Cell Antigen Research Articles

Standard Compared With Extended Red Blood Cell Antigen Matching for Prevention of Subsequent Hemolytic Disease of the Fetus and Newborn: A Systematic Review.

To systematically review and meta-analyze alloimmunization among recipients of red blood cells (RBCs) matched for ABO blood type and Rhesus D (ABO+D) antigen compared with those also matched for c, E, and Kell (cEK). Four online databases (Medline, Scopus, EMBASE, ClinicalTrials.gov) were searched from March 28, 2023, to April 1, 2024. The search protocol was peer reviewed and published on PROSPERO (CRD42023411620). Studies reporting alloimmunization as the primary outcome among recipients of RBCs matched for ABO+D or additional cEK matching were included. Patients transfused with unmatched RBCs or a mixture of matching regimens were excluded. Risk of bias was assessed with Cochrane Tool to Assess Risk of Bias in Cohort Studies and Tool for Risk of Bias. Random-effects meta-analysis was used to combine effect estimates. Ten studies met criteria. Risk of bias was low. Overall, 91,221 patients were transfused, of whom 40,220 (44.1%) received additional cEK-matched RBCs. The overall rate of alloimmunization was 6.2% (95% CI, 2.5-14.9%) for ABO+D-only matching and 1.9% (95% CI, 0.7-5.1%) when cEK was added. Time of follow-up antibody testing ranged from 6 to 18 months after transfusion. Additional cEK match was associated with significantly less alloimmunization compared with standard ABO+D match (odds ratio [OR] 0.37, 95% CI, 0.20-0.69). This association remained when chronically transfused patients were excluded (OR 0.65, 95% CI, 0.54-0.79) and for alloimmunization to c, E, or K antigens only (OR 0.29, 95% CI, 0.18-0.47). Additional cEK RBC matching protocols were associated with lower odds of recipient alloimmunization. Given severe sequelae of alloimmunization in pregnancy, routine cEK matching for transfusion in people with pregnancy potential younger than age 50 years in the United States merits consideration. PROSPERO, CRD42023411620.

The tandem CD33-CLL1 CAR-T as an approach to treat acute myeloid leukemia.

Acute myeloid leukemia (AML) is characterized by high heterogeneity, poor long-term survival, and a propensity for relapse. Exceptional efficacy in treating recurrent or refractory B-lymphoid malignancies has been demonstrated by Chimeric antigen receptor T cells (CAR-T cells). Given the therapeutic potential of targeting both CD33 and C-type lectin-like molecule-1 (CLL1) in AML, the development of a dual-targeting CD33-CLL1 CAR-T cells assumes significant importance. The expressions of CD33 and CLL-1 antigens in peripheral blood cells and bone marrow cells from AML patients was assessed. Subsequently, a Chimeric Antigen Receptor (CAR) incorporating a dual-specific single-chain variable fragment targeting CLL1 and CD33 (CD33-CLL1-CAR-T) was engineered. The anti-tumor efficacy and potential side effects of CD33-CLL1-CAR-T cells were comprehensively investigated in both in vitro and in vivo settings. The constructed tandem CD33-CLL1 CAR-T exhibited potent cytotoxicity against leukemia cell lines and human primary AML cells in vitro. Co-cultivation of AML blasts with CD33-CLL1-CAR-T cells resulted in effective proliferation and the secretion of substantial quantities of GM-CSF and IFN-γ. Importantly, the impact of CD33-CLL1-CAR-T cells on normal hematopoietic stem cells was minimal, ensuring safety in vivo mouse models. Notably, significant anti-leukemic activity was observed in the mouse model, with CD33-CLL1-CAR-T cells leading to tumor eradication and prolonged survival. The tandem CD33-CLL1 CAR-T cells not only efficiently eliminated AML blasts but also exhibited low cytotoxicity toward normal hematopoietic stem cells (HSCs). These findings underscore the potential clinical applicability of the tandem CD33-CLL1 CAR-T cells as an effective and safe treatment strategy for AML, representing a noteworthy advancement in the field of CAR-T cells therapy.

N-acetylgalactosaminyltransferase GALNT6 is a potential therapeutic target of clear cell renal cell carcinoma progression.

High expression of truncated O-glycans Tn antigen predicts adverse clinical outcome in patients with clear cell renal cell carcinoma (ccRCC). To understand the biosynthetic underpinnings of Tn antigen changes in ccRCC, we focused on N-acetylgalactosaminyltransferases (GALNTs, also known as GalNAcTs) known to be involved in Tn antigen synthesis. Data from GSE15641 profile and local cohort showed that GALNT6 was significantly upregulated in ccRCC tissues. The current study aimed to determine the role of GALNT6 in ccRCC, and whether GALNT6-mediated O-glycosylation aggravates malignant behaviors. Gain- and loss-of-function experiments showed that overexpression of GALNT6 accelerated ccRCC cell proliferation, migration, and invasion, as well as promoted ccRCC-derived xenograft tumor growth and lung metastasis. In line with this, silencing of GALNT6 yielded the opposite results. Mechanically, high expression of GALNT6 led to the accumulation of Tn antigen in ccRCC cells. By undertaking immunoprecipitation coupled with liquid chromatography/mass spectrometry, vicia villosa agglutinin blot, and site-directed mutagenesis assays, we found that O-glycosylation of prohibitin 2 (PHB2) at Ser161 was required for the GALNT6-induced ccRCC cell proliferation, migration, and invasion. Additionally, we identified lens epithelium-derived growth factor (LEDGF) as a key regulator of GALNT6 transcriptional induction in ccRCC growth and an upstream contributor to ccRCC aggressive behavior. Collectively, our findings indicate that GALNT6-mediated abnormal O-glycosylation promotes ccRCC progression, which provides a potential therapeutic target in ccRCC development.

Monocyte/Macrophage-Mediated Transport of Dual-Drug ZIF Nanoplatforms Synergized with Programmed Cell Death Protein-1 Inhibitor Against Microsatellite-Stable Colorectal Cancer.

Microsatellite-stable colorectal cancer (MSS-CRC) exhibits resistance to programmed cell death protein-1 (PD-1) therapy. Improving the infiltration and tumor recognition of cytotoxic T-lymphocytes (CTLs) is a promising strategy, but it encounters huge challenges from drug delivery and mechanisms aspects. Here, a zeolitic imidazolate framework (ZIF) coated with apoptotic body membranes derived from MSS-CRC cells is engineered for the co-delivery of ginsenoside Rg1 (Rg1) and atractylenolide-I (Att) to MSS-CRC, named as Ab@Rg1/Att-ZIF. This system is selectively engulfed by Ly-6C+ monocytes during blood circulation and utilizes a "hitchhiking" mechanism to migrate toward the core of MSS-CRC. Ab@Rg1/Att-ZIF undergoes rapid disassembly in the tumor, released Rg1 promotes the processing and transportation of tumor antigens in dendritic cells (DCs), enhancing their maturation. Meanwhile, Att enhances the activity of the 26S proteasome complex in tumor cells, leading to increased expression of major histocompatibility complex class-I (MHC-I). These coordinated actions enhance the infiltration and recognition of CTLs in the center of MSS-CRC, significantly improving the tumor inhibition of PD-1 treatment from ≈5% to ≈69%. This innovative design, involving inflammation-guided precise drug co-delivery and a rational combination, achieves synergistic engineering of the tumor microenvironment, providing a novel strategy for successful PD-1 treatment of MSS-CRC.

Quantifying T cell receptor mechanics at membrane junctions using DNA origami tension sensors.

The T cell receptor (TCR) is thought to be a mechanosensor, meaning that it transmits mechanical force to its antigen and leverages the force to amplify the specificity and magnitude of TCR signalling. Although a variety of molecular probes have been proposed to quantify TCR mechanics, these probes are immobilized on hard substrates, and thus fail to reveal fluid TCR-antigen interactions in the physiological context of cell membranes. Here we developed DNA origami tension sensors (DOTS) which bear force sensors on a DNA origami breadboard and allow mapping of TCR mechanotransduction at dynamic intermembrane junctions. We quantified the mechanical forces at fluid TCR-antigen bonds and observed their dependence on cell state, antigen mobility, antigen potency, antigen height and F-actin activity. The programmability of DOTS allows us to tether these to microparticles to mechanically screen antigens in high throughput using flow cytometry. Additionally, DOTS were anchored onto live B cells, allowing quantification of TCR mechanics at immune cell-cell junctions.

Immunomodulatory activity of ovotransferrin-chlorogenic acid complexes enhanced by high-intensity ultrasound (HIU): A structure-function relationship study

This study investigated the impact of high-intensity ultrasound (HIU) treatment on the physiochemical, conformational, and immunomodulatory activity of the OVT-CA complex, emphasizing the structure-function relationship. HIU treatment reduced particle size, improved dispersion, and increased electronegativity of the complex. It facilitated binding between OVT and CA, achieving a maximum degree of 45.22 mg/g CA grafting and reducing interaction time from 2 h to 15 min. HIU-induced cavitation and shear promoted the exposure of -SH and unfolding of OVT, leading to increased surface hydrophobicity of the complex and transformation of its structure from β-sheet to α-helix. Additionally, CA binds to OVT in the C-lobe region, and HIU treatment modulates the intermolecular forces governing the complex formation, particularly by reinforcing hydrogen bonding, hydrophobic interactions, and introducing electrostatic interactions. Furthermore, HIU treatment increased the immunomodulatory activity of the complex, which was attributed to complex structural changes facilitating enhanced cell membrane affinity, antigen recognition, and B-cell epitope availability. Hierarchical cluster and Pearson correlation analysis confirmed that HIU treatment duration had a greater impact than power on both the structure and activity of the complex, and an optimal HIU treatment duration within 30 min was found to be crucial for activity enhancement. Moreover, structural changes, including ζ-potential, particle size/turbidity, and surface hydrophobicity, were closely correlated with immunomodulatory activity. This study highlights the potential application of HIU in developing protein–polyphenol immunomodulatory agents for public health and food nutrition.

Harnessing the potential of blood donors negative for high prevalence Rh antigens: A database initiative for thalassaemia care

Background and objectivesWith increasing life expectancy and prevalence of thalassaemia, it has led to a greater need for safe blood, yet the current supply from voluntary donors is insufficient to meet this demand. Thalassaemia recipients face a significant risk of alloimmunization because of repeated exposure to foreign red cell antigens. Study aims to determine high prevalent Rh antigen negative donors in western India donor population along with what percentage of these donors are willing to become dedicated voluntary donors for thalassaemia patients. Study also aims to examine factors influencing their willingness and challenges faced in mobilizing dedicated donors. Method700 whole blood donors from western India, following screening for inclusion & exclusion criteria as per Drugs and Cosmetic Act (DCA) 2020 amendment guidelines & were sero-negative for transfusion transmitted infections were enrolled for the study. Red cell phenotyping was performed using Conventional Tube Technique (CTT) for “D”, “C”, “E”, “c”, “e” and “K” antigen using known antisera. Donors that were “C” AND/OR “e” antigen negative were contacted telephonically and were counseled and motivated for becoming voluntary blood donors. Statistical analysis assessed correlation between donation frequency, donor’s occupation and education. ResultAmong 700 donors, 96.6% (n = 676) were males and 3.4% (n = 24) were females. The most predominant blood group was B > O > A > AB. Rh(D) antigen was present in 91.44% (n = 640) and absent in 8.6% (n = 60). Prevalence of other Rh antigens is as follows: “e” (99%) > “C” (85.4%) > “c” (59.1%) > “E” (18.0%). Only 1.15% had “K” antigen positive. The commonest Rh phenotype R1R1 (DCe/DCe) was expressed by 40.57% (n = 283), and the least common r″r (cE/ce), r″r″ (cE/cE) and r′r′ (Ce/Ce) was found in 0.14% (n = 1), respectively. ‘C’ negative, ‘e’ negative, ‘C’ and ‘e’ antigen negative donors constituted 14.8% (n = 104) with 93.2% (n = 97) C-antigen negative, 1.92% (n = 2) e-antigen negative and 4.8% (n = 5) both “C” and “e” antigen negative donors. The commonest phenotypes among C-antigen and e-antigen negative donors were rr (50%) and RzR2 (1.94%) respectively. Likewise, the most common phenotype amongst both C- and e-antigens negative donors was R2R2 (3.84%). 61.5% of the donors agreed to enroll for voluntary blood donation following telephonic invitation, while 6.8% of them refused permanently. Approximately, 3.9% of the blood donors were willing to donate blood only when needed and 27.8% of them could not be contacted. ConclusionCreating a database of voluntary donors with known phenotype, especially who lack very common antigens like “C” and “e” and are willing to become dedicated, regular voluntary donors for thalassemic patients can ensure timely administration of safe blood. One of the major challenges for this noble initiative was lack of awareness which can be circumvent effectively with proper counseling efforts.

A CAR enhancer increases the activity and persistence of CAR T cells.

Although chimeric antigen receptor (CAR) T cell therapies have demonstrated promising clinical outcomes, durable remissions remain limited. To extend the efficacy of CAR T cells, we develop a CAR enhancer (CAR-E), comprising a CAR T cell antigen fused to an immunomodulatory molecule. Here we demonstrate this strategy using B cell maturation antigen (BCMA) CAR T cells for the treatment of multiple myeloma, with a CAR-E consisting of the BCMA fused to a low-affinity interleukin 2 (IL-2). This selectively induces IL-2 signaling in CAR T cells upon antigen-CAR binding, enhancing T cell activation and antitumor activity while reducing IL-2-associated toxicities. We show that the BCMA CAR-E selectively binds CAR T cells and increases CAR T cell proliferation, clearance of tumor cells and development of memory CAR T cells. The memory cells retain the ability to re-expand upon restimulation, effectively controlling tumor growth upon rechallenge. Mechanistic studies reveal the involvement of both CAR and IL-2 receptor endodomains in the CAR-E mechanism of action. The CAR-E approach avoids the need for specific engineering and enables CAR T cell therapy with lower cell doses.

Simultaneous targeting and monitoring of free antigen and in-situ membrane antigen in prostate cancer cells via an aggregation-induced emission-based bifunctional probe

The precise clinical diagnosis of prostate cancer still presents inherent challenges, and usually a monitoring of multiple biomarkers is required. In this study, a new aggregation-induced emission (AIE)-based bifunctional strategy was developed for the simultaneous detection of prostate cancer-specific in situ membrane antigens (PSMA) and free antigens (PSA). First, a bifunctional fluorescent probe with double sensing sites (a PSA-specific sensing site and a PSMA-targeted ligand) was constructed. In the presence of PSA, it specifically binds to the PSA-specific sensing site of the probe, resulting in the restoration of the fluorescence signal, enabling linear sensing of PSA. For the detection of PSMA, the PSMA-targeted ligand modified on the probe can specifically recognize PSMA, inducing the aggregation of the AIE material and resulting in an enhanced fluorescence signal. Moreover, a liposome-based artificial cell was developed to simulate the real prostate cancer cell, and it was used to investigate the feasibility of monitoring the two types of antigens. Utilizing this bifunctional fluorescent strategy, a dual-analysis of free serum antigen biomarker of PSA and in-situ membrane antigen of PSMA was achieved. The assay exhibited a wide linearity range for PSA detection from 0.0001 to 0.1 μg/mL, with a low limit of detection (LOD) of 6.18 pg/mL. For PSMA, the obtained LOD is 8.79 pg/mL, with a linearity range from 0.0001 to 0.1 μg/mL. This strategy allows us to simultaneously assess the levels of two types of biomarkers in living human prostatic cancer cells, providing a highly accurate and selective tool for early screening and monitoring of prostatic cancer.

Red blood cell alloimmunization in transfused patients with myelodysplastic syndromes: a retrospective study from northern China.

Alloimmunization against red blood cell (RBC) antigen is an important concern in myelodysplastic syndromes (MDSs) patients with chronic transfusion, causing potential risk for hemolytic reaction and limited supply of compatible blood. However, there is little data addressing RBC alloimmunization in this patient cohort among the Chinese population. This study aims to evaluate the incidence, specificity of antibodies, and RBC units transfused before antibody formation and its significance in a population of patients consistently receiving RhD-matched RBC units. We retrospectively reviewed the transfusion and clinical information of all transfused patients with MDS enrolled in our hospital from 2012 to 2022. The cumulative incidence of alloimmunization was analyzed by a Kaplan-Meier plot. Alloimmunization incidence was compared based on different transfused RBC units using the log-rank test. A total of 103 patients with MDS were included in this study; alloantibody formed in 8 (7.8%) patients. Before reaching 32 RBC units, 87.5% of the alloimmunized patients had developed their alloantibodies. All but 1 of the alloantibodies developed were antibodies to Rh antigens. The RBC transfusion intensity and frequency were significantly higher following alloimmunization in the alloimmunized patients (P=.008, P=.008, respectively). The antibodies detected mostly involve the Rh system among MDS patients in China. The alloimmunization tended to occur early prior to reaching 32 RBC units in patients with MDS. Rh antigen matching should be considered early in the patient's transfusion history and completed before receiving 32 RBC units.

Identifying and validating angiogenesis-related genes remodeling tumor microenvironment and suppressing immunotherapy response in gastric cancer

Angiogenesis significantly correlates with tumor microenvironment remodeling and immunotherapy response. Our study aimed to construct a prognostic angiogenesis-related model for gastric cancer. Using public database, a angiogenetic related five-gene (FGF1, GRB14, PAK3, PDGFRA, and PRKD1) model was identified. The top 25 % of patients were defined as high-risk, and the remaining as low-risk. The area under the curve for 1-, 3-, and 5-year overall survival (OS) were 0.646, 0.711, and 0.793, respectively. Survival analysis showed a better 10-year OS in low-risk patients in the construction (HR = 0.57, p = 0.002) and validation cohorts. GO and GSEA revealed that DEGs were enriched in extracellular matrix receptor interactions, dendritic cell antigen processing/presentation regulation, and angiogenesis pathways. CIBERSORT analysis revealed abundant naïve B cells, resting mast cells, resting CD4+ memory T cells, M2 macrophages, and monocytes in high-risk subgroups. The TIMER database showed strong positive correlations between PAK3, FGF1, PRKD1, and PDGFRA expression levels and the infiltration of CD4+ T cells and macrophages. The IOBR analysis revealed an immunosuppressive environment in the high-risk subgroup. Low-risk patients show a higher response rate to anti-PD1 treatment. TMA showed that FGF1 overexpression was associated with poor prognosis and CD4+ T cells and macrophage infiltration. In vivo study based on the 615 mice indicated that inhibiting FGF1 function could suppress tumor growth and enhance anti-PD1 therapeutic efficacy. In summary, we established a five-angiogenesis-related gene model to predict survival outcomes and immunotherapy responses in patients with gastric cancer and identified FGF1 as a prognostic gene and potential target for improving immune treatment.

Molecular mechanism of basolateral amygdala involved in electroacupuncture-induced amelioration of cancer pain and concomitant depression based on transcriptomics techniques.

To observe the effect of electroacupuncture (EA) of "Zusanli" (ST36) and "Sanyinjiao" (SP6) on cancer pain and concomitant negative emotion in cancer pain model mice, and to explore its molecular mechanisms in the basolateral amygdala (BLA) by using transcriptomics techniques. C57BL/6 mice were randomized into sham operation, model and EA groups, with 10 mice in each group. The cancer pain model was established by injecting PBS suspension containing Lewis lung cancer cells into the femur. The mice in the EA group received EA stimulation(1 mA, 2 Hz) on ST36 and SP6 from the 10th day after modeling, 20 min per day for 12 successive days. The bone damage of the distal femur was observed with X-ray and H.E. staining, respectively. The mechanical pain threshold (MPT) was detected by using von Frey. The depression-like behavior was detected by using sucrose-preference test (sucrose preference index in 12 h), and the immobility (feeling of despair) duration of forced swimming within 4 min. The BLA tissue was extracted for RNA sequencing (RNA library construction, and screening differential gene profiling by transcriptomic sequencing) and bioinformatics analysis. The real-time PCR was used to validate the mRNA expression of differentially expressed genes：tumor necrosis factor superfamily 8 (Tnfsf8), bone marrow stromal cell antigen 1 (Bst1), prodynorphin (Pdyn) and voltage-gated sodium channelβ4 (Scn4b). H.E. staining and X-ray showed significant bone damage in the distal femur in cancer pain mice. In contrast to the sham operation group, the MPT on the 1st , 4th, 7th , 10th, 14th and 21st day after modeling and sucrose preference index were significantly decreased (P<0.001, P<0.000 1), and the immobility time of the forced swimming was considerably increased in the model group (P<0.001). In contrast to the model group, the MPT values on the 14th and 21st day and sucrose preference index were obviously increased (P<0.000 1, P<0.05), and the immobility time was strikingly decreased in the EA group (P<0.01). RNA sequencing showed that a total of 404 differentially expressed genes (205 up-regulated, 199 down-regulated) were screened in the model group compared with the sham operation group, and a total of 329 differentially expressed genes (206 up-regulated and 123 down-regulated) were screened in the EA group compared with the model group. Venn diagram analysis of the differentially expressed genes showed that 45 up-regulated and 28 down-regulated genes in the model group were completely reversed by EA. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses of the screened differentially expressed genes revealed that the above differential genes were mainly enriched in the ligand receptor activity, cytokine receptor binding, and cytokine activity related to neuro-inflammation, as well as in neuropeptide signaling pathways related to neuronal excitability, and calcium ion mediated signal transduction. The analysis of KEGG pathway showed that the differentially expressed genes were mainly enriched in the inflammation-related pathways, such as interleukin-17 pathway. Validation analysis of the differentially expressed genes showed that the expression levels of Tnfsf8 and Bst1 were significantly up-regulated in the model group compared with the sham operation group (P<0.01, P<0.05), and down-regulated by EA (P<0.01, P<0.05), while the expression levels of Pdyn and Scn4b were down-regulated in the model group in comparison with the sham operation group (P<0.01), and up-regulated by EA (P<0.05, P<0.01), which was consistent with the changing trend of the gene sequencing results. Acupuncture of ST36 and SP6 can significantly relieve cancer pain and concomitant negative emotion in cancer pain mice, which may be related to its functions in alleviating neuro-inflammation and relieving the abnormal activities of specific neurons in the BLA.

Cell-Free DNA Analysis for the Determination of Fetal Red Blood Cell Antigen Genotype in Individuals With Alloimmunized Pregnancies.

To evaluate the accuracy of next-generation sequencing-based quantitative cell-free DNA analysis for fetal antigen genotyping in individuals with alloimmunized pregnancies undergoing clinical testing in practices across the United States as early as 10 weeks of gestation, with the objective of identifying individuals with pregnancies at risk for hemolytic disease of the fetus and newborn and guiding management. This prospective cohort study included patients with alloimmunized pregnancies undergoing clinical fetal antigen cell-free DNA analysis between 10 0/7 and 37 0/7 weeks of gestation at 120 clinical sites. Both the pregnant person with the alloimmunized pregnancy and the neonates resulting from the pregnancies were included. The laboratory issued the cell-free DNA results prospectively as a part of clinical care. After delivery, neonatal buccal swabs collected between 0 and 270 days of life were sent to an outside independent laboratory for antigen genotyping. The outside laboratory was blinded to the fetal cell-free DNA results, and the results were compared. Concordance was reported for the fetal antigen cell-free DNA analysis for antigens to which the pregnant person was alloimmunized and for all antigens for which the pregnant person was genotype negative. A total of 156 pregnant people who received clinically ordered cell-free DNA fetal antigen testing provided neonatal buccal swabs for genotyping after delivery. Overall, 15.4% of participants were Hispanic, 9.0% were non-Hispanic Black, 65.4% were non-Hispanic White, 4.5% were Asian, 1.3% were more than one race or ethnicity, and 4.5% were unknown. The median gestational age at the time of testing was 16.4 weeks with a median fetal fraction of 11.1%. Concordance between cell-free DNA analysis results and neonatal genotype was determined for 465 antigen calls for the following antigens: K1 (n=143), E (124), C (60), Fya (50), c (47), and D(RhD) (41). These 465 calls included 145 in which the fetus was antigen positive and 320 in which the fetus was antigen negative. We observed complete concordance between prenatal fetal antigen cell-free DNA analysis results and neonatal genotypes for the 465 calls, resulting in 100% sensitivity, specificity, and accuracy. In a diverse multicenter cohort, cell-free DNA analysis was highly sensitive and specific for determining fetal antigen genotype as early as 10 weeks of gestation in individuals with alloimmunized pregnancies. Taken together with previously published evidence, this study supports the implementation of cell-free DNA testing to manage individuals with alloimmunized pregnancies in the United States.

Lck Function and Modulation: Immune Cytotoxic Response and Tumor Treatment More Than a Simple Event.

Lck, a member of the Src kinase family, is a non-receptor tyrosine kinase involved in immune cell activation, antigen recognition, tumor growth, and cytotoxic response. The enzyme has usually been linked to T lymphocyte activation upon antigen recognition. Lck activation is central to CD4, CD8, and NK activation. However, recently, it has become clearer that activating the enzyme in CD8 cells can be independent of antigen presentation and enhance the cytotoxic response. The role of Lck in NK cytotoxic function has been controversial in a similar fashion as the role of the enzyme in CAR T cells. Inhibiting tyrosine kinases has been a highly successful approach to treating hematologic malignancies. The inhibitors may be useful in treating other tumor types, and they may be useful to prevent cell exhaustion. New, more selective inhibitors have been documented, and they have shown interesting activities not only in tumor growth but in the treatment of autoimmune diseases, asthma, and graft vs. host disease. Drug repurposing and bioinformatics can aid in solving several unsolved issues about the role of Lck in cancer. In summary, the role of Lck in immune response and tumor growth is not a simple event and requires more research.

Integrated Genome-Wide Analysis of DNA Methylation and Gene Expression in the Hippocampi of 5xFAD Alzheimer's Disease Mouse Model.

DNA methylation forms 5-methylcytosine and its regulation in the hippocampus is critical for learning and memory. Indeed, dysregulation of DNA methylation is associated with neurological diseases. Alzheimer's disease (AD) is the predominant of dementia and a neurodegenerative disorder. We examined the learning and memory function in 3- and 9-month-old wild-type and 5xfamiliar Alzheimer's disease (5xFAD) transgenic mice by performing the object recognition memory and Y-maze tests, and identified the hippocampal amyloid beta burden. To investigate the epigenetically regulated genes involved in the development or neuropathology of AD, we performed genome-wide DNA methylation sequencing and RNA sequencing analyses in the hippocampus of 9-month-old wild-type and 5xFAD tg mice. To validate the genes inversely regulated by epigenetics, we confirmed their methylation status and mRNA levels. At 9 months of age, 5xFAD tg mice showed significant cognitive impairment and amyloid-beta plaques in the hippocampus. DNA methylation sequencing identified a total of 13,777 differentially methylated regions, including 4484 of hyper- and 9293 of hypomethylated regions, that are associated with several gene ontology (GO) terms including 'nervous system development' and 'axon guidance'. In RNA sequencing analysis, we confirmed a total of 101 differentially expressed genes, including 52 up- and 49 downregulated genes, associated with GO functions such as 'positive regulation of synaptic transmission, glutamatergic' and 'actin filament organization'. Through further integrated analysis of DNA methylation and RNA sequencing, three epigenetically regulated genes were selected: thymus cell antigen 1, theta (Thy1), myosin VI (Myo6), and filamin A-interacting protein 1-like (Filip1l). The methylation level of Thy1 decreased and its mRNA levels increased, whereas that of Myo6 and Filip1l increased and their mRNA levels decreased. The common functions of these three genes may be associated with the neural cytoskeleton and synaptic plasticity. We suggest that the candidate genes epigenetically play a role in AD-associated neuropathology (i.e., amyloid-beta plaques) and memory deficit by influencing neural structure and synaptic plasticity. Furthermore, counteracting dysregulated epigenetic changes may delay or ameliorate AD onset or symptoms.

Rosmarinic acid turned α-syn oligomers into non-toxic species preserving microtubules in Raw 264.7 cells

Parkinson’s disease (PD) is the second most prevalent neurodegenerative disorder worldwide, and the therapeutic is focused on several approaches including the inhibition of fibril formation by small compounds, avoiding the formation of cytotoxic oligomers. Thus, we decided to explore the capacity of compounds carrying catechol moieties to inhibit the progression of α-synuclein. Overall, the compounds rosmarinic acid (1), carnosic acid (2), carnosol (3), epiisorosmanol (4), and rosmanol (5) avoid the progression of fibril formation assessed by Thiofavine T (ThT), and atomic force microscopy images showed that morphology is influenced for the actions of compounds over fibrillization. Moreover, ITC experiments showed a Kd varying from 28 to 51 µM, the ΔG showed that the reaction between compounds and α-syn is spontaneous, and ΔH is associated with an exothermic reaction, suggesting the interactions of hydrogen bonds among compounds and α-syn. Docking experiments reinforce this idea showing the intermolecular interactions are mostly hydrogen bonding within the sites 2, 9, and 3/13 of α-synuclein, and compounds 1 and 5. Thus, compound 1, rosmarinic acid, interestingly interacts better with site 9 through catechol and Lysines. In cultured Raw 264. 7 cells, the presence of compounds showed that most of them can promote cell differentiation, especially rosmarinic acid, and rosmanol, both preserving tubulin cytoskeleton. However, once we evaluated whether or not the aggregates pre-treated with compounds could prevent the disruption of microtubules of Raw 264.7 cells, only pre-treated aggregates with rosmarinic acid prevented the disruption of the cytoskeleton. Altogether, we showed that especially rosmarinic acid not only inhibits α-syn but stabilizes the remaining aggregates turning them into not-toxic to Raw 264.7 cells suggesting a main role in cell survival and antigen processing in response to external α-syn aggregates.

The CH1 domain influences the expression and antigen sensing of the HIV-specific CH31 IgM-BCR and IgG-BCR

How different classes of the B cell antigen receptor (BCR) sense viral antigens used in vaccination protocols is poorly understood. Here, we study antigen binding and sensing of human Ramos B cells expressing a BCR of either the IgM or IgG1 class with specificity for the CD4-binding-site of the envelope (Env) protein of the HIV-1. Both BCRs carry an identical antigen binding site derived from the broad neutralizing antibody (bnAb) CH31. We find a five times higher expression of the IgG1-BCR in comparison to the IgM-BCR on the surface of transfected Ramos B cells. The two BCR classes also differ from each other in their interaction with cognate HIV Env antigens in that the IgG1-BCR and IgM-BCR bind preferentially to polyvalent and monovalent antigens, respectively. By generating an IgM/IgG1 chimeric BCR, we found that the class-specific BCR expression and antigen-sensing behavior can be transferred with the CH1γ domain from the IgG1-BCR to the IgM-BCR. Thus, the class of CH1 domain has an impact on BCR assembly and expression as well as on antigen sensing.

Deep mutational scanning reveals transmembrane features governing surface expression of the B cell antigen receptor.

B cells surveil the body for foreign matter using their surface-expressed B cell antigen receptor (BCR), a tetrameric complex comprising a membrane-tethered antibody (mIg) that binds antigens and a signaling dimer (CD79AB) that conveys this interaction to the B cell. Recent cryogenic electron microscopy (cryo-EM) structures of IgM and IgG isotype BCRs provide the first complete views of their architecture, revealing that the largest interaction surfaces between the mIg and CD79AB are in their transmembrane domains (TMDs). These structures support decades of biochemical work interrogating the requirements for assembly of a functional BCR and provide the basis for explaining the effects of mutations. Here we report a focused saturating mutagenesis to comprehensively characterize the nature of the interactions in the mIg TMD that are required for BCR surface expression. We examined the effects of 600 single-amino-acid changes simultaneously in a pooled competition assay and quantified their effects by next-generation sequencing. Our deep mutational scanning results reflect a feature-rich TMD sequence, with some positions completely intolerant to mutation and others requiring specific biochemical properties such as charge, polarity or hydrophobicity, emphasizing the high value of saturating mutagenesis over, for example, alanine scanning. The data agree closely with published mutagenesis and the cryo-EM structures, while also highlighting several positions and surfaces that have not previously been characterized or have effects that are difficult to rationalize purely based on structure. This unbiased and complete mutagenesis dataset serves as a reference and framework for informed hypothesis testing, design of therapeutics to regulate BCR surface expression and to annotate patient mutations.

Emerging Indications for Neoadjuvant Systemic Therapies in Cutaneous Malignancies.

Patients with cutaneous malignancies and locoregional involvement represent a high-risk population for disease recurrence, even if they receive optimal surgery and adjuvant treatment. Here, we discuss how neoadjuvant therapy has the potential to offer significant advantages over adjuvant treatment, further improving outcomes in some patients with skin cancers, including melanoma, Merkel cell carcinoma, and cutaneous squamous-cell carcinoma. Both preclinical studies and in vivo trials have demonstrated that exposure to immunotherapy prior to surgical resection can trigger a broader and more robust immune response, resulting in increased tumor cell antigen presentation and improved targeting by immune cells, potentially resulting in superior outcomes. In addition, neoadjuvant approaches hold the possibility of providing a platform for evaluating pathological responses in the resected lesion, optimizing the prognosis and enabling personalized adaptive management, in addition to expedited drug development. However, more data are still needed to determine the ideal patient selection and the best treatment framework and to identify reliable biomarkers of treatment responses. Although there are ongoing questions regarding neoadjuvant treatment, current data support a paradigm shift toward considering neoadjuvant therapy as the standard approach for selecting patients with high-risk skin tumors.

Morphological and Immunocytochemical Characterization of Paclitaxel-Induced Microcells in Sk-Mel-28 Melanoma Cells.

Biomarkers, including proteins, nucleic acids, antibodies, and peptides, are essential for identifying diseases such as cancer and differentiating between healthy and abnormal cells in patients. To date, studies have shown that cancer stem cells have DNA repair mechanisms that deter the effects of medicinal treatment. Experiments with cell cultures and chemotherapy treatments of these cultures have revealed the presence of small cells, with a small amount of cytoplasm that can be intensively stained with azure eosin, called microcells. Microcells develop during sporosis from a damaged tumor macrocell. After anticancer therapy in tumor cells, a defective macrocell may produce one or more microcells. This study aims to characterize microcell morphology in melanoma cell lines. In this investigation, we characterized the population of cancer cell microcells after applying paclitaxel treatment to a Sk-Mel-28 melanoma cell line using immunocytochemical cell marker detection and fluorescent microscopy. Paclitaxel-treated cancer cells show stronger expression of stem-associated ALDH2, SOX2, and Nanog markers than untreated cells. The proliferation of nuclear antigens in cells and the synthesis of RNA in microcells indicate cell self-defense, promoting resistance to applied therapy. These findings improve our understanding of microcell behavior in melanoma, potentially informing future strategies to counteract drug resistance in cancer treatment.