Indicator Of Cellular Response Research Articles

Evaluation of immune status and selected sirtuins in people living with HIV after fully vaccinating for COVID-19

The introduction of protective vaccination against COVID-19 was a turning point in the fight against the pandemic. Expectations also concerned the effectiveness of vaccines in inducing a strong immune response against the SARS-CoV-2 virus and the length of post-vaccination immunity. This topic seems to be especially important in the case of immunocompromised people such as those living with HIV (PLWH). The aim of the study was to examine the concentration of anti-SARS-CoV-2 IgG antibodies against the S1 subunit of the virus’spike protein as a marker of humoral response and the concentration of interferon-gamma (IFN-γ) as an indicator of cellular response in PLWH undergoing combination antiretroviral therapy (cART) and uninfected people (control group) several months after the COVID-19 booster. Concentrations of selected enzymes from the group of sirtuins (SIRT1,-3,-6) that participate in the course of HIV infection were also examined. Concentrations of IgG and IFN-γ were statistically significantly lower in PLWH compared to the control group. Correlations between IgG and IFN-γ concentrations were found both in PLWH and in the control group. Only the concentration of SIRT-6 was significantly lower in PLWH compared to the control group. Vaccination for COVID-19 enabled good long-term humoral and cellular immunity in both HIV positive and uninfected people. The CD4/CD8 ratio and T CD8+ T lymphocytes count played a role in the long-term immune response to booster vaccination. The introduction of optimal cART stabilized the immune status of PLWH and had a positive effect on the humoral and cellular response against infection SARS-CoV- 2.

Differences in the Concentration of Anti-SARS-CoV-2 IgG Antibodies Post-COVID-19 Recovery or Post-Vaccination.

At the end of 2020, population-based vaccination programs with new generation mRNA-based vaccines began almost all over the world. The aim of the study was to evaluate the titer of anti-SARS-CoV-2 IgG antibodies against the S1 subunit of the virus’s spike protein as a marker of the humoral response in 477 patients and the concentration of interferon-gamma as an indicator of cellular response in 28 individuals. In our studies, we used serological enzyme-linked immunosorbent assays. IgG was measured in weeks 2 and 3 after the first dose and 1–5 weeks after the second dose of an mRNA vaccine in seropositive and seronegative individuals as well as in symptomatic and asymptomatic convalescents. High levels of antibodies were observed in 98% of our vaccinated cohort, and the presence of protective T cells was confirmed in the blood samples of all participants. The humoral immune response is diversified and is visible as early as 2–3 weeks after the first dose of the mRNA vaccine. The level of protection increased significantly after the second dose, with the increase being much greater in pre-vaccine healthy subjects and less in convalescents. In the second and third weeks after the second dose, the concentration of IgG antibodies was the highest, and in the following weeks, it decreased gradually. Regular serological measurements on eight subjects show that antibody titers are lower four months after vaccination than before the second dose.

Analyzing temporal dynamics of cell deformation and intracellular movement with video feature aggregation

BackgroundThe research and analysis of cellular physiological properties has been an essential approach to studying some biological and biomedical problems. Temporal dynamics of cells therein are used as a quantifiable indicator of cellular response to extracellular cues and physiological stimuli.MethodsThis work presents a novel image-based framework to profile and model the cell dynamics in live-cell videos. In the framework, the cell dynamics between frames are represented as frame-level features from cell deformation and intracellular movement. On the one hand, shape context is introduced to enhance the robustness of measuring the deformation of cellular contours. On the other hand, we employ Scale-Invariant Feature Transform (SIFT) flow to simultaneously construct the complementary movement field and appearance change field for the cytoplasmic streaming. Then, time series modeling is performed on these frame-level features. Specifically, temporal feature aggregation is applied to capture the video-wide temporal evolution of cell dynamics.ResultsOur results demonstrate that the proposed cell dynamic features can effectively capture the cell dynamics in videos. They also prove that the Movement Field and Appearance Change Field Feature (MFAFF) can more precisely model the cytoplasmic streaming. Besides, temporal aggregation of cell dynamic features brings a substantial absolute increase of classification performance.ConclusionExperimental results demonstrate that the proposed framework outperforms competing mainstreaming approaches on the aforementioned datasets. Thus, our method has potential for cell dynamics analysis in videos.

Measurement of NF-kappaB in normal and reconstructed human skin in vitro.

The survival of grafted donor skin for the treatment of burn injuries depends on several factors including wound bed vascularisation and the intensity of acute inflammation shortly after injury. However, acceptance rates approximate 50% at best and therefore a clinical need exists for improvement. The aim of the study was to develop a method for assessing the inflammatory response of cells in skin tissue based on activation of the NF-kappa B (NF-kappaB) transcription factor complex, thereby providing a basis for analysing the inflammatory component and anti-inflammatory strategies for tissue-engineered treatments. We have extended a standard method of measuring NF-kappaB in monolayer cultures that relies on determining translocation of the p65 subunit from the cytoplasm to the nucleus. Normal human skin and tissue engineered skin was analysed using an immunofluorescence microscopy technique, that revealed base line NF-kappaB activation in the epidermis and dermis were different. It was possible to determine the activation of NF-kappaB in skin tissue, enabling correlation that NF-kappaB measurement is a sensitive indicator of cellular responses in 3-D tissue. The approach will provide a basis for early responses of skin cells in determining the efficacy of anti-inflammatory delivery via tissue-engineered scaffolds for burn injuries.