暂无摘要。

Objective: To analyze the sensitivity of cytoplasmic light-chain immunofluorescence with fluorescence in situ hybridization in bone marrow smears (new FISH) for detecting cytogenetic abnormalities in multiple myeloma (MM) . Methods: 42 MM patients admitted to the First Affiliated Hospital of Nanjing Medical University from April 2022 to October 2023 were enrolled. The patients with MM were detected by new FISH and CD138 immunomagnetic bead sorting technology combined with FISH (MACS-FISH) or cytoplasmic immunoglobulin FISH (cIg-FISH) to analyze cytogenetic detection results using combination probes which included 1q21/1p32, p53, IgH, IgH/FGFR3 [t (4;14) ], and IgH/MAF [t (14;16) ]. Results: In 23 patients with MM, the abnormality detection rates of cIg-FISH and new FISH were 95.7% and 100.0%, respectively (P>0.05). The detection rates of 1q21+, 1p32-, p53 deletion, and IgH abnormalities by cIg-FISH and new FISH were consistent, which were 52.2%, 8.7%, 17.4%, and 65.2%, respectively. The results of the two methods further performed with t (4;14) and t (14;16) in patients with IgH abnormalities were identical. The positive rate of t (4;14) was 26.7%, whereas t (14;16) was not detected. In 19 patients with MM, the abnormality detection rates of MACS-FISH and new FISH were 73.7% and 63.2%, respectively (P>0.05). The positivity rate of 1q21+, 1p32- and IgH abnormalities detected by MACS-FISH were slightly higher than those detected by new FISH; however, the differences were not statistically significant (all P values >0.05) . Conclusion: The new FISH method has a higher detection rate of cytogenetic abnormalities in patients with MM and has good consistency with MACS-FISH and cIg-FISH.
目的： 分析骨髓涂片胞质轻链免疫荧光结合FISH技术（New-FISH）检测多发性骨髓瘤（MM）细胞遗传学异常的敏感性。 方法： 纳入南京医科大学第一附属医院2022年4月至2023年10月收治的42例MM患者，采用组合探针1q21/1p32、p53、IgH、IgH/FGFR3[t（4;14）]、IgH/MAF[t（14;16）]对患者同时进行New-FISH和CD138磁珠分选结合FISH（MACS-FISH）或胞质轻链免疫荧光结合FISH（cIg-FISH）检测，分析其细胞遗传学检测结果。 结果： 23例MM患者中，cIg-FISH法、New-FISH法异常检出率分别为95.7%、100.0%（P>0.05）。cIg-FISH法、New-FISH法对1q21扩增、1p32缺失、p53缺失、IgH异常的检出率一致，分别为52.2%、8.7%、17.4%、65.2%。进一步对IgH异常的患者进行t（4;14）、t（14;16）检测，t（4;14）阳性率为26.7%，t（14;16）未检出，两种方法检测结果相同。19例MM患者中，MACS-FISH法、New-FISH法异常检出率分别为73.7%、63.2%（P>0.05）。MACS-FISH法对1q21扩增、1p32缺失、IgH异常的检出率略高于New-FISH法，但差异均无统计学意义（P值均>0.05）。 结论： New-FISH法对于MM患者细胞遗传学异常检出率较高，与MACS-FISH、cIg-FISH一致性较好。.

UNASSIGNED: This scoping review and meta-analysis aimed to map the evidence regarding prognostic factors in Chinese patients with immunoglobulin light chain (AL) amyloidosis and to identify current research gaps.
UNASSIGNED: We searched EMBASE, PubMed, and CNKI databases from their inception to 15 September 2021. All studies investigated the association between any prognostic factor and target outcomes, including overall survival (OS), progression-free survival (PFS), and end-stage renal disease (ESRD) in Chinese patients with AL amyloidosis.
UNASSIGNED: This scoping review included 52 studies, of which 44 with 6,432 patients contributed to the multivariate prognostic analysis. Multivariate analysis identified a total of 106 factors that correlated with OS, 16 factors with PFS, and 18 factors with ESRD. Five prognostic factors were significantly associated with PFS, and 11 prognostic factors were significantly associated with ESRD. Meta-analysis was only available for prognostic factors without heterogeneous cutoff values, for which hazard ratios (HRs) and their 95% confidence intervals (CIs) were reported. Meta-analysis showed that bone marrow plasma cells (BMCs) (HR: 1.96, 95% CI: 1.21-3.19, p < 0.05) and interventricular septal thickness (IVST) (HR: 1.23, 95% CI: 1.10-1.38, p < 0.05) were independently associated with OS.
UNASSIGNED: The significant prognostic factors associated with OS, PFS, and ESRD in Chinese patients with AL amyloidosis were related to plasma cell tumor load, biological characteristics, cardiac involvement, renal involvement, population characteristics, and treatment. Further studies should explore additional prognostic factors in patients with AL amyloidosis to develop prognostic models.
The significant prognostic factors associated with OS, PFS, and ESRD in Chinese patients with AL amyloidosis were related to plasma cell tumor load, biological characteristics, cardiac involvement, renal involvement, population characteristics, and treatment.Meta-analysis showed there was a significant association between BMCs or interventricular septal thickness and OS.

Current guidelines recommend screening with serum M-protein and serum-free light chain analysis (S-FLC) when an M-protein-related disorder is suspected. Many patients with multiple myeloma will be overlooked if only serum M-protein is measured. Despite this, the general practitioners in some areas of Denmark cannot order S-FLC. This review aims to disseminate knowledge of the S-FLC analysis, its applicability, and limitations in the diagnostic workup for suspected monoclonal gammopathies.

BACKGROUND: Positron emission tomography/computed tomography (PET/CT) with 18F-florbetapir, a novel amyloid-targeting radiotracer, can quantify left ventricular (LV) amyloid burden in systemic light-chain (AL) amyloidosis. However, its prognostic value is not known.
OBJECTIVE: The authors\' aim was to evaluate the prognostic value of LV amyloid burden quantified by 18F-florbetapir PET/CT, and to identify mechanistic pathways mediating its association with outcomes.
METHODS: A total of 81 participants with newly diagnosed AL amyloidosis underwent 18F-florbetapir PET/CT imaging. Amyloid burden was quantified using 18F-florbetapir LV uptake as percent injected dose. The Mayo stage for AL amyloidosis was determined using troponin T, N-terminal pro-B-type natriuretic peptide (NT-proBNP), and free light chain levels. Major adverse cardiac events (MACE) were defined as all-cause death, heart failure hospitalization, or cardiac transplantation within 12 months.
RESULTS: Among participants (median age, 61 years; 57% males), 36% experienced MACE, increasing from 7% to 63% across tertiles of LV amyloid burden (P < 0.001). LV amyloid burden was associated with MACE (HR: 1.46; 95% CI: 1.16-1.83; P = 0.001). However, this association became nonsignificant when adjusted for Mayo stage. In mediation analysis, the association between LV amyloid burden and MACE was mediated by NT-proBNP (P < 0.001), a marker of cardiomyocyte stretch and heart failure, and a component of Mayo stage.
CONCLUSIONS: In this first study to link cardiac 18F-florbetapir uptake to subsequent outcomes, LV amyloid burden estimated by percent injected dose predicted MACE in AL amyloidosis. This effect was not independent of Mayo stage and was mediated primarily through NT-proBNP. These findings provide novel insights into the mechanism linking myocardial amyloid deposits to MACE.

Many researchers are interested in the possibility of manipulating the targeting specificity of extracellular vesicles (EVs) for their use as physiological delivery vehicles for drugs and bioactive molecules. Our studies demonstrated the possibility of directing EVs toward the desired acceptor cell by coating them with antigen-specific antibody light chains. Here, we describe the methods for detection of the presence of antibody light chains on the EV surface, proving their ability to specifically bind the antigen and for separating the antigen-binding EV subpopulation.

The ATP-dependent RNA helicase UPF1 plays a crucial role in various mRNA degradation pathways, most importantly in nonsense-mediated mRNA decay (NMD). Here, we show that UPF1 is upregulated during the early stages of B cell development and is important for early B cell development in the bone marrow. B-cell-specific Upf1 deletion in mice severely impedes the early to late LPre-B cell transition, in which VH-DHJH recombination occurs at the Igh gene. Furthermore, UPF1 is indispensable for VH-DHJH recombination, without affecting DH-JH recombination. Intriguingly, the genetic pre-arrangement of the Igh gene rescues the differentiation defect in early LPre-B cells under Upf1 deficient conditions. However, differentiation is blocked again following Ig light chain recombination, leading to a failure in development into immature B cells. Notably, UPF1 interacts with and regulates the expression of genes involved in immune responses, cell cycle control, NMD, and the unfolded protein response in B cells. Collectively, our findings underscore the critical roles of UPF1 during the early LPre-B cell stage and beyond, thus orchestrating B cell development.

UNASSIGNED: Cardiac involvement in systemic light chain amyloidosis (AL) leads to chronic heart failure and is a major prognosis factor. Severe cellular defects are provoked in cardiac cells by tissue-deposited amyloid fibrils of misfolded free immunoglobulin light chains (LCs) and their prefibrillar oligomeric precursors.
UNASSIGNED: Understanding the molecular mechanisms behind cardiac cell cytotoxicity is necessary to progress in therapy and to improve patient management. One key question is how extracellularly deposited molecules exert their toxic action inside cardiac cells. Here we searched for direct evidence of amyloid LC uptake by cardiomyocytes in patient biopsies.
UNASSIGNED: We immunolocalized LCs in cardiac biopsies from four AL cardiac amyloidosis patients and analysed histopathological images by high resolution confocal microscopy and 3D image reconstruction.
UNASSIGNED: We show, for the first time directly in patient tissue, the presence of LCs inside cardiomyocytes, and report their proximity to nuclei and to caveolin-3-rich areas. Our observations point to macropinocytosis as a probable mechanism of LC uptake.
UNASSIGNED: Internalisation of LCs occurs in patient cardiomyocytes. This event could have important consequences for the pathogenesis of the cardiac disease by enabling interactions between amyloid molecules and cellular organelles inducing specific signalling pathways, and might bring new insight regarding treatment.

Bispecific antibodies expressed and assembled from a single upstream culture require the correct balance and pairing of four different heavy and light chains (HC and LC). The increased potential for chain-mispaired species challenges the downstream purification of this new format. While clearance of HC-mispaired species, including homodimers and half-antibodies, has been assessed, removal of LC mispairs requires a more stringent approach. Here, we report two case studies in which separation is achieved, as well as the structural basis of these separations: (A) In the first case, a main species with a positively charged patch in the correctly formed variable fragment (Fv) is disrupted when paired with the wrong LC. This LC-mispaired variant binds more weakly to a cation exchange resin and can be washed off in a chromatography step. (B) A second molecule whose LC mispair introduces a negative-charge patch and hydrophobic patch in close proximity, presenting increased binding to a multimodal anion exchange resin. This LC-mispaired variant can be retained on the column under conditions in which the bispecific is recovered. In both case studies, the molecular structural analysis by protein surface properties models correlated well with the chromatography experiments. The comprehensive interpretation of experimental and computational results has provided a better understanding of strategies and potential applications for predicting the downstream purification of complex molecules.

According to classical immunology theory, immunoglobulin (Ig) is exclusively produced by differentiated B lymphocytes, which exhibit a typical tetrapeptide chain structure and are predominantly present on the surface of B cells and in bodily fluids. B-Ig is one of the critical effector molecules for humoral immune responses specifically recognising antigens and eliminating them. However, mounting evidence has demonstrated that Ig is widely expressed in non B lineage cells, especially malignant ones (referred to as non B-Ig). Interestingly, non B-Ig mainly resides in the cytoplasm and secretion, but to some extent on the cell surface. Furthermore non B-Ig not only displays a tetrapeptide chain structure but also shows free heavy chains and free light chains (FLCs). Additionally, Ig derived from non B cancer cell typically displays unique glycosylation modifications. Functionally, non B-Ig demonstrated diversity and versatility, showing antibody activity and cellular biological activity, such as promoting cell proliferation and survival, and it is implicated in cancer progression and some immune-related diseases, such as renal diseases.