T cells and B cells are central components of the adaptive immune system, orchestrating immune responses through a complex network of interactions. This review explores the dynamic interplay between T and B cells, focusing on their development, activation, and functional coordination in immune defense. T cells provide essential help to B cells through cytokine signaling and direct cell–cell interactions, facilitating antibody production and affinity maturation in germinal centers. Conversely, B cells contribute to antigen presentation and cytokine modulation, influencing T cell differentiation and function. The regulation of these interactions is critical for maintaining immune homeostasis, preventing autoimmunity, and enhancing vaccine efficacy. Dysregulation of T-B cell crosstalk is implicated in various immune disorders, including autoimmune diseases and immunodeficiencies. Recent advances in immunotherapy have targeted these pathways to modulate immune responses in conditions such as cancer, infections, and inflammatory diseases. This review synthesizes current knowledge on T and B cell physiology, highlighting emerging research on their cooperative mechanisms.

Background: Following the Coronavirus Disease 2019 (COVID-19) pandemic, many patients have reported ongoing smell and taste issues. This study aims to investigate the prevalence of olfactory and gustatory dysfunction among patients with a history of COVID-19 and its association with autonomic dysfunction and disability. Patient and Methods: This case–control study included a COVID-19 group (n = 82) and a control group (n = 82). Olfactory dysfunction, including parosmia and taste problems, was explored using self-reports and the Quick Smell Identification Test (QSIT). The association between post-COVID-19 disability severity and taste and smell alterations was also analyzed. Moreover, autonomic function was evaluated using the Composite Autonomic Symptom Scale-31 (COMPASS-31) to assess the association between autonomic and olfactory dysfunction. Results: Significantly higher rates of ongoing smell (26.8%) and taste (14.6%) dysfunction were reported for the post-COVID-19 group compared to the control group. Post-COVID-19 patients reported 36.6 times more smell issues and 8.22 times more taste issues than controls. Parosmia scores were significantly worse in the post-COVID-19 group, while QSIT scores showed no significant difference between the groups. However, those with worse QSIT scores exhibited significantly more ongoing smell issues. No significant association was observed between disability and altered smell or taste. Higher secretomotor dysfunction scores were significantly associated with abnormal QSIT scores and worse parosmia scores; the other domains of the COMPASS-31 scale showed no significant associations. Conclusions: The findings indicated a potential link between autonomic and olfactory dysfunction. Further studies are needed to elucidate the mechanisms underlying persistent olfactory and autonomic dysfunction in post-COVID-19 patients.

Maternal separation (MS) animal stress models are commonly used to evaluate the factors affecting cognitive development. These models simulate mother–offspring separation during the lactation period because it is the most critical neurodevelopmental period for exploring the impact of early-life adversities on the risk of various neurological and cognitive disorders that can occur during adulthood. Cognitive dysfunction may result from multiple contradictory mechanisms that have not yet been reviewed. Therefore, in this narrative review, we aim to offer a critical and objective review of studies published in databases, such as PubMed, Google Scholar, and Web of Science, over the last 5 years that have used this stress model to propose a pathophysiological mechanism of MS-induced cognitive dysfunction. Our review reveals that MS induces cognitive dysfunction via the hypothalamic–pituitary–adrenal axis, which may alter neurogenesis and/or apoptosis. Furthermore, MS leads to neuroinflammation, oxidative stress, mitochondrial dysfunction, and accumulation of neuronal aggregates. In conclusion, the MS stress model offers a cost-effective method to evaluate potential therapeutic agents for a variety of neurodegenerative and neuropsychological disorders. Integrating multidisciplinary research into assessments is a comprehensive strategy for the early prevention of these disorders, which is one of the main objectives of the Saudi Arabia 2030 vision for efficient child integration in society.