Human Lymphocytes Research Articles

In silico and pharmacological evaluation of GPR65 as a cancer immunotherapy target regulating T-cell functions.

The success of cancer immunotherapies such as immune checkpoint inhibitors, CAR T-cells and immune cell engagers have provided clinicians with tools to bypass some of the limitations of cancer immunity. However, numerous tumour factors curtail the immune response against cancer and limit the efficiency of immuno-oncology (IO) therapies. Acidification of the extra-cellular tumour environment consecutive to aberrant cancer cell metabolism is a well-known promoter of oncogenic processes that also acts as an immune regulator. Yet, the suppressive mechanisms of low extra-cellular pH on anti-cancer immunity remain poorly understood. Recent reports have suggested that GPR65, a Gαs-coupled proton-sensing GPCR broadly expressed in the immune system, may act as an immune suppressant detrimental to anti-tumour immunity. So far, the immuno-regulatory properties of GPR65 in acidic milieux have mostly been documented in macrophages and myeloid cells. Our computational evaluation of GPR65's transcriptomic expression profile and potential as an IO target using public datasets prompted us to further investigate its functions in human T-cells. To this end, we identified and validated GPR65 small molecule inhibitors active in in vitro cellular assays and we showed that GPR65 inhibition promoted the killing capacity of antigen-specific human T-cells. Our results broaden the scope of GPR65 as an IO target by suggesting that its inhibition may enhance T-cell anti-tumour activity and provide useful pharmacological tools to further investigate the therapeutic potential of GPR65 inhibition.

Effect of CAT gene polymorphism on sensitivity of human lymphocytes to genotoxic effect of organochlorine pesticide in vitro

Introduction. Over recent decades, toxicogenetic studies have focused on the issues of genome instability under the action of genotoxicants, taking into account biomarkers of sensitivity. The question about the genotoxic potential of chlorpyrifos remains open, since both positive and negative effects have been revealed in various tests. The aim of the study is the investigation of sensitivity of donor peripheral blood lymphocytes to chlorpyrifos in vitro and evaluation of the contribution of polymorphism of antioxidant defense system genes (CAT (rs1001179), SOD2 (rs4880)) to the response of human cells to the action of genotoxicant. Materials and methods. The DNA damaging effect of chlorpyrifos was assessed on lymphocytes from fifty two donors using DNA-comet assay with metabolic activation (+S9) and without it (–S9). The study of cytotoxic effects of chlorpyrifos on human lymphocytes was carried out using an automatic fluorescent cell analyzer ADAMII LS. Results. Chlorpyrifos had a pronounced cytotoxic effect on lymphocytes in most donors in the absence of metabolic activation system. With increasing concentration of the pesticide in the medium and time of cultivation, the viability of lymphocytes decreased, and the proportion of cells in late apoptosis and necrosis increased. Positive genotoxic effects were found on the cells of 33 donors (-S9). In the presence of the S9, mild but statistically significant effects were detected only on cells from 2 donors. % DNA values in the comet tail after exposure to the pesticide varied for cells from different donors. In the absence of metabolic activation, a statistically significant increase in the level of DNA damage was found in cells of individuals with genotype AA (homozygote for the minor allele) for the CAT G262A catalase gene (rs1001179), compared with homozygote for the dominant GG allele. Limitations. The genotoxicity of chlorpyryfos was studied in vitro. Conclusion. The results of the study shown cytotoxic and genotoxic effects of chlorpyrifos. The sensitivity of lymphocytes from different donors to the pesticide was found to be significantly different. The association of the level of DNA damage under exposure of chlorpyrifos in vitro with the G262A polymorphism of the catalase gene was found. The research also confirms the possibility of using a model test-system with peripheral blood lymphocytes to assess the potential genetic risk for humans and to study the contribution of gene polymorphism to individual sensitivity to the action of genotoxicants.

MQ232, A Snake Toxin Derivative for Treatment of Hyponatremia and Polycystic Kidney Diseases

Background: Vaptans were developed at the end of the previous century as V2R antagonists. Tolvaptan is the most prescribed vaptan for hyponatremia and the autosomal polycystic kidney disease (ADPKD). However, its use is not as widespread as it should be due to price issues, a narrow therapeutic window and some side effects. With the aim of discovering new efficient and safer V2R antagonists, we screened animal venoms and identified several interesting peptide toxins. Among them, MQ1 displayed such unique biological properties in that regard that it was the starting point for the development of a potential drug candidate. Methods: Human T-cell assays and bioinformatics was used to mitigate MQ1 immunogenicity risk. The MQ232 biodistribution in mice was done by positron emission tomography (PET). Pharmacodynamics, pharmacokinetics, acute and chronic toxicity tests were performed on control rats. A rat experimental model of dDAVP-induced hyponatremia, an ex vivo mice model of renal cysts and a mice orthologous model of ADPKD were used to validate MQ232 efficacy in these pathologies. Results: Three mutations were introduced in MQ1 to mitigate its immunogenicity risk. A fourth gain-of-function mutation was added to generate MQ232. MQ232’s safety was demonstrated by a first toxic dose as high as 3,000 nmol/kg and a strong kidney organ selectivity by PET imaging, while showing almost no interaction with the liver. MQ232’s efficacy was first demonstrated with an effective dose of 3 nmol/kg in a hyponatremic model, and then in polycystic kidney models on which MQ232 significantly reduced cyst growth. Conclusions: We demonstrated, employing diverse translational techniques and minimizing animal use, MQ232's safety and efficacy in several rodent models of hyponatremia and ADPKD.

Long-Term Human Immune Reconstitution, T-Cell Development, and Immune Reactivity in Mice Lacking the Murine Major Histocompatibility Complex: Validation with Cellular and Gene Expression Profiles.

Humanized mice transplanted with CD34+ hematopoietic cells (HPCs) are broadly used to study human immune responses and infections in vivo and for testing therapies pre-clinically. However, until now, it was not clear whether interactions between the mouse major histocompatibility complexes (MHCs) and/or the human leukocyte antigens (HLAs) were necessary for human T-cell development and immune reactivity. We evaluated the long-term (20-week) human hematopoiesis and human T-cell development in NOD Scid Gamma (NSG) mice lacking the expression of MHC class I and II (NSG-DKO). Triplicate experiments were performed with HPCs obtained from three donors, and humanization was confirmed in the reference strain NOD Rag Gamma (NRG). Further, we tested whether humanized NSG-DKO mice would respond to a lentiviral vector (LV) systemic delivery of HLA-A*02:01, HLA-DRB1*04:01, human GM-CSF/IFN-α, and the human cytomegalovirus gB antigen. Human immune reconstitution was detectable in peripheral blood from 8 to 20 weeks after the transplantation of NSG-DKO. Human single positive CD4+ and CD8+ T-cells were detectable in lymphatic tissues (thymus, bone marrow, and spleen). LV delivery harnessed the detection of lymphocyte subsets in bone marrow (αβ and γδ T-cells and NK cells) and the expression of HLA-DR. Furthermore, RNA sequencing showed that LV delivery increased the expression of different human reactome pathways, such as defense responses to other organisms and viruses. Human T-cell development and reactivity are independent of the expression of murine MHCs in humanized mice. Therefore, humanized NSG-DKO is a promising new model for studying human immune responses, as it abrogates the xenograft mouse MHC interference.

Large and small extracellular vesicles from Wharton’s jelly MSCs: Biophysics, function, and strategies to improve immunomodulation

Extracellular vesicles (EVs) have emerged as mediators of immunosuppression and pro-regenerative processes, particularly through mesenchymal stromal cells (MSCs) across various disease models. Despite significant progress, there is still a need for a deeper understanding of EV content and functionality to fully harness their biomedical potential. Moreover, strategies to enhance EV production for clinical scalability are still under development. This study aimed to characterize two distinct types of EV-large EV (lgEV) and small EV (smEV)-secreted by Wharton's jelly MSCs (WJ-MSCs). Strategies were explored to augment both EV production and their immunoregulatory effects. Both lgEV and smEV displayed typical EV markers and demonstrated inhibition of human lymphocyte proliferation. Furthermore, analysis of IsomiR content revealed a pronounced immunomodulating signature within MSC-derived EVs, validated by a dual-fluorescence reporter system. MSC primed with pro-inflammatory cytokines yielded increased production of lgEV and smEV, enhancing their immunomodulatory potency. Finally, genetically engineering WJ-MSC to express CD9 resulted in lgEV and smEV with heightened efficacy in suppressing lymphocyte proliferation. This study successfully isolated, characterized, and demonstrated the potent immunosuppressive effect of WJ-MSC-derived lgEV and smEV. We propose cytokine preconditioning and genetic manipulation as viable strategies to enhance the therapeutic potential of WJ-MSC-derived EV in inflammatory conditions.

In Vitro and In Vivo Genotoxicity of Polystyrene Microplastics: Evaluation of a Possible Synergistic Action with Bisphenol A.

The ubiquitous presence of plastics represents a global threat for all ecosystems and human health. In this study, we evaluated, in vitro and in vivo, the genotoxic potential of different concentrations of polystyrene microplastics (PS-MPs) and their possible synergistic interactions with bisphenol-A (BPA). For the in vitro and the in vivo assays, we used human lymphocytes and hemocytes from Lymnaea stagnalis, respectively. The genomic damage was evaluated by the micronucleus assay, and differences in eggs laid and growth of L. stagnalis were also evaluated. In human lymphocytes, PS-MPs alone at the concentration of 200 μg/mL and in association with BPA 0.100 µg/mL significantly increased the frequencies of micronuclei and nuclear buds, indicating a possible in vitro genotoxic additive action of these two compounds. Vice versa, PS-MPs did not result in genotoxicity in hemocytes. Our results indicated that PS-MPs have genotoxic properties only in vitro and at a concentration of 200 µg/mL; moreover, this compound could intensify the genomic damage when tested with BPA, indicating possible cumulative effects. Finally, PS significantly reduced the growth and the number of laid eggs in L. stagnalis.

8090 A Gut Commensal, Parabacteroides distasonis, and Molecular Mimicry in Type 1 Diabetes

Abstract Disclosure: A. Randall: None. Type 1 diabetes (T1D) is a chronic autoimmune disease characterized by the destruction of pancreatic, insulin-producing beta cells by autoreactive T-cells. The trigger(s) of T1D are unclear and genetics alone cannot explain the recent increase in T1D incidence. The gut microbiome composition in T1D patients is altered and thought to play a key role in T1D pathogenesis. Most longitudinal studies have been descriptive. However, a direct cause-and-effect relationship hasn't been established yet. Insulin is a key autoantigen in T1D autoimmunity, and insulin B-chain amino acids 9-23 (insB:9-23) is an important, commonly recognized T-cell epitope. Molecular mimicry is an autoimmunity mechanism where host-like microbial proteins trigger autoimmune responses. We previously identified a peptide mimic of insB:9-23, amino acids 4-18 of hypoxanthine phosphoribosyl transferase (HPRT:4-18) of Parabacteroides distasonis (Girdhar et al., 2022). HPRT:4-18 stimulated insB:9-23-specific human and non-obese diabetic (NOD) mice T-cells. We hypothesize that P. distasonis HPRT:4-18 is required to accelerate diabetes via molecular mimicry of insB:9-23. By orally gavaging NOD mice (n=40 mice/group), we showed that P. distasonis accelerated diabetes onset. Next, we colonized NOD mice with another common gut commensal, Bacteroides fragilis, as a control, and did not observe any effect on islet infiltration. In addition, P. distasonis colonization increased infiltration of immune cells into the islets of germ-free NOD mice (n=6-8 mice/group), while the diabetes incidence experiment in mice is ongoing. P. distasonis-colonized mice had significantly more splenic CD8 and naïve T-cells, dendritic cells and macrophages but fewer FOXP3 cells (n=3-6 mice/group). To determine whether P. distasonis’s effect is specific to the pancreas, we checked intestinal barrier function and intestinal immune cell composition. Disruption of intestinal barrier function has been associated with diabetes. P. distasonis colonization did not alter gut permeability. Furthermore, P. distasonis did not increase intestinal inflammation. Among the intestinal intraepithelial lymphocytes (IELs), there were fewer naïve, central and effector T-cells and B-cells. The findings indicate that P. distasonis does not stimulate an unspecific immune response and its inflammatory effect is specific to the pancreas, supporting our initial hypothesis. Taken together, our results indicate that exposure to P. distasonis in the first years of life has the potential to stimulate molecular mimicry mechanism and cause T1D onset. Reference: Girdhar, K., Huang, Q., Chow, I. T., Vatanen, T., Brady, C., Raisingani, A., . . . Altindis, E. (2022). A gut microbial peptide and molecular mimicry in the pathogenesis of type 1 diabetes. Proc Natl Acad Sci U S A, 119(31), e2120028119. doi:10.1073/pnas.2120028119 Presentation: 6/2/2024

6529 The Risk of Hypophysitis Following Treatment With Relatlimab+Nivolumab Appears Higher Than Expected

Abstract Disclosure: N. Chamorro-Pareja: None. A.T. Faje: None. K.K. Miller: Stock Owner; Self; Bristol-Myers Squibb. Hypophysitis is a recognized complication of immune checkpoint inhibitor therapy; the risk of developing hypophysitis in patients receiving nivolumab (an anti-programmed death-ligand 1 [anti-PD-1]) is estimated to be < 1%. Relatlimab is a human monoclonal antibody targeting lymphocyte activation gene 3 (LAG-3) recently approved in combination with nivolumab for the treatment of unresectable or metastatic melanoma. The risk of hypophysitis as a complication of relatlimab therapy is not well-defined. Objective: To examine the prevalence, identify risk factors, and characterize the clinical presentation of hypophysitis in patients receiving relatlimab+nivolumab. Methods: 159 patients received relatlimab+nivolumab at the Mass General Brigham health care system between 6/2015 and 11/2023. Twenty-seven patients were excluded because they were either diagnosed with adrenal insufficiency (AI) before receiving relatlimab+nivolumab or AI was secondary to other factors, primarily exogenous glucocorticoid administration, leaving a total of 122 patients. The medical records of these patients, including provider encounters, laboratory results, medication records, and radiologic images were reviewed. Data are presented as mean ± SD. Results: Central AI was diagnosed in 10 patients (7.5% of the cohort) after relatlimab+nivolumab administration. The mean age was 64.5±13.8 vs. 67.1±14.4 in patients with AI vs. patients without AI (p= 0.58). Sixty percent of patients in the AI group were male compared to 53% of patients without AI (p= 0.68). The development of AI was not related to the cumulative dose of relatlimab+nivolumab (mean number of cycles 6.4±3.2 vs. 4.9±5.0, p=0.35). The most common presenting symptoms of AI were fatigue, anorexia, nausea, and vomiting. No patients were diagnosed with additional anterior pituitary hormone deficiencies, though not all patients were evaluated for these diagnoses; none had diabetes insipidus. Nine patients had MRIs performed after the diagnosis of central AI; 7 of these patients had pre-treatment MRIs for comparison. Diffuse pituitary enlargement was seen on MRI after initiation of relatlimab+nivolumab in 3 patients up to 8 weeks prior to the diagnosis of hypopituitarism. All patients had persistent hypopituitarism at the most recent evaluation. Conclusions: This study is the first cohort analysis of hypophysitis in patients treated with relatlimab+nivolumab. A significant portion of patients were diagnosed with central AI, presumptively due to hypophysitis given the lack of an identifiable alternative etiology. Although the clinical phenotype of these patients paralleled published studies analyzing anti-PD-1 monotherapy, combination treatment with relatlimab+nivolumab appeared to confer a significantly higher risk of developing hypophysitis. Presentation: 6/3/2024

Cognitive Assessment in HTLV-1 Patients Followed Up at a Reference Center in Salvador, Brazil.

Human T-cell lymphotropic virus type 1 (HTLV-1) is endemic to Brazil, and there is still no specific treatment for these patients. The literature shows that few studies have described the cognitive impairment associated with an HTLV-1 infection, with none of them examining the population of Salvador, where there are approximately forty thousand people infected with the virus. To determine the prevalence of cognitive impairment among individuals with HTLV-1. In addition, investigate whether sociodemographic aspects, time since the diagnosis of infection, and the diagnosis of HTLV-Associated Myelopatia/Tropical Spastic Paraparesis (HAM/TSP) or depression are associated with cognitive impairment in this population. This was an observational, cross-sectional study that consisted of consecutively approaching 100 HTLV-1 patients during outpatient care at a referral center followed by the administration of three questionnaires- the Mini Mental State Examination (MMSE), the Montreal Cognitive Assessment (MoCA), and Beck's Depression Inventory. The prevalence of cognitive impairment found was 71% using the MMSE and 82% using the MoCA. There was a statistically significant association between the cognitive dysfunction and the variables of age and education according to the MoCA analysis but not the MMSE data. Diagnosis of HAM/TSP was correlated with cognitive impairment using the MMSE but not the MoCA. The prevalence of depression was 20%, and there was no association between cognitive impairment and depressive symptoms in these patients. The findings of this study demonstrate a correlation between cognitive dysfunction and HTVL-1 infection, with a more evident involvement of executive functions and memory. Larger studies are needed to clarify the association between cognitive dysfunction, age, education, and the diagnosis of HAM/TSP.

Lack of SMARCB1 expression characterizes a subset of human and murine peripheral T-cell lymphomas

Peripheral T-cell lymphoma, not otherwise specified (PTCL-NOS) is a heterogeneous group of malignancies with poor outcome. Here, we identify a subgroup, PTCL-NOSSMARCB1-, which is characterized by the lack of the SMARCB1 protein and occurs more frequently in young patients. Human and murine PTCL-NOSSMARCB1- show similar DNA methylation profiles, with hypermethylation of T-cell-related genes and hypomethylation of genes involved in myeloid development. Single-cell analyses of human and murine tumors revealed a rich and complex network of interactions between tumor cells and an immunosuppressive and exhausted tumor microenvironment (TME). In a drug screen, we identified histone deacetylase inhibitors (HDACi) as a class of drugs effective against PTCL-NOSSmarcb1-. In vivo treatment of mouse tumors with SAHA, a pan-HDACi, triggered remodeling of the TME, promoting replenishment of lymphoid compartments and reversal of the exhaustion phenotype. These results provide a rationale for further exploration of HDACi combination therapies targeting PTCL-NOSSMARCB1- within the TME.

A20 intrinsically influences human effector T-cell survival and function by regulating both NF-κB and JNK signaling.

A20 is a dual-function ubiquitin-editing enzyme that maintains immune homeostasis by restraining inflammation. Although A20 serves a similar negative feedback function for T-cell receptor (TCR) signaling, the molecular mechanisms utilized and their ultimate impact on human T-cell function remain unclear. TCR engagement triggers the assembly of the CARD11-BCL10-MALT1 (CBM) protein complex, a signaling platform that governs the activation of downstream transcription factors including NF-κB and c-Jun/AP-1. Utilizing WT and A20 knockout Jurkat T cells, we found that A20 is required to negatively regulate NF-κB and JNK. Utilizing a novel set of A20 mutants in NF-κB and AP-1-driven reporter systems, we discovered the ZnF7 domain is crucial for negative regulatory capacity, while deubiquitinase activity is dispensable. Successful inactivation of A20 in human primary effector T cells congruently conferred sustained NF-κB and JNK signaling, including enhanced upregulation of activation markers, and increased secretion of several cytokines including IL-9. Finally, loss of A20 in primary human T cells resulted in decreased sensitivity to restimulation-induced cell death and increased sensitivity to cytokine withdrawal-induced death. These findings demonstrate the importance of A20 in maintaining T-cell homeostasis via negative regulation of both NF-κB and JNK signaling.

Successful generation of fully human, second generation, anti-CD19 CAR T cells for clinical use in patients with diverse autoimmune disorders

BackgroundB-cell targeting chimeric antigen receptor (CAR) T-cell therapies, which lead to profound B-cell depletion, have been well-established in hematology-oncology. This deep B-cell depletion mechanism has prompted the exploration of their use in B-cell driven autoimmune diseases. We herein report on the manufacturing of KYV-101, a fully human anti-CD19 CAR T-cell therapy, derived from patients who were treated across a spectrum of autoimmune diseases. MethodsKYV-101 was manufactured from peripheral blood-derived mononuclear cells of 20 patients across 7 autoimmune disease types (neurological autoimmune diseases, n=13; rheumatological diseases, n=7). Patients ranged from 18–75 years of age. Duration of disease ranged from <1–23 years since diagnosis. Patients were heavily pretreated, and most were refractory to prior immunosuppressive treatments. Apheresis was collected across 9 sites, cryopreserved, and shipped to the manufacturing facility. Healthy donor apheresis samples were collected for manufacturing comparison. Manufacturing was performed using the CliniMACS Prodigy system. Cells were enriched for CD4+/CD8+ T cells, transduced with a 3rd generation lentiviral vector encoding the CAR, expanded in vitro, and harvested. Percent cell viability, T-cell purity, cellular expansion, and transduction efficiency were assessed. Activity was assessed using cytokine release assays for KYV-101 CAR T cells co-cultured with different CD19+/– target cell lines. ResultsKYV-101 was successfully manufactured for 100% of patients. Transduced cell populations were highly viable, with expansion ranging from 11–66 fold at Day 8, and were comparable across disease types. Healthy donor-derived controls displayed similar expansion ranges. High CAR expression and transduction rates were observed, ranging between 37–84% with low variation in transgene copy number (2 to 4 per cell). Cell viability of the final KYV-101 drug product ranged from 87–97%. KYV-101 displayed robust CD19-dependent and effector dose-related release of the pro-inflammatory cytokine IFN-γ. ConclusionsKYV-101 manufacturing yielded a CAR T-cell product with high viability and consistent composition and functionality, regardless of disease indication, pre-treatment, and heterogeneity of the incoming material. Cryopreservation of the apheresis and final drug product enabled widespread distribution. These results support the robustness of the manufacturing process for the fully human KYV-101 anti-CD19 CAR T-cell therapy drug product for patients across diverse autoimmune disease types.

Evaluation of thiopyrano[2,3-d]thiazole derivatives as potential anticonvulsant agents.

Anticonvulsant drug discovery has achieved significant progress; however, pharmacotherapy of epilepsy continues to be a challenge for modern medicine and pharmacy. To expand the chemical space of heterocycles as potential antiepileptic agents, herein we report on the synthesis and evaluation of anticonvulsant properties of a series of thiopyrano[2,3-d]thiazoles. The studied heterocycles are characterized by satisfactory drug-likeness and pharmacokinetics properties, calculated in silico using SwissADME. The anticonvulsant activity of thiopyrano[2,3-d]thiazole derivatives was evaluated in vivo using the subcutaneous pentylenetetrazole test. Three hits, that is, compounds 12, 14, and 16, that caused a pronounced anticonvulsant effect were identified. Derivatives 12, 14, and 16 positively affected the latent period of onset of clonic seizures, number of seizures, mortality rate, and duration of the seizure period of animals under experimental conditions. The anticonvulsant properties of compound 14 were equivalent to the effect of the reference drug, sodium valproate. All hit compounds are characterized by satisfying toxicity properties in the human lymphocytes and HEK293 cell line. The most active hit 14 possesses a potential affinity with the GABAA receptor in the molecular docking study and forms a stable complex in the molecular dynamics experiments equal to diazepam. Preliminary SAR results were obtained and discussed based on screening data.

Structure Of The Single Health System For Diagnosis Of Htlv-1/2 In The Northern Region Of Tocantins

Background: The Human T-cell Lymphotropic Virus (HTLV), the first human retrovirus discovered, is associated with oncogenesis and is subdivided into several groups, with types 1 and 2 being the most prevalent and clinically relevant. Its main forms of transmission include unprotected sexual intercourse, blood transfusions, tissue and organ transplants, as well as vertical transmission (mother to newborn). In Brazil, mandatory testing for HTLV was implemented in the 1990s for blood donations and transplants, and expanded in 2024 by Ordinance No. 3,148 of the Ministry of Health, which includes testing during prenatal care. Objective: This study aimed to evaluate the structure of the Unified Health System (SUS) in the municipalities of the far north of Tocantins for the diagnosis of HTLV-1/2. Methodology: This is a qualitative study, in which semi-structured questionnaires were applied to Primary Care professionals and municipal health managers. Results: The results indicated significant deficiencies in knowledge of national protocols and the absence of a structured municipal flow for testing. Conclusion: It can be concluded that the health structure of the municipalities evaluated is insufficient for the effective diagnosis of HTLV-1/2

Sexual transmission of HTLV-1 resulting in uveitis with short-term latency and low proviral load.

Human T-cell Lymphotropic Virus Type 1 (HTLV-1) is traditionally linked to severe conditions such as adult T-cell leukemia/lymphoma, HTLV-1-associated myelopathy, and HTLV-1 uveitis, with vertical transmission, particularly mother to child thorough breastfeeding, considered the primary route. Despite efforts to reduce vertical transmission through antenatal screening in Japan, horizontal transmission has contributed to the rising prevalence of HTLV-1 in metropolitan areas. This case reports the youngest documented instance of HTLV-1 uveitis resulting from horizontal transmission through sexual contact in an 18-year-old woman. The patient presented with blurred vision in her right eye, and a comprehensive ophthalmologic examination identified vitreous opacity and retinal vasculitis. Serological tests confirmed HTLV-1 infection, with a proviral load of 2.66 copies per 100 peripheral blood mononuclear cells, measured by real-time PCR. A differential diagnosis confirmed HTLV-1 uveitis. Further family and partner investigations confirmed horizontal transmission, most likely through sexual contact. Over 6 years of follow-up, the patient experienced multiple recurrences of HTLV-1 uveitis and developed HTLV-1-associated keratopathy. This case highlights the potential for rapid disease progression with relatively low proviral loads and short latency, emphasizing the need for updated public health strategies for sexually active young populations.

267 - Darifenacin versus Parasacral Transcutaneous Electrical Nerve Stimulation for Overactive Bladder Syndrome in Patients Infected With Human T-Cell Lymphotropic Virus 1 – Preliminary Results of a Randomized Clinical Trial

267 - Darifenacin versus Parasacral Transcutaneous Electrical Nerve Stimulation for Overactive Bladder Syndrome in Patients Infected With Human T-Cell Lymphotropic Virus 1 – Preliminary Results of a Randomized Clinical Trial

Targeting HLA-E-overexpressing cancers with a NKG2A/C switch receptor

Human leukocyte antigen (HLA)-E is overexpressed by a large proportion of solid tumors, including malignant glioblastoma, and acts as a major checkpoint for NKG2A+ CD8+ Tcells and natural killer (NK) cells in the tumor microenvironment and circulation. This axis operates alongside PD-L1 to inhibit effector responses by T and NK cells. We engineered a chimeric A/C switch receptor, combining the high HLA-E binding affinity of the NKG2A receptor ectodomain with the activating signaling of the NKG2C receptor endodomain. The cytotoxic function of A/C switch-transduced NK and Tcells was evaluated against tumor cells with varying levels of HLA-E expression. Invivo efficacy was assessed using a xenograft model of glioblastoma. A/C switch-transduced NK and Tcells exhibited superior and specific cytotoxicity against tumor cells with medium to high HLA-E expression. A/C switch-expressing human Tcells demonstrated enhanced anti-tumor function in a glioblastoma xenograft model. The activity of the modified Tcells was governed by an equilibrium between A/C switch levels and HLA-E expression, creating a therapeutic window to minimize on-target, off-tumor toxicities. Normal cells remained insensitive to A/C switch Tcells, even after interferon (IFN)-γ pretreatment to induce HLA-E expression. The A/C switch receptor effectively targets tumor cells expressing high levels of HLA-E, either alone or in combination with other engineered specificities, to overcome the suppressive NKG2A/HLA-E checkpoint. This approach offers a promising therapeutic strategy with a favorable safety profile for targeting HLA-E-overexpressing tumors. This work was funded by The Research Council of Norway, the Norwegian Cancer Society, and the National Cancer Institute.

Effect of diode pumping solid state laser with wavelength 589 nm on gene expression of interlukine-2 and interferon-γ in human T-lymphocytes.

To evaluate the impact of laser irradiation of human T-cell lymphocyte in culture to determine the photobiomodulatory effects of such irradiation on gene expression, and the release of growth factors and cytokines. The experimental study was conducted from November 2021 to April 2022 at the Postgraduate Anatomy Laboratory, Mustansiriyah University, Baghdad, Iraq, and comprised human blood samples T-cell lymphocytes were extracted and irradiated, followed by the extraction of ribonucleic acid to assess the effect of laser on gene expression of cytokines, interlukine-2 and interferon-gamma. A 589nm yellow light low-level laser beam from a diode pumping solid state laser was used at doses 30J/cm2, 50J/cm2 and 70J/cm2 for an exposure time of 15 minutes. Reverse transcriptase-polymerase chain reaction was used to measure gene expression. Data was analysed using GraphPad Prism 9. Cellular gene expression of the mediators changed significantly in response to laser irradiation at a variety of dosage parameters, and these effects depended on the wavelength and radiation exposure (p<0.05). The laser light may photobiomodulate the production of cytokines by human cells in vitro.

The Adsorption of Chlorpromazine on the Surface of Gold Nanoparticles and Its Effect on the Toxicity to Selected Mammalian Cells

Chlorpromazine (CPZ) is a first-generation neuroleptic with well-established antitumor and antiviral properties. Currently, numerous studies are focused on developing new methods for CPZ delivery; however, the knowledge regarding its conjugates with metal nanoparticles remains limited. The aim of this study was to prepare CPZ conjugates with gold nanoparticles (AuNPs) and evaluate their biological activity on human lymphocytes (HUT-78 and COLO 720L), as well as human (COLO 679) and murine (B16-F0) melanoma cells, in comparison to the effects induced by unconjugated CPZ molecules and AuNPs with well-defined properties. During the treatment of cells with CPZ, AuNPs, and CPZ-AuNP conjugates, changes in mitochondrial activity, membrane integrity, and the secretion of lipid peroxidation mediators were studied using standard biological assays such as MTT, LDH, and MDA assays. It was found that positively charged CPZ-AuNP conjugates more effectively reduced cell viability compared to AuNPs alone. The dose-dependent membrane damage was correlated with oxidative stress resulting from exposure to CPZ-AuNP conjugates. The activity of the conjugates depended on their composition and the size of the AuNPs. It was concluded that conjugating CPZ to AuNPs reduced its biological activity, while the cellular response to the treatment varied depending on the specific cell type.

Evaluation of the effect of yellow laser (DPSS) light on human lymphocytes viability in vitro.

To evaluate the lymphocyte apoptotic impact of yellow laser light in vitro. The experimental study was conducted from November 2021 to April 2022 at the Postgraduate Medical Physics Laboratory, Mustansiriyah University, Baghdad, Iraq, and comprised blood samples from healthy volunteers. The samples were subjected to 1:1 dilution in isotonic phosphate buffered saline, and each sample was divided into two equal aliquots; one for irradiation, and other as control.The percentage of apoptotic lymphocyte was estimated before and after radiation exposure with low-level laser 589nm at 30J/cm², 50J/cm² and 70J/cm² energy intensities. Post-exposure evaluation was done immediately, and 1 and 2 hours after radiation on the viability of normal human cells. The vitality of the cells was determined using the trypan blue exclusion test. Data was analysed using SPSS 24. There were 26 healthy volunteers (16 male, 10 females) with an age range of (20-40) years. After the exposure, the percentage of lymphocytes that apoptose increased significantly when cells were irradiated at 70J/cm2 immediately compared to the controls (p≤ 0.05), but there was no significant differences with the 30J/cm² dose. After 1 and 2 hours, a significant reduction in the proportion of apoptotic lymphocytes was observed (p<0.05). Yellow low-level laser showed a noticeable protective effect on lymphocytes by decreasing the percentage of dead cells.