Patients with B-non-Hodgkin lymphoma (NHL) are at increased risk of morbidity and mortality from SARS-CoV-2. We investigated the relationship between B cell cytopenia and the SARS-CoV-2 vaccine response in B-NHL patients. We measured anti-RBD antibodies and the lymphocyte immunophenotype in 19 controls, 22 lymphoma patients on observation (cohort 1) and 55 lymphoma patients receiving their vaccines post B-cell depleting therapy (cohort 2). Half of the lymphoma patients in both cohorts achieved seropositivity compared to 100% of controls. In cohort 2, only 5% achieved an antibody response in the first year post B-cell depleting treatment, vs 88% treated >2 years prior. Also, 28% of patients with <50 B cells/µl achieved a serologic response vs 86% of patients with B-cell >50 B cells/µl. B-cell cytopenia is profound within the first year of exposure to B-cell depleting treatment, therefore an additional dose of vaccine within that timeframe is unlikely to raise antibody levels.

No abstract

El objetivo de esta investigación fue conocer y analizar el grado de comprensión, aplicación, resultados, efectos y limitantes de la implementación de la tecnología milpa intercalada en árboles frutales (MIAF), por los campesinos de cinco municipios Mixes participantes durante el proceso 1999-2009 en el proyecto. La investigación fue mediante una encuesta por muestreo estratificado, para la aplicación de cuestionarios a una muestra de 52 campesinos. Posterior a la fase de campo, la fase documental integró revisión de literatura, captura y el análisis de la información. Los resultados señalan que los campesinos decidieron innovar en componentes como la poda, injerto, trazos de curvas a nivel, siembra de la milpa dentro del sistema MIAF y la no quema del rastrojo. Y el rechazo o adaptación de ciertos componentes del sistema MIAF fue por la estructura sociocultural y económica del campesino. Esta adopción y adaptación o rechazo de los componentes del sistema MIAF, determinó un incremento al rendimiento del maíz y obtención de ingresos económicos para la familia campesina Mixe, además del desarrollo de capacidades del campesino, evidenciando que estos resultados no determinan que la concepción de esta innovación sea total por los campesinos. Durante este proceso, el campesino ha pasado gradualmente por el proceso de decisión para la adopción del sistema MIAF, conociendo, persuadiendo, decidiendo y por último confirmando, en la etapa f inal, donde efectivamente el campesino decide innovar y/o rechazar, con base en la experiencia obtenida con el sistema MIAF, en un primer acercamiento.

Background: Chronic lymphocytic leukemia (CLL) has a classic immunophenotype, consisting of light chain restriction, CD5+, CD19+, dim CD20, CD23+, CD43+, CD200+, CD10- and CD79b-. This distinguishes it from normal B cells and other lymphoproliferative disorders (LPDs). Antibodies targeting these antigens are included in two 8-color flow cytometry panels developed by the Euroflow consortium for the work up of B cell LPDs. Combining these antibodies into one 10-color panel would be more cost-effective. Furthermore, new CLL therapies can induce deep remissions, creating an increasing demand to measure minimal residual disease (MRD), defined as having over 1 residual leukemic cell per 10,000 leukocytes (10-4). The current international standardized approach for measuring MRD established by the European Research Initiative on CLL (ERIC) uses a panel of antibodies targeting CD3, CD5, CD19, CD20, CD22, CD43, CD79b and CD81. However, these antibody-fluorochrome combinations are different than those used by the Euroflow diagnostic panels. Thus laboratories considering implementing MRD testing would need to purchase antibodies for 3 different panels (2 diagnostic and 1 MRD). We expanded the Euroflow 8-color lymphocyte screening tube (LST) to include CD200 and CD23, such that CLL can be detected in one 10-color tube, at levels as low as 0.01%. The goal of this study was to determine the potential cost savings in implementing this new panel and to determine if it is sensitive enough to detect MRD. Methods: We calculated the number of samples analyzed with our modified 10-color LST tube (mLST1, obtained lyophilized) from April 2018 to March 2019 to rule out an LPD and the number of antibody aliquots saved using this approach compared to the standard 2-tube Euroflow method. We also created a version of the above-mentioned panel (mLST2) using liquid antibodies to increase the generalizability of our results, substituting CD38 with CD43 to see if this improved MRD detection (see panels below). For MRD testing, we used CLL samples from 24 different patients to produce 60 MRD samples at various concentrations of leukemic cells. Samples were prepared by spiking CLL cells into suspensions of normal leukocytes at approximate concentrations of 0.1%, 0.01% and 0.001%. Each sample was aliquoted and stained with the three panels: ERIC, mLST1 and mLST2. Data was acquired using a BD FACSCanto II or a BD FACSAria Fusion and analysed using BD FACSDiva software. CLL cells were identified based on differential expression of key markers and MRD was calculated as the number of CLL cells/total leukocytes. MRD positivity was defined as ≥ 0.01%. Agreement between the panels was assessed using the Bland-Altman plot method. We also calculated the percentage agreement between the panels in identifying MRD positivity. Results: In 1 year, mLST1 was performed on 474 samples, of these 220 had an LPD and 123 (56%) had a classic CLL phenotype, obviating the need for further testing. This resulted in the net savings of 476 antibody aliquots. For MRD assessment, differential expression of CD5 and CD20 were the most significant contributors in distinguishing CLL from normal B cells using the mLST1 and mLST2. We identified one CLL case with an atypical immunophenotype (dim CD5, bright CD20) which proved difficult to gate using a mLST panel. There was agreement in MRD results obtained with the mLST panels and the ERIC panel. For values above the limit of quantification, the 95% limit of agreement was ±0.3369 log for the ERIC vs mLST1 comparison and ±0.3485 log for the ERIC vs mLST2 comparison. Thus, variability in MRD levels between the panels was less than 2-fold the majority of the time, which we considered clinically acceptable as MRD is measured on an exponential scale. The ERIC panel and the mLST1 had 88.3% agreement in distinguishing MRD-positive versus MRD-negative samples. Agreement was 93.3% between the ERIC panel and the mLST2. Conclusions: Using a modified 10-color LST panel for both diagnosis and MRD measurement of CLL is feasible. The advantages are increased familiarity with the antibodies and potential cost savings, making MRD accessible to more cytometry laboratories. Atypical CLL cases without the usual CD5 positivity and dim CD20 are very difficult to gate using an LST panel. In these cases, the ERIC panel is clearly superior as CD22, CD79b, CD81 and CD43 can still provide separation between the malignant and normal lymphocytes. Disclosures Bazinet: BD Biosciences: Other: Provided a significant amount of the antibodies used in this project free of cost.. Wever:Teva Canada Innovation: Employment. Gimmig:BD Biosciences: Employment. Johnson:Lundbeck: Employment, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel fees, gifts, and others, Research Funding; Merck: Consultancy, Honoraria; Roche: Consultancy, Employment, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel fees, gifts, and others, Research Funding; Abbvie: Consultancy, Employment, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; BD Biosciences: Other: Provided a significant proportion of the antibodies used in this project free of cost.; BMS: Consultancy, Honoraria; Seattle Genetics: Honoraria.

Salmonella enterica has been increasingly implicated in foodborne outbreaks involving low-moisture foods (LMF) during the recent decade. This study aimed to investigate the potential for persistence of S. enterica in a range of LMF during storage at three temperatures. LMF products, boil-in-bag eggs (freeze-dried product), chocolate protein drink, cran-raspberry First Strike bars, mocha dessert bar, and peanut butter, were inoculated with a five-strain cocktail of S. enterica and stored at 4, 25, or 40°C for 36 months. Salmonella populations remained above 7 log CFU/g in all products stored at 4°C and above 6 log CFU/g in products stored at 25°C, excluding the cran-raspberry First Strike bars. Storage at 40°C resulted in Salmonella populations above 5.5 log CFU/g in boil-in-bag eggs after 36 months and demonstrated survivability for 12 months or less in the other five products. Additionally, a mocha bar production temperature profile study identified rapid cooling of bars in which the temperatures reached would have no measurable impact on Salmonella populations. The results indicate the ability of Salmonella to survive in a variety of LMF category foods, even under adverse storage conditions and identifies how the food matrix may affect Salmonella survivability. The data indicate the importance of establishing food processing procedures that adequately mitigate the presence of Salmonella throughout food processing systems, while also increasing comprehensive understanding of Salmonella survivability mechanisms. HIGHLIGHTS