeting viral persistence in latent reservoirs, their main limitations and future perspectives.S

Occurrence of the Oribatid Mite Trhypochthoniellus longisetus longisetus (Acari: Trhypochthoniidae) on Tilapia (Oreochromis niloticus).

Mites as parasites infesting fish have been described in a few case reports involving Histiostoma anguillarum, H. papillata, and Schwiebea estradai. We describe the unexpected occurrence of oribatid mites of the genus Trhypochthoniellus on farmed tilapia Oreochromis niloticus. The fish had mites on the skin, fins, and gills, as well as in the mouth. The morphological characteristics of the mites, observed by optical and scanning electron microscopy, were consistent with those described for T. longisetus longisetus. All stages of development were observed, suggesting that the mites were able to actively reproduce on fis

Measles in Vaccinated People: Epidemiology and Challenges in Surveillance and Diagnosis in the Post-Elimination Phase. Spain, 2014-2020

The MMR vaccination program was introduced in Spain in 1981. Consistently high vaccination coverage has led to Spain being declared free of endemic measles transmission since 2014. A few imported and import-related cases were reported during the post-elimination phase (2014 to 2020), with very low incidence: three cases per million of inhabitants a year, 70% in adults. In the post-elimination phase an increasing proportion of measles appeared in two-dose vaccinated individuals (up to 14%), posing a challenge to surveillance and laboratory investigations. Severity and clinical presentation were milder among the vaccinated. The IgM response varied and the viral load decreased, making the virus more difficult to detect. A valid set of samples (serum, urine and throat swab) is strongly recommended for accurate case classification. One third of measles in fully vaccinated people was contracted in healthcare settings, mainly in doctors and nurses, consistent with the important role of high intensity exposure in measles breakthrough cases. Surveillance protocols and laboratory algorithms should be adapted in advanced elimination settings. Reinforcing the immunity of people working in high exposure environments, such as healthcare settings, and implementing additional infection control measures, such as masking and social distancing, are becoming crucial for the global aim of measles eradication.This research was funded by the “Instituto de Salud Carlos III” and is one of the objectives of Research Project number PI19ICIII/0041.S

The Detection of SARS-CoV-2 Antibodies in an Exposed Human Population Is Biased by the Immunoassay Used: Implications in Serosurveillance

The presence of SARS-CoV-2 antibodies was examined over 7 months in a population of essential service workers exposed during the first epidemic wave in Madrid (Spain). Results obtained with different serological assays were compared. Firstly, serum samples obtained in April 2020 were analyzed using eleven SARS-CoV-2 antibody detection methods, including seven ELISAs, two CLIAs and two LFAs. While all of the ELISA tests and the Roche eCLIA method showed good performance, it was poorer for the Abbott CLIA and LFA tests. Sera from 115 workers with serologically positive results in April were collected 2 and 7 months after the first sampling and were analyzed using five of the tests previously assessed. The results showed that while some ELISA tests consistently detected the presence of anti-SARS-CoV-2 antibodies even 7 months after first detection, other methods, such as the Abbott CLIA test, showed an important reduction in sensitivity for these mature antibodies. The sensitivity increased after establishing new cut-off values, calculated taking into account both recent and old infections, suggesting that an adjustment of assay parameters may improve the detection of individuals exposed to the infection.This research was funded by the Madrid City Council (Specific epidemiological and health studies of COVID-19 to know the prevalence of the disease in essential operational sectors).S

Evaluation of the LIAISON XL Zika Capture IgM II for the Diagnosis of Zika Virus Infections

The aim of this study is to evaluate the performance characteristics of the LIAISON XL Zika Capture IgM II. For this purpose we tested 128 samples obtained from recent infections caused by the Zika (ZIKV; 74 samples), dengue (DENV; 10 samples), chikungunya (CHIK V; 11 samples), rubella (RUBV; 10 samples) and measles (MeV; 10 samples) viruses, as well as human parvovirus B19 (HPVB19; 13 samples). The results of the assay under evaluation are compared with those obtained from an indirect immunofluorescence (IIF) assay, and the discrepancies are resolved by considering other laboratory results (PCR and a plaque-reduction neutralization test). The LIAISON showed excellent sensitivity (100%). The specificity (91.25%) was hampered by some false-positive results in recent dengue virus, chikungunya virus, measles virus and human parvovirus B19 infections. The method evaluated is adequate, but the low specificity makes it necessary to consider the clinical and epidemiological contexts of patients, as well as other laboratory results.Funding: This work has been financed by a contract between the Instituto de Salud Carlos III and Diasorin Iberia(MVP280/18).S

Cluster randomized trial in smoking cessation with intensive advice in diabetic patients in primary care : ITADI Study

Background: It is a priority to achieve smoking cessation in diabetic smokers, given that this is a group of patients with elevated cardiovascular risk. Furthermore, tobacco has a multiplying effect on micro and macro vascular complications. Smoking abstinence rates increase as the intensity of the intervention, length of the intervention and number and diversity of contacts with the healthcare professional during the intervention increases. However, there are few published studies about smoking cessation in diabetics in primary care, a level of healthcare that plays an essential role in these patients. Therefore, the aim of the present study is to evaluate the effectiveness of an intensive smoking cessation intervention in diabetic patients in primary care. Methods/Design: Cluster randomized trial, controlled and multicentric. Randomization unit: Primary Care Team. Study population: 546 diabetic smokers older than 14 years of age whose disease is controlled by one of the primary care teams in the study. Outcome Measures: Continuous tobacco abstinence (a person who has not smoked for at least six months and with a CO level of less than 6 ppm measured by a cooximeter) , evolution in the Prochaska and DiClemente's Transtheoretical Model of Change, number of cigarettes/day, length of the visit. Point of assessment: one- year post- inclusion in the study. Intervention: Brief motivational interview for diabetic smokers at the pre-contemplation and contemplation stage, intensive motivational interview with pharmacotherapy for diabetic smokers in the preparation-action stage and reinforcing intevention in the maintenance stage. Statistical Analysis: A descriptive analysis of all variables will be done, as well as a multilevel logistic regression and a Poisson regression. All analyses will be done with an intention to treatment basis and will be fitted for potential confounding factors and variables of clinical importance. Statistical packages: SPSS15, STATA10 y HLM6. Discussion: The present study will try to describe the profile of a diabetic smoker who receives the most benefit from an intensive intervention in primary care. The results will be useful for primary care professionals in their usual clinical practice

Feeding Calcium Salts of Linseed Oil on Productive Performance and Milk Fatty Acid Profile in Grazing Dairy Cows

The objective of this study was to determine the effect of supplying calcium salts of linseed oil (Ca-FA) rich in omega-3 (α-linolenic acid) on the production and chemical composition of milk and its nutraceutical value in dairy cows in early lactation. The trial lasted 12 weeks (2 weeks for adaptation to lipids and 10 weeks of data collection). A total of 36 Holstein dairy cows with 58.0 ± 17.0 days in milk (DIM), 594.1 ± 92.4 kg BW, 2.6 ± 1.5 parity and 38.9 ± 9.3 kg milk day-1 were used in a randomized complete block design. The treatments were: 1) Omega-3 (O3): 5.2 kg DM day-1 of concentrate including 0.7 kg DM of Ca-FA + 13.5 kg DM day-1 of partial mixed ration (PMR) + 12 kg DM day-1 of alfalfa pasture (Medicago sativa) and 2) Control (C): diet similar to O3 but lipid supplementation was replaced by cracked corn grain so that the diets were isoenergetic. No treatment effect was detected (P > 0.05) for any milk production and composition variables, except for urea in milk that was slightly higher in O3 (P = 0.02). The treatment × week interaction was significant (P 0.05) between treatments. Concentrate intake was higher (P 0.05) in rumen environment parameters. Supplementation with Ca-FA reduced (P < 0.05) the hypercholesterolemic fraction of milk (C12:0, C14:0 and C16:0, -13.6%, -7.4% and -9.0%, respectively). The concentration of α-linolenic acid (C18:3n-3) increased (108%, P < 0.01) in O3 group compared with group C. The absence of negative effects of lipids on the fat content of milk and ruminal fermentation suggests that protection by saponification was effective. The supplementation with Ca-FA (0.85 kg·day-1) improved the healthy value of the milk.EEA RafaelaFil: Moreno González, Yaliska. Universidad de Buenos Aires. Facultad de Agronomía; ArgentinaFil: Iorio, Jesica. Universidad de Buenos Aires. Facultad de Agronomía; ArgentinaFil: Olmeda, María Florencia. Universidad Nacional de Lomas de Zamora. Facultad de Ciencias Agrarias; ArgentinaFil: Curletto, Dino. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Rafaela; ArgentinaFil: Scandolo Lucini, Daniel Edgardo. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Rafaela; ArgentinaFil: Maciel, Martin Guillermo. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Rafaela; ArgentinaFil: Cuatrin, Alejandra. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Rafaela; ArgentinaFil: Palladino, Rafael Alejandro. Universidad Nacional de Lomas de Zamora. Facultad de Ciencias Agrarias; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina.Fil: Perez, Carolina Daiana. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto Tecnología de Alimentos; ArgentinaFil: Salado, Eloy Eduardo. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Rafaela; Argentin

Evolution of antibodies against SARS-CoV-2 over seven months: experience of the Nationwide Seroprevalence ENE-COVID Study in Spain [preprint]

Objectives To analyse temporal trends in SARS-CoV-2 anti-nucleocapsid IgG throughout the four rounds of the nationwide seroepidemiologic study ENE-COVID (April-November 2020), and to compare the fourth-round results of two immunoassays detecting antibodies against nucleocapsid and to S protein receptor-binding domain (RBD). Methods A chemiluminescent microparticle immunoassay (CMIA) was offered to all participants in the first three rounds (Abbott; anti-nucleocapsid IgG). In the fourth round we offered this test and a chemiluminescence immunoassay (CLIA) (Beckman; anti-RBD IgG) to i) a randomly selected sub-cohort, ii) participants who were IgG-positive in any of the three first rounds; and iii) participants who were IgG-positive in the fourth round by point-of-care immunochromatography. Results Immunoassays involving 10,153 participants (82.2% of people invited to donate samples) were performed in the fourth round. A total of 2595 participants (35.1% of participants with immunoassay results in the four rounds) were positive for anti-nucleocapsid IgG in at least one round. Anti-nucleocapsid IgG became undetectable in 43.3% of participants with positive first-round results. Pneumonia was more frequent in participants with anti-nucleocapsid IgG in all four rounds (11.2%) than those in which IgG became undetectable (2.4%). In fourth round, anti-nucleocapsid and anti-RBD IgG were detected in 5.5% and 5.4% participants of the randomly selected sub-cohort, and in 26.6% and 25.9% participants with at least one previous positive result, respectively. Agreement between techniques was 90.3% (kappa: 0.72). Conclusions The response of IgG to SARS-CoV-2 is heterogeneous and conditioned by infection severity. A substantial proportion of the SARS-CoV-2 infected population may have negative serologic results in the post-infection months.N

Regular Humoral and Cellular Immune Responses in Individuals with Chronic Myeloid Leukemia Who Received a Full Vaccination Schedule against COVID-19

Individuals with chronic myeloid leukemia (CML) constitute a unique group within individuals with oncohematological disease (OHD). They receive treatment with tyrosine kinase inhibitors (TKIs) that present immunomodulatory properties, and they may eventually be candidates for treatment discontinuation under certain conditions despite the chronic nature of the disease. In addition, these individuals present a lower risk of infection than other immunocompromised patients. For this study, we recruited a cohort of 29 individuals with CML in deep molecular response who were on treatment with TKIs (n = 23) or were on treatment-free remission (TFR) (n = 6), and compared both humoral and cellular immune responses with 20 healthy donors after receiving the complete vaccination schedule against SARS-CoV-2. All participants were followed up for 17 months to record the development of COVID-19 due to breakthrough infections. All CML individuals developed an increased humoral response, with similar seroconversion rates and neutralizing titers to healthy donors, despite the presence of high levels of immature B cells. On the whole, the cellular immune response was also comparable to that of healthy donors, although the antibody dependent cytotoxic activity (ADCC) was significantly reduced. Similar rates of mild breakthrough infections were observed between groups, although the proportion was higher in the CML individuals on TFR, most likely due to the immunomodulatory effect of these drugs. In conclusion, as with the healthy donors, the vaccination did not impede breakthrough infections completely in individuals with CML, although it prevented the development of severe or critical illness in this special population of individuals with OHD.This work was supported by projects PI21/00877 and PI22CIII/00059 funded by the Strategic Action in Health of the Instituto de Salud Carlos III (ISCIII) and co-funded by the European Regional Development Fund (ERDF) “A way to make Europe”. The work of Sara Rodríguez-Mora is financed by NIH grant R01AI143567. The work of Guiomar Casado is financed by the Consejería de Educación, Universidades, Ciencia y Portavocía of the Comunidad de Madrid. The work of Montserrat Torres is financed by CIBERINFEC (CB21/13/00015), co-financed by ERDF. The work of Clara Sánchez-Menéndez is financed by Programa Investigo, FIBio HRC-IRYCIS, co-financed by ERDF.S

Development of Potent Cellular and Humoral Immune Responses in Long-Term Hemodialysis Patients After 1273-mRNA SARS-CoV-2 Vaccination

Long-term hemodialysis (HD) patients are considered vulnerable and at high-risk of developing severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) infection due to their immunocompromised condition. Since COVID-19 associated mortality rates are higher in HD patients, vaccination is critical to protect them. The response towards vaccination against COVID-19 in HD patients is still uncertain and, in particular the cellular immune response is not fully understood. We monitored the humoral and cellular immune responses by analysis of the serological responses and Spike-specific cellular immunity in COVID-19-recovered and naïve HD patients in a longitudinal study shortly after vaccination to determine the protective effects of 1273-mRNA vaccination against SARS-CoV-2 in these high-risk patients. In naïve HD patients, the cellular immune response measured by IL-2 and IFN-ɣ secretion needed a second vaccine dose to significantly increase, with a similar pattern for the humoral response. In contrast, COVID-19 recovered HD patients developed a potent and rapid cellular and humoral immune response after the first vaccine dose. Interestingly, when comparing COVID-19 recovered healthy volunteers (HV), previously vaccinated with BNT162b2 vaccine to HD patients vaccinated with 1273-mRNA, these exhibited a more robust immune response that is maintained longitudinally. Our results indicate that HD patients develop strong cellular and humoral immune responses to 1273-mRNA vaccination and argue in favor of personalized immune monitoring studies in HD patients, especially if COVID-19 pre-exposed, to adapt COVID-19 vaccination protocols for this immunocompromised population.Funding was obtained from Instituto de Salud Carlos III (ISCIII) RICORS program to RICORS2040 (RD21/0005/0001), FEDER funds; Acción Estratégica en Salud Intramural (AESI), Instituto de Salud Carlos III, grant number AESI PI21CIII_00022 to PP and Healthstar-plus -REACT-UE Grant through Segovia Arana Research Institute Puerta de Hierro Majadahonda-IDIPHIM. JO is a member of VACCELERATE (European Corona Vaccine Trial Accelerator Platform) Network, which aims to facilitate and accelerate the design and implementation of COVID-19 phase 2 and 3 vaccine trials. JO is a member of the INsTRuCT under the MSC grant agreement Nº860003 (Innovative Training in Myeloid Regulatory Cell Therapy) Consortium, a network of European scientists from academia and industry focused on developing innovative immunotherapies.S