It is known that levels of the anti-apoptotic protein survivin are reduced during Murine norovirus MNV-1 and Feline calicivirus (FCV) infection as part of the apoptosis establishment required for virus release and propagation in the host. Recently, our group has reported that overexpression of survivin causes a reduction of FCV protein synthesis and viral progeny production, suggesting that survivin may affect early steps of the replicative cycle. Using immunofluorescence assays, we observed that overexpression of survivin, resulted in the reduction of FCV infection not only in transfected but also in the neighboring nontransfected CrFK cells, thus suggesting autocrine and paracrine protective effects. Cells treated with the supernatants collected from CrFK cells overexpressing survivin showed a reduction in FCV but not MNV-1 protein production and viral yield, suggesting that FCV binding and/or entry were specifically altered. The reduced ability of FCV to bind to the surface of the cells overexpressing survivin, or treated with the supernatants collected from these cells, correlate with the reduction in the cell surface of the FCV receptor, the feline junctional adhesion molecule (fJAM) 1, while no effect was observed in the cells transfected with the pAm-Cyan vector or in cells treated with the corresponding supernatants. Moreover, the overexpression of survivin affects neither Vaccinia virus (VACV) production in CrFK cells nor MNV-1 virus production in RAW 267.4 cells, indicating that the effect is specific for FCV. All of these results taken together indicate that cells that overexpress survivin, or cell treatment with the conditioned medium from these cells, results in the reduction of the fJAM-1 molecule and, therefore, a specific reduction in FCV entry and infection.

The protection of the neonate against pathogens depends largely on the antibodies transferred placentally from the mother; for this reason, maternal vaccination against emerging viruses, such as SARS-CoV-2, is of vital importance. Knowing some of the immunogenic factors that could alter the placental transfer of antibodies could aid in understanding the immune response and neonatal protection after maternal vaccination. In this study, we analyzed the efficiency of the placental transfer of binding and neutralizing antibodies, as well as some factors that could alter the passive immune response, such as the trimester of gestation at the time of immunization, the number of doses received by the mother and the type of vaccine. Binding IgG antibodies were detected by ELISA, and the detection of neutralizing antibodies was carried out using flow cytometry. Our results show efficient transfer rates (>1), which are higher when maternal vaccination occurs during the third trimester of gestation. Antibodies are detectable in mothers and their neonates after 12 months of maternal immunization, suggesting than the vaccination against COVID-19 before and during pregnancy in the Mexican population induces a lasting neutralizing response in mothers and their newborns.

In the present study, we evaluated the influence of maternal and neonatal factors on the efficiency of the placental transfer of neutralizing antibodies against SARS-CoV-2. Vaccination during pregnancy provides fetal and neonatal protection through the passive transplacental transfer of maternal neutralizing antibodies. To date, little information is available regarding the factors that affect the transfer of antibodies against SARS-CoV-2. A retrospective, cross-sectional, observational, and analytical study was carried out. It was found that several biological factors could be altering transplacental passive immunity after vaccination against COVID-19. In our study population, type 2 diabetes mellitus and chronic hypertension tended to decrease efficiency, while data from women with pre-eclampsia showed better indices compared to those from women with healthy pregnancies. Neonates born prematurely showed lower transfer rates when compared to healthy neonates. The premature rupture of membranes significantly decreased antibody transfer. Taken together, the data suggest that vaccination against COVID-19 during pregnancy is effective even under certain unfavorable clinical conditions for the mother, fetus, and neonate. It is important to create and disseminate immunization strategies in vulnerable populations to reduce maternal and perinatal morbidity and mortality associated with infections preventable by vaccination.

Extracellular vesicles (EVs) are lipid bilayer-bound structures capable of transporting molecular markers from their cell of origin and are secreted by multiple cell types, including malignant cells. EVs have emerged as promising tools for developing less invasive diagnostic approaches. In B-cell acute lymphoblastic leukemia (B-ALL), immunophenotypic characterization of extracellular vesicle-enriched populations (EVEPs) in peripheral blood (PB) may provide complementary information for disease detection and monitoring. This exploratory study aimed to characterize EVEPs obtained from PB and bone marrow (BM) of adult patients with B-ALL and to compare them with the clinical immunophenotype (CIP). A total of 12 individuals were initially recruited (eight with B-ALL, one with T-ALL, and three healthy controls). The study focused on the eight B-ALL patients and three controls, while the T-ALL sample was used as a specificity control. EVEPs were isolated by differential centrifugation and analyzed by flow cytometry and confocal microscopy, primarily evaluating CD3 and CD19 expression. EVEPs derived from PB samples of patients with B-ALL showed a higher percentage of marker-positive events by flow cytometry (CD45, CD34, CD19, CD20, and CD10), consistent with the leukemic phenotype identified in the CIP. Additionally, CD3⁺CD19⁺ EVEPs were occasionally detected. These findings suggest that EVEPs partially reflect the leukemic immunophenotype and may serve as a complementary source of biological information. The detection of CD3⁺CD19⁺ events highlights complex cellular interactions within the leukemic niche and warrants further investigation.

Extracellular vesicles (EVs) are lipid bilayer–bound structures capable of transporting molecular markers from their cell of origin and are secreted by multiple cell types, including malignant cells. EVs have emerged as promising tools for developing less invasive diagnostic approaches. In B-cell acute lymphoblastic leukemia (B-ALL), immunophenotypic characterization of extracellular vesicle–enriched populations (EVEPs) in peripheral blood (PB) may provide complementary information for disease detection and monitoring. This exploratory study aimed to characterize EVEPs obtained from peripheral blood (PB) and bone marrow (BM) of adult patients with B-ALL and to compare them with the clinical immunophenotype (CIP). EVEPs were isolated by differential centrifugation and analyzed by flow cytometry and confocal microscopy, primarily evaluating CD3 and CD19 expression. EVEPs derived from PB samples of patients with B-ALL showed increased expression of B-lineage markers (CD45, CD34, CD19, CD20, and CD10), consistent with the leukemic phenotype identified in the CIP. Additionally, CD3⁺CD19⁺ EVEPs were occasionally detected. These findings suggest that EVEPs partially reflect the leukemic immunophenotype and may serve as a complementary source of biological information. The detection of CD3⁺CD19⁺ events highlights complex cellular interactions within the leukemic niche and warrants further investigation.