Hospital Mortality and Morbidity in Diabetic Patients with COVID-19: A Retrospective Analysis from the UAE.

BACKGROUND: Although we are four years into the pandemic, there is still conflicting evidence regarding the clinical outcomes of diabetic patients hospitalized with COVID-19. The primary objective of this study was to evaluate the in-hospital mortality and morbidity of diabetic versus nondiabetic patients hospitalized with COVID-19 in the Northern UAE Emirates. METHODS: A retrospective analysis was performed on clinical data from patients with or without diabetes mellitus (DM) who were admitted to the isolation hospital with COVID-19 during the first and second waves of the disease (March 2020 to April 2021). The assessed endpoints were all-cause in-hospital mortality, length of hospitalization, intensive care unit (ICU) admission, and mechanical ventilation. RESULTS: A total of 427 patients were included in the analysis, of whom 335 (78.5%) had DM. Compared to nondiabetics, diabetic COVID-19 patients had a significantly longer in-hospital stay (odds ratio (OR) = 2.35; 95% confidence interval (CI) = 1.19-4.62; p = 0.014), and a significantly higher frequency of ICU admission (OR = 4.50; 95% CI = 1.66-7.34; p = 0.002). The need for mechanical ventilation was not significantly different between the two groups (OR: distorted estimates; p = 0.996). Importantly, the overall in-hospital mortality was significantly higher among diabetic patients compared to their nondiabetic counterparts (OR = 2.26; 95% CI = 1.08-4.73; p = 0.03). CONCLUSION: DM was associated with a more arduous course of COVID-19, including a higher mortality rate, a longer overall hospital stay, and a higher frequency of ICU admission. Our results highlight the importance of DM control in COVID-19 patients to minimize the risk of detrimental clinical outcomes.

Hand hygiene knowledge, attitude, and practice before, during and post COVID-19: a cross-sectional study among university students in the United Arab Emirates.

Aims: Hand hygiene (HH) is an essential practice to evade the transmission of germs and minimize community-acquired infections. This study assesses the knowledge, attitude and practice (KAP) of HH and other health and safety measures before, during, and after the COVID-19 pandemic. in university students in the United Arab Emirates (UAE). Methods: A cross-sectional questionnaire study was conducted between December 2022 and March 2023, targeting university students from all disciplines and study levels. A 44-item questionnaire was used which included student demographics, knowledge, attitude, and practice of HH, as well as the anticipated risk of COVID-19 morbidity and mortality. Participants consented before commencing the questionnaire, and the collected data were analysed using the student's t-test and ANOVA test, as required. Results: A total of 378 responses were received nationwide, with a valid response rate of 98%. The HH knowledge revealed an average score of 62%, which was significantly higher in students with moderate family income. Additionally, the average attitude score was 74.7%, as measured on the Likert scale, and the score lacked any correlation with the other variables. HH practice showed an average score of 86.8%, which was correlated with the students' gender and field of study. Conclusions: This study showed a moderate level of knowledge, a good attitude, and good practice around HH and other safety measures among the UAE's university students. Socioeconomic status, gender, and field of study influenced the study outcomes. This study highlights the need for effective awareness campaigns to reinforce students' health and safety, especially for male and non-health science students, in order to protect against communicable diseases.

Specificity of CD8+ T-Cell Responses Following Vaccination with Conserved Regions of HIV-1 in Nairobi, Kenya.

Sub-Saharan Africa carries the biggest burden of the human immunodeficiency virus type 1 (HIV-1)/AIDS epidemic and is in an urgent need of an effective vaccine. CD8+ T cells are an important component of the host immune response to HIV-1 and may need to be harnessed if a vaccine is to be effective. CD8+ T cells recognize human leukocyte antigen (HLA)-associated viral epitopes and the HLA alleles vary significantly among different ethnic groups. It follows that definition of HIV-1-derived peptides recognized by CD8+ T cells in the geographically relevant regions will critically guide vaccine development. Here, we study fine details of CD8+ T-cell responses elicited in HIV-1/2-uninfected individuals in Nairobi, Kenya, who received a candidate vaccine delivering conserved regions of HIV-1 proteins called HIVconsv. Using 10-day cell lines established by in vitro peptide restimulation of cryopreserved PBMC and stably HLA-transfected 721.221/C1R cell lines, we confirm experimentally many already defined epitopes, for a number of epitopes we define the restricting HLA molecule(s) and describe four novel HLA-epitope pairs. We also identify specific dominance patterns, a promiscuous T-cell epitope and a rescue of suboptimal T-cell epitope induction in vivo by its functional variant, which all together inform vaccine design.

In vitro Generation of Cytotoxic T Cells With Potential for Adoptive Tumor Immunotherapy of Multiple Myeloma.

Multiple myeloma is a life-threatening hematological malignancy, which is rarely curable by conventional therapies. Immunotherapy, using tumor antigen-specific, cytotoxic T-lymphocytes, may represent an alternative or additional treatment for multiple myeloma. In this study, we used hybrid cell lines, generated by fusion of an EBV B-lymphoblastoid cell line (B-LCL) and myeloma cells, to stimulate in vitro peripheral blood lymphocytes (PBLs) from patients with multiple myeloma. We investigated induction of antigen-specific, cytotoxic T-lymphocytes to the well-defined tumor associated antigens (TAAs) hTERT, MUC1, MAGE-C1 and CS1, which have been shown to be expressed in a high proportion of cases of multiple myeloma. HLA-A2-peptide pentamer staining, interferon-γ and perforin ELISpot assays, as well as cytotoxicity assays were used. Following several rounds of in vitro stimulation, the hybrid cell lines induced antigen-specific, cytotoxic T-lymphocytes to four candidate TAAs in PBLs from HLA-A2+ multiple myeloma patients, using known HLA-A2 restricted peptide epitopes of the TAAs. In contrast, the HLA-A2+ myeloma cell line U266 failed to induce antigen-specific, cytotoxic T-lymphocytes in vitro. Our data indicate that B-LCL/myeloma hybrid cell lines induce antigen-specific, cytotoxic T-lymphocytes in PBLs isolated from multiple myeloma patients in vitro and may represent a novel strategy for use in adoptive immunotherapy of multiple myeloma.

Effect of lamotrigine on in vivo and in vitro cytokine secretion in murine model of inflammation.

Alteration in cytokine levels, particularly, IL-6, TNF-α, IL-1ß and IL-2, has been implicated in the pathogenesis of epilepsy and bipolar disorder. Lamotrigine (LTG), an antiepileptic drug with mood stabilizing properties, has documented immunomodulatory effects. However, its effect on cytokine secretion in vivo has not been examined. Besides, studies have reported inconsistent results of the in vitro effects of LTG on cytokine secretion. Hence, we used murine models of inflammation to characterize the in vivo and the in vitro effects of LTG on the secretion of the aforementioned cytokines, using ELISA. LTG significantly inhibited basal and mitogen-induced IL-6, TNF-α and IL-1ß secretion in vivo and in LPS-treated RAW264.7 cells in vitro. In PMs, LTG inhibited basal and LPS-induced IL-6 and TNF-α secretion. Our findings extend the current understanding of the anti-inflammatory properties of LTG and may be relevant to its role in modulating the immune system in epilepsy and bipolar disorder.

Evaluation of immunomodulatory effects of lamotrigine in BALB/c mice.

Modulation of the immune system has recently been shown to be involved in the pharmacological effects of old antiepileptic drugs and in the pathogenesis of epilepsy. Therefore, the most recent guidelines for immunotoxicological evaluation of drugs were consulted to investigate the immunomodulatory effects of lamotrigine, a newer antiepileptic drug, in BALB/c mice. These included the in vivo effects of lamotrigine on delayed-type hypersensitivity (DTH) response to sheep red blood cell (SRBC) antigens, hemagglutination titer assays and hematological changes. In vitro effects of lamotrigine on ConA-induced splenocyte proliferation and cytokine secretion were assessed. The results showed that lamotrigine treatment significantly increased the DTH response to SRBC in the mouse model of this study. This was accompanied by a significant increase in relative monocyte and neutrophil counts and in spleen cellularity. Lamotrigine significantly inhibited ConA-induced splenocyte proliferation in vitro and it significantly inhibited IL-2 and TNF-α secretion in ConA-stimulated splenocytes. In conclusion, the results demonstrated significant immunomodulatory effects of lamotrigine in BALB/c mice. These data could expand the understanding of lamotrigine-induced adverse reactions and its role in modulating the immune system in epilepsy.

The in vitro generation of multi-tumor antigen-specific cytotoxic T cell clones: Candidates for leukemia adoptive immunotherapy following allogeneic stem cell transplantation.

Adoptive T-cell immunotherapy is a promising approach to manage and maintain relapse-free survival of leukemia patients, especially following allogeneic stem cell transplantation. Post-transplant adoptive immunotherapy using cytotoxic T lymphocytes (CTLs) of the donor origin provide graft-versus-tumor effects, with or without graft-versus-host disease. Myeloid leukemias express immunogenic leukemia associated antigens (LAAs); such as WT-1, PRAME, MAGE, h-TERT and others, most of them are able to induce specific T cell responses whenever associated with the proper co-stimulation. We investigated the ability of a LAA-expressing hybridoma cell line to induce CTL clones in PBMCs of HLA-matched healthy donors in vitro. The CTL clones were induced by repetitive co-culture with LAAs-expressing, HLA-A*0201(+) hybrid cell line, generated by fusion of leukemia blasts to human immortalized APC (EBV-sensitized B-lymphoblastoid cell line; HMy2). The induced cytotoxic T cell clones were phenotypically and functionally characterized by pentamer analysis, IFN-γ release ELISPOT and cellular cytotoxicity assays. All T cell lines showed robust peptide recognition and functional activity when sensitized with HLA-A*0201-restricted WT-1235-243, hTERT615-624 or PRAME100-108 peptides-pulsed T2 cells, in addition to partially HLA-matched leukemia blasts. This study demonstrates the feasibility of developing multi-tumor antigen-specific T cell lines in allogeneic PBMCs in vitro, using LAA-expressing tumor/HMy2 hybrid cell line model, for potential use in leukemia adoptive immunotherapy in partially matched donor-recipient setting.

Novel mutations of PIK3CA gene in head and neck squamous cell carcinoma.

BACKGROUND: HNSCC is the sixth most common human cancer globally. In Saudi Arabia, HNSCC accounts for seven percent of all newly diagnosed cancer cases. The PIK3CA is one of the most commonly mutated oncogene in human malignancies, including HNSCC. OBJECTIVE: The objective of this study is to identify mutations in exon 9 and exon 20 of the PIK3CA gene among Saudi HNSCC patients, determine the frequency of these mutations and correlate with clinical and pathological findings. METHODS: Histopathologically confirmed paraffin embedded HNSCC tumor tissues from 48 patients were obtained. Capillary sequencing method was used to sequence exons 9 and 20 of the PIK3CA gene. Concurrently, the expression analysis of the PIK3CA and PTEN genes were performed using real-time PCR. RESULTS: Sixty percent of the samples studied were of pharyngeal cancer. A total of seven mutations were identified in exons 9 and 20 of the PIK3CA gene in 14 HNSCC tumor tissue specimens. The seven mutations encompassed one hot spot mutation E542K, a common mutation T1025T and the five novel mutation comprising three missense and two silent mutations. Interestingly, eight out of the 14 samples with a mutation were of patients with pharyngeal cancer. CONCLUSION: PIK3CA gene plays a crucial role in carcinogenesis in general and HNSCC in particular. The identification of five novel mutations suggest that Saudis may have different frequencies of somatic genetic alterations that may influence HNSCC compared to other populations.

In vitro evaluation of human hybrid cell lines generated by fusion of B-lymphoblastoid cells and ex vivo tumour cells as candidate vaccines for haematological malignancies.

Fusions of dendritic cells (DCs) and tumour cells have been shown to induce protective immunity to tumour challenge in animal models, and to represent a promising approach to cancer immunotherapy. The broader clinical application of this approach, however, is potentially constrained by the lack of replicative capacity and limited standardisation of fusion cell preparations. We show here that fusion of ex vivo tumour cells isolated from patients with a range of haematological malignancies with the human B-lymphoblastoid cell line (LCL), HMy2, followed by chemical selection of the hybridomas, generated stable, self-replicating human hybrid cell lines that grew continuously in tissue culture, and survived freeze/thawing cycles. The hybrid cell lines expressed HLA class I and class II molecules, and the major T-cell costimulatory molecules, CD80 and CD86. All but two of 14 hybrid cell lines generated expressed tumour-associated antigens that were not expressed by HMy2 cells, and were therefore derived from the parent tumour cells. The hybrid cell lines stimulated allogeneic T-cell proliferative responses and interferon-gamma release in vitro to a considerably greater degree than their respective parent tumour cells. The enhanced T-cell stimulation was inhibited by CTLA4-Ig fusion protein, and by blocking antibodies to MHC class I and class II molecules. Finally, all of five LCL/tumour hybrid cell lines tested induced tumour antigen-specific cytotoxic T-cell responses in vitro in PBL from healthy, HLA-A2+ individuals, as detected by HLA-A2-peptide pentamer staining and cellular cytotoxicity. These data show that stable hybrid cell lines, with enhanced immunostimulatory properties and potential for therapeutic vaccination, can be generated by in vitro fusion and chemical selection of B-LCL and ex vivo haematological tumour cells.

Long-lived fusions of human haematological tumour cells and B-lymphoblastoid cells induce tumour antigen-specific cytotoxic T-cell responses in vitro.

Tumour-specific cytotoxic T-cells (CTL) are important anti-cancer immune effectors. Most tumour cells, however, do not stimulate effective anti-tumour immune responses, in vivo or in vitro. To enhance tumour cell immunogenicity, we fused human tumour cells from haematological malignancies with the B-lymphoblastoid cell line (LCL), HMy2, to generate a panel of long-lived, self replicating LCL/tumour hybrid cell lines. The LCL/tumour hybrid cell lines expressed HLA class I and class II molecules, CD80 and CD86, and a range of known tumour associated antigens (TAAs). In vitro stimulation of PBLs from healthy, HLA-A2+ individuals by hybrid cell lines induced tumour antigen-specific CTLs to TAAs, including survivin, MAGE-A1, NY-ESO-1 and WT-1. Individual hybrid cell lines simultaneously induced CTL to multiple TAAs. In vitro stimulation of PBL from 2 patients with acute myeloid leukaemia by autologous LCL/tumour hybrid cell lines induced CTL capable of killing the patient's own tumour cells. Our data show, for the first time, that hybrid cell lines formed by fusion of HMy2 cells and haematological tumour cells induce tumour- and tumour antigen-specific cytotoxic T-cell responses in vitro. Hybrid cell lines such as those described may represent novel reagents for use in the immunotherapy of haematological malignancies.