An Automated and Fast Sample Preparation Workflow for Laser Microdissection Guided Ultrasensitive Proteomics.

Spatial tissue proteomics integrating whole-slide imaging, laser microdissection, and ultrasensitive mass spectrometry is a powerful approach to link cellular phenotypes to functional proteome states in (patho)physiology. To be applicable to large patient cohorts and low sample input amounts, including single-cell applications, loss-minimized and streamlined end-to-end workflows are key. We here introduce an automated sample preparation protocol for laser microdissected samples utilizing the cellenONE robotic system, which has the capacity to process 192 samples in 3 h. Following laser microdissection collection directly into the proteoCHIP LF 48 or EVO 96 chip, our optimized protocol facilitates lysis, formalin de-crosslinking, and tryptic digest of low-input archival tissue samples. The seamless integration with the Evosep ONE LC system by centrifugation allows 'on-the-fly' sample clean-up, particularly pertinent for laser microdissection workflows. We validate our method in human tonsil archival tissue, where we profile proteomes of spatially-defined B-cell, T-cell, and epithelial microregions of 4000 µm2 to a depth of ∼2000 proteins and with high cell type specificity. We finally provide detailed equipment templates and experimental guidelines for broad accessibility.

Ultrasensitive and Multiplexed Protein Imaging with Clickable and Cleavable Fluorophores.

Single-cell spatial proteomic analysis holds great promise to advance our understanding of the composition, organization, interaction, and function of the various cell types in complex biological systems. However, the current multiplexed protein imaging technologies suffer from low detection sensitivity, limited multiplexing capacity, or are technically demanding. To tackle these issues, here, we report the development of a highly sensitive and multiplexed in situ protein profiling method using off-the-shelf antibodies. In this approach, the protein targets are stained with horseradish peroxidase (HRP) conjugated antibodies and cleavable fluorophores via click chemistry. Through repeated cycles of target staining, fluorescence imaging, and fluorophore cleavage, many proteins can be profiled in single cells in situ. Applying this approach, we successfully quantified 28 different proteins in human formalin-fixed paraffin-embedded (FFPE) tonsil tissue, which represents the highest multiplexing capacity among the tyramide signal amplification (TSA) methods. Based on their unique protein expression patterns and their microenvironment, ∼820,000 cells in the tissue are classified into distinct cell clusters. We also explored the cell-cell interactions between these varied cell clusters and observed that different subregions of the tissue are composed of cells from specific clusters.

Podoplanin depletion in tonsil-derived mesenchymal stem cells induces cellular senescence via regulation of the p16Ink4a/Rb pathway.

BACKGROUND: Mesenchymal stem cells (MSCs) are widely used in the development of therapeutic tools in regenerative medicine. However, their quality decreases during in vitro expansion because of heterogeneity and acquired cellular senescence. We investigated the potential role of podoplanin (PDPN) in minimizing cellular senescence and maintaining the stemness of tonsil-derived MSCs (TMSCs). METHODS: TMSCs were isolated from human tonsil tissues using an enzymatic method, expanded, and divided into two groups: early-passaged TMSCs, which were cultured for 3-7 passages, and late-passaged TMSCs, which were passaged more than 15 times. The TMSCs were evaluated for cellular senescence and MSC characteristics, and PDPN-positive and -negative cells were identified by fluorescence-activated cell sorting. In addition, MSC features were assessed in siRNA-mediated PDPN-depleted TMSCs. RESULTS: TMSCs, when passaged more than 15 times and becoming senescent, exhibited reduced proliferative rates, telomere length, pluripotency marker (NANOG, OCT4, and SOX2) expression, and tri-lineage differentiation potential (adipogenesis, chondrogenesis, or osteogenesis) compared to cells passaged less than five times. Furthermore, PDPN protein levels significantly decreased in a passage-dependent manner. PDPN-positive cells maintained their stemness characteristics, such as MSC-specific surface antigen (CD14, CD34, CD45, CD73, CD90, and CD105) and pluripotency marker expression, and exhibited higher tri-lineage differentiation potential than PDPN-negative cells. SiRNA-mediated silencing of PDPN led to decreased cell-cycle progression, proliferation, and migration, indicating the significance of PDPN as a preliminary senescence-related factor. These reductions directly contributed to the induction of cellular senescence via p16Ink4a/Rb pathway activation. CONCLUSION: PDPN may serve as a novel biomarker to mitigate cellular senescence in the clinical application of MSCs.

Oligoclonal CD4+CXCR5+ T cells with a cytotoxic phenotype appear in tonsils and blood.

In clinical situations, peripheral blood accessible CD3+CD4+CXCR5+ T-follicular helper (TFH) cells may have to serve as a surrogate indicator for dysregulated germinal center responses in tissues. To determine the heterogeneity of TFH cells in peripheral blood versus tonsils, CD3+CD4+CD45RA-CXCR5+ cells of both origins were sorted. Transcriptomes, TCR repertoires and cell-surface protein expression were analysed by single-cell RNA sequencing, flow cytometry and immunohistochemistry. Reassuringly, all blood-circulating CD3+CD4+CXCR5+ T-cell subpopulations also appear in tonsils, there with some supplementary TFH characteristics, while peripheral blood-derived TFH cells display markers of proliferation and migration. Three further subsets of TFH cells, however, with bona fide T-follicular gene expression patterns, are exclusively found in tonsils. One additional, distinct and oligoclonal CD4+CXCR5+ subpopulation presents pronounced cytotoxic properties. Those 'killer TFH (TFK) cells' can be discovered in peripheral blood as well as among tonsillar cells but are located predominantly outside of germinal centers. They appear terminally differentiated and can be distinguished from all other TFH subsets by expression of NKG7 (TIA-1), granzymes, perforin, CCL5, CCR5, EOMES, CRTAM and CX3CR1. All in all, this study provides data for detailed CD4+CXCR5+ T-cell assessment of clinically available blood samples and extrapolation possibilities to their tonsil counterparts.

Expression of Cyclin B1 and cdc2 in Nodal Non-Hodgkin's Lymphoma and its Prognostic Implications

To investigate the role of cyclin B1 and cdc2 in the pathogenesis and progression of malignant lymphoma, 68 cases of nodal non-Hodgkin's lymphoma were examined about the expression of cyclin B1 and cdc2 along with p53 and Ki-67 by immunohistochemical method. The correlation of their expression with various clinicopathologic findings was also analyzed. Cyclin B1 and cdc2 were diffusely expressed in 39 cases (57.4%) and 54 cases (79.4%) out of 68 cases studied, respectively. The mean labeling indices of cyclin B1 and cdc2 in malignant lymphoma were 31.9% and 68.0%, respectively. In normal lymphoid tissues, cyclin B1 and cdc2 were expressed predominantly in the germinal center with mean labeling indices of 13.9% and 28.3%, respectively. The correlation between the expression of cyclin B1 and cdc2 was noted (p=0.013). The expression of Ki-67 was correlated with that of cyclin B1 (p=0.023) and marginally correlated with that of cdc2 (p=0.056). The expression of cdc2 and p53 in complete remission group to chemotherapy was lower than that of progressive disease group (p=0.047, p=0.049). In multivariate analysis, the clinical stage alone showed significance on overall survival (p=0.049). In conclusion, cyclin B1 and cdc2 appeared to be involved in the genesis or progression of malignant lymphoma and cdc2 can be a useful marker for response to chemotherapy.

Determinaçäo dos níveis amigdalianos de miocamicina até 12 horas após a administraçäo / Determination of miocamycin levels up to 12 hours after administration

Foram determinados os níveis amigdalianos de miocamicina em cinco pacientes após administraçäo de dose única de 10mg/kg e em 10 pacientes após dois dias de administraçäo de 10 mg/kg de 8/8 horas. No grupo de doses múltiplas, foram detectados níveis tissulares até 12 horas apús a administraçäo. Neste grupo, os valores observados (Cmax, AUC) foram superiores aos do grupo de dose única, apontando para um acúmulo tecidual do antibiótico com a repetiçäo das doses. Estas observaçöes reforçam a validade de um esquema de administraçäo da miocamicina de 12 em 12 horas

Basófilos de amígdalas palatinas y adenoides en adenoamigdalitis aguda recurrente e hipertrofia adenoamigdalar en niños / Basophils from palatine tonsils and adenoids in recurrent acute adenoid tonsillitis and adenoid tonsillar hypertrophy in children

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