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The severity of various diseases is related to the concentration of interleukin 6 (IL-6), a proinflammatory cytokine crucial for the proliferation and differentiation of immunocompetent and hematopoietic cells. In ischemic cerebrovascular disease, it is known that, after traumatic injury, increased plasma levels of IL-6 are associated with neuronal inflammation and brain death. Research has shown that elevated plasma IL-6 levels within the first 12 h after an ischemic vascular event are strong predictors of early mortality. Therefore, developing a device that can detect the presence of IL-6 in a murine model of induced ischemic disease could be beneficial for monitoring the disease and selecting the appropriate treatment in the future. This study aimed to detect IL-6 using biosensors developed within optical fibers; the biosensors were assembled using a self-assembled monolayer technique. Subsequently, detection was carried out using samples from rats (Sprague Dawley strain) with an induced ischemic disease. Samples were left to interact with the sample for 2 h to characterize the changes in the sensor’s transmission response. Both the response of the biosensor to IL-6 and the self-assembly steps were characterized by transmission spectroscopy at wavelengths of 1250–1450 nm and micro-MIR spectroscopy. Spectral changes were observed at different stages of the assembly and detection processes. By performing a PCA on the experimental data, it was possible to observe the clustering of the different assembly stages and the final detection. This allowed for discrimination not only at the stage of the biosensor’s construction but also in its detection of IL-6.

Various immunopathological events characterize the systemic acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Moreover, it has been reported that coronavirus disease 2019 (COVID-19) vaccination and infection by SARS-CoV-2 induce humoral immunity mediated by B-cell-derived antibodies and cellular immunity mediated by T cells and memory B cells. Immunoglobulins, cytokines, and chemokines play an important role in shaping immunity in response to infection and vaccination. Furthermore, different vaccines have been developed to prevent COVID-19. Therefore, this research aimed to analyze and compare Fourier-transform infrared (FTIR) spectra of vaccinated people with a positive (V-COVID-19 group) or negative (V-Healthy group) real-time quantitative reverse transcription-polymerase chain reaction (RT-qPCR) test, evaluating the immunoglobulin and cytokine content as an immunological response through FTIR spectroscopy. Most individuals that integrated the V-Healthy group (88.1%) were asymptomatic; on the contrary, only 28% of the V-COVID-19 group was asymptomatic. Likewise, 68% of the V-COVID-19 group had at least one coexisting illness. Regarding the immunological response analyzed through FTIR spectroscopy, the V-COVID-19 group showed a greater immunoglobulins G, A, and M (IgG, IgA, and IgM) content, as well as the analyzed cytokines interferon-gamma (IFN-γ), tumor necrosis factor-alpha (TNF-ɑ), and interleukins 1β, 6, and 10 (IL-1β, IL-6, and IL-10). Therefore, we can state that it was possible to detect biochemical changes through FTIR spectroscopy associated with COVID-19 immune response in vaccinated people.

Abstract Background Kidney diseases are a global health problem. Currently, over 2 million people require dialysis or transplant which are associated with high morbidity and mortality; therefore, new researches focused on regenerative medicine have been developed, including the use of stem cells. Results In this research, we generate differentiated kidney cells (DKCs) from mouse pluripotent stem cells (mPSCs) analyzing their morphological, genetic, phenotypic, and spectroscopic characteristics along differentiation, highlighting that there are no reports of the use of Fourier transform infrared (FTIR) spectroscopy to characterize the directed differentiation of mPSCs to DKCs. The genetic and protein experiments proved the obtention of DKCs that passed through the chronological stages of embryonic kidney development. Regarding vibrational spectroscopy analysis by FTIR, bands related with biomolecules were shown on mPSCs and DKCs spectra, observing distinct differences between cell lineages and maturation stages. The second derivative of DKCs spectra showed changes in the protein bands compared to mPSCs. Finally, the principal components analysis obtained from FTIR spectra allowed to characterize chemical and structurally mPSCs and their differentiation process to DKCs in a rapid and non-invasive way. Conclusion Our results indicated that we obtained DKCs from mPSCs, which passed through the chronological stages of embryonic kidney development. Moreover, FTIR spectroscopy resulted in a non-invasive, rapid and precise technic that together with principal component analysis allows to characterize chemical and structurally both kind of cells and also discriminate and determine different stages along the cell differentiation process.

Some of the greatest challenges in stem cells (SCs) biology and regenerative medicine are differentiation control of SCs and ensuring the purity of differentiated cells. In this work, we differentiated mouse pluripotent stem cells (mPSCs) toward pancreatic cells characterizing this differentiation process by molecular and spectroscopic technics. Both mPSCs and Differentiated Pancreatic Cells (DPCs) were subjected to a genetic, phenotypic, and biochemical analysis by real-time quantitative PCR (RT-qPCR), immunocytochemistry, and Fourier Transform Infrared (FTIR) spectroscopy. Cultured mPCSs expressed pluripotent genes and proteins (Nanog and SOX2). DPCs expressed endodermal genes (SOX17 and Pdx1) at day 11, an inductor gene of embryonic pancreas development (Pdx1) at day 17 and pancreas genes and proteins (Insulin and Glucagon) at day 21 of differentiation. Likewise, FTIR spectra of mPSCs and DPCs at different maturation stages (11, 17, and 21 days) were obtained and showed absorption bands related with different types of biomolecules. These FTIR spectra exhibited significant spectral changes agreeing with the differentiation process, particularly in proteins and nucleic acids bands. In conclusion, the obtained DPCs passed through the chronological stages of embryonic pancreas development and FTIR spectra provide a new biophysical parameter based on molecular markers indicating the differentiation process of mPSCs to specialized cells.

Lactic acid bacteria (LAB) comprise a group of microorganisms responsible for developing the sensory and chemical characteristics of several foods and fermented products, particularly cheese. For this reason, after isolation and identification of LAB, validated protocols and procedures for their long-term preservation without compromising its integrity and technological properties, as well as methodologies aiming to assess their viability and integrity are paramount. This study aimed to isolate and identify autochthonous LAB from artisanal Adobera cheese and determine the effect of LAB cryopreservation with thioglycolate broth and glycerol on their viability, membrane integrity, and kinetics. Sixteen LAB were isolated and genetically identified from artisanal cheese samples; eleven of those strains were selected (genus Lactobacillus, Leuconostoc, Streptococcus, and Lactococcus) and included in the cryo-preservation assay. The initial average concentration of the bacterial suspensions was 6.89 log10 CFU mL−1; increasing to 8.9 log10 CFU mL−1 21 days later and slightly reduced at day 42 post-preservation (losses below one logarithm). About 77% of the cells maintained their membrane potential 180 days after their preservation and showed normal Kinetic parameters, maintaining normal adaptation times (Lag phase) and Log phases (9 h average), before reaching the stationary phase. The proposed protocol constitutes a viable alternative to the long-term preservation of different LAB genera because it keeps their viability and integrity. Using flow cytometry allowed the enumeration of viable LAB and provide evidence of the integrity of their membrane.

Adobera, a genuine, brick-shaped, lightly ripened, unstretched pasta filata-like cheese from Western México, is one of the most important market-share wise but is usually made with raw milk and prepared following artisanal procedures. A pasteurized milk cheese is needed to assess its safety and guarantee standardized quality features. However, no commercial Adobera cheese culture is available, as specific lactic acid bacteria relevant for its production have not been thoroughly identified. This study is aimed at comparing the technological and quality features of Adobera cheeses made with pasteurized milk inoculated with a mixture of autochthonous lactic acid bacteria (Lactobacillus and Leuconostoc strains) to those of traditional raw milk cheeses, hypothesizing that no significant differences would be found between them. Milk pasteurization promoted water retention into the cheese matrix, impacting its texture and color profiles. Raw milk cheeses were harder, more cohesive, and less elastic than pasteurized milk cheeses. Ripening markers were significantly higher in raw milk cheeses at all sampling times, although its evolution over time showed that the starter culture could exhibit similar proteolytic activity than that of native milk microbiota under favorable ripening conditions. The principal component analysis revealed apparent overall differences between raw Adobera cheeses and those made with pasteurized cheese milk.