Understanding the pairing preferences and structural interactions between antibody heavy and light chains can enhance our ability to design more effective and specific therapeutic antibodies. Insights from natural antibody repertoires and conserved contact sites help reduce autoreactivity and improve drug safety and efficacy. Current databases represent only a limited portion of the estimated diversity of unique paired antibody molecules. To address this, we introduce PairedAbNGS, a novel database with paired heavy/light antibody chains. To our knowledge, this is the largest resource for paired natural antibody sequences with 58 bioprojects and over 14 million assembled productive sequences. Using this dataset, we investigated heavy and light chain variable (V) gene pairing preferences and found significant biases beyond gene usage frequencies, possibly due to receptor editing favoring less autoreactive combinations. Analyzing the available antibody structures from the Protein Data Bank, we studied conserved contact residues between heavy and light chains, particularly interactions between the CDR3 region of one chain and the FWR2 region of the opposite chain. Examination of amino acid pairs at key contact sites revealed significant deviations of amino acids distributions compared to random pairings, in the heavy chain’s CDR3 region contacting the opposite chain, indicating specific interactions might be crucial for proper chain pairing. This observation is further reinforced by preferential IGHV-IGLJ and IGLV-IGHJ pairing preferences. We hope that both our resources and the findings would contribute to improving the engineering of biological drugs. We make the database accessible at https://naturalantibody.com/paired-ab-ngs as a valuable tool for biological and machine-learning applications.

Transarterial chemoembolization (TACE) is used as a bridging treatment in liver transplant candidates with hepatocellular carcinoma (HCC). Alpha-fetoprotein (AFP) is the main tumor marker used for HCC surveillance. The aim of this study was to assess the potential of using the AFP change after the first TACE in the prediction of complete tumor necrosis. The study comprised 101 patients with HCC who underwent liver transplantation (LT) after TACE in the period between January 2011 and December 2020. The ΔAFP was defined as the difference between the AFP value before the first TACE and AFP either before the second TACE or the LT. The receiver operator characteristics (ROC) curves were used to identify an optimal cut-off value. Complete tumor necrosis was found in 26.1% (18 of 69) and 6.3% (2 of 32) of patients with an initial AFP level under and over 100 ng/mL, respectively (p = 0.020). The optimal cut-off value of ΔAFP for the prediction of complete necrosis was a decline of ≥10.2 ng/mL and ≥340.5 ng/mL in the corresponding subgroups. Complete tumor necrosis rates were: 62.5% (5 of 8) in patients with an initial AFP < 100 ng/mL and decline of ≥10.2 ng/mL; 21.3% (13 of 61) in patients with an initial AFP < 100 ng/mL and decline of 100 ng/mL and decline of ≥340.5 ng/mL; and null in 20 patients with an initial AFP > 100 ng/mL and decline of <340.5 ng/mL, respectively (p = 0.003). The simple scoring system, based on the initial AFP and AFP decline after the first treatment, distinguished between a high, intermediate and low probability of complete necrosis, with an area under the ROC curve of 0.699 (95% confidence intervals 0.577 to 0.821, p = 0.001). Combining the initial AFP with its change after the first treatment enables early identification of the efficacy of TACE.

Background: Malignant and benign neuroendocrine tumors (NET) share many histopathological features. Liver transplantation (LT) is one of the liver-directed therapies for neuroendocrine liver metastases (NELM). The aim of this study was to determine the outcomes of patients undergoing LT for NELM. Material/Methods: This was a retrospective study that included 19 patients who underwent LT for unresectable NELM between December 1989 and December 2022 in the Department of General, Transplant, and Liver Surgery of the Medical University of Warsaw. Kaplan-Meier estimator and Cox proportional hazards regression were used for statistical analyses.Results: The primary tumor was located most frequently in the pancreas. The median follow-up was 72.5 months. The overall survival (OS) was 94.7%, 88.0%, 88.0%, 70.4%, and 49.3% after 1, 3, 5, 10, and 15 years, respectively. Accordingly, the recurrence-free survival (RFS) rates were 93.8%, 72.9%, 64.8%, 27.8%, and 27.8% after 1, 3, 5, 10, and 15 years, respectively. Ki-67 index >= 5% was found as a risk factor for both worse OS (hazard ratio (HR) 7.13, 95% confidence intervals (95% CI) 1.32-38.63, P=0.023) and RFS (HR 13.68, 95% CI 1.54-121.52, P=0.019). Recipient age >= 55 years was a risk factor for worse RFS (P=0.046, HR 5.47, 95% CI 1.03-29.08). Multivariable analysis revealed Ki-67 >= 5% as the sole independent factor for worse OS (HR 13.78, 95% CI 1.48-128.56, P=0.021).Conclusions: Patients with unresectable NELM achieve great OS and satisfying RFS after LT. The risk factors associated with worse outcomes are attributed to primary tumor aggressiveness.

Background/Objectives: Familial hyperaldosteronism type IV (FH-IV) is an extremely rare, clinically heterogeneous condition representing the least characterized familial subtype of primary aldosteronism (PA) caused by germline gain-of-function CACNA1H mutations. Despite growing molecular insights, optimal diagnostic and therapeutic strategies remain poorly defined. This systematic review aims to synthesize available evidence regarding the clinical, biochemical, and genetic characteristics of FH-IV, and to evaluate the efficacy of current pharmacological and surgical treatments. Methods: A systematic review was conducted in accordance with PRISMA guidelines and preregistered in PROSPERO (CRD420261324945). A comprehensive search of MEDLINE, Embase, and Web of Science identified studies reporting genetically confirmed FH-IV patients. Data concerning clinical phenotypes, diagnostic evaluations, treatment outcomes, and genetic backgrounds were extracted and analyzed. Results: The primary cohort included 31 fully characterized symptomatic patients, alongside 8 mutation-positive relatives (4 asymptomatic carriers and 4 symptomatic individuals). The genetic landscape was remarkably heterogeneous, encompassing 17 distinct CACNA1H mutations. Clinically, diagnosis was frequently delayed, often complicated by atypical normokalaemic presentations and misleading adrenal imaging. Surgical treatment was generally ineffective, frequently resulting in persistent or recurrent hypertension and biochemical dysregulation. Pharmacologically, patients often required multiple antihypertensive drugs, most frequently a combination of mineralocorticoid receptor antagonists (MRAs) and calcium channel blockers (CCBs). Conclusions: FH-IV is best conceptualized as a systemic adrenal channelopathy. While standard screening parameters are usually elevated, atypical biochemical profiles and misleading structural imaging can complicate the diagnostic process. Optimal management relies on multigene Next-Generation Sequencing (NGS) panels for definitive diagnosis and cascade screening of relatives. Finally, while the combination of MRAs and CCBs is commonly used in PA, it represents a valuable therapy for FH-IV, with dual L-/T-type CCBs emerging as a potential disease-specific option.