PredGCN: a Pruning-enabled Gene-Cell Net for automatic cell annotation of single cell transcriptome data

Abstract Motivation The annotation of cell types from single-cell transcriptomics is essential for understanding the biological identity and functionality of cellular populations. Although manual annotation remains the gold standard, the advent of automatic pipelines has become crucial for scalable, unbiased, and cost-effective annotations. Nonetheless, the effectiveness of these automatic methods, particularly those employing deep learning, significantly depends on the architecture of the classifier and the quality and diversity of the training datasets. Results To address these limitations, we present a Pruning-enabled Gene-Cell Net (PredGCN) incorporating a Coupled Gene-Cell Net (CGCN) to enable representation learning and information storage. PredGCN integrates a Gene Splicing Net (GSN) and a Cell Stratification Net (CSN), employing a pruning operation (PrO) to dynamically tackle the complexity of heterogeneous cell identification. Among them, GSN leverages multiple statistical and hypothesis-driven feature extraction methods to selectively assemble genes with specificity for scRNA-seq data while CSN unifies elements based on diverse region demarcation principles, exploiting the representations from GSN and precise identification from different regional homogeneity perspectives. Furthermore, we develop a multi-objective Pareto pruning operation (Pareto PrO) to expand the dynamic capabilities of CGCN, optimizing the sub-network structure for accurate cell type annotation. Multiple comparison experiments on real scRNA-seq datasets from various species have demonstrated that PredGCN surpasses existing state-of-the-art methods, including its scalability to cross-species datasets. Moreover, PredGCN can uncover unknown cell types and provide functional genomic analysis by quantifying the influence of genes on cell clusters, bringing new insights into cell type identification and characterizing scRNA-seq data from different perspectives. Availability and implementation The source code is available at https://github.com/IrisQi7/PredGCN and test data is available at https://figshare.com/articles/dataset/PredGCN/25251163.

2 Section 2: Results for 3.4 3 Section 3: Misclassification of Acinar Cells in PredGCN In Fig. 3b, we observe that acinar cells in the mBaron hBaron dataset are predicted as ductal cells.This misclassification occurs because acinar cells are absent in the mBaron dataset, which serves as the reference dataset.Consequently, the model trained on the mBaron dataset lacks data on acinar cells, resulting in an inability to establish effective classification criteria and features for these cells, leading to limitations and inaccuracies in their identification.The primary reason acinar cells are often misidentified as ductal cells is due to their close relationship within the exocrine pancreas.Acinar and ductal cells are closely related in both location and function (Zhou and Melton, 2018).As indicated in Figure S7, the correlation between acinar and ductal cells is more pronounced than with other cell types.Therefore, when the model lacks information on acinar cells, it may misidentify these cells in the hBaron dataset as ductal cells.
We acknowledge that PredGCN currently has some limitations.PredGCN relies on a reference dataset for cell annotation, necessitating high quality and comprehensiveness of the reference data.If the reference dataset is incomplete or contains biases, the annotation results can be significantly impacted.This limitation affects the generalization ability of PredGCN, particularly when encountering new cell types or states.
To address these challenges, we recommend using a more comprehensive reference dataset when employing PredGCN.Avoiding the use of subset datasets for training will help improve the accuracy and generalization capability of the model, ensuring more reliable cell type identification across diverse datasets.
Figure S7: Correlations between cell types in the hBaron dataset.Acinar cells correlate more highly with ductal cells than with other cell types.
6 Section 6: Robustness and Adaptability of PredGCN Thresholds in Identifying Cell Types Across Diverse Datasets To evaluate the robustness of our threshold settings, we conducted validation experiments on various datasets derived from human Peripheral Blood Mononuclear Cells (PBMC) (Ding et al., 2019).Figure S13 illustrates the precision of PredGCN in identifying cell types across different thresholds applied to these datasets.The thresholds tested were 0, 0.4, 0.6, 0.65, 0.7, 0.8, and 1.As shown in Figure S13(a), while a threshold of 0.65 was not the top performer across all datasets, it consistently ranked among the top three in multiple datasets.In contrast, thresholds such as 1.0 achieved higher precision in specific datasets but lacked consistent performance overall.The 0.65 threshold demonstrated balanced perfor-mance, maintaining high precision under various data conditions.Figure S13(b) highlights that the median precision is highest and the data distribution is more concentrated at a threshold of 0.65, indicating stable performance of PredGCN at this threshold.This stability is crucial for identifying unknown cell types in both human pancreas datasets and human PBMC datasets.However, it is important to note that the optimal threshold may vary depending on the dataset, and slight adjustments might be necessary to achieve the best results in different contexts.Future work will involve extending threshold validation to a wider range of datasets, including those from different species and experimental conditions.Additionally, we are exploring adaptive mechanisms to dynamically optimize thresholds based on the specific characteristics of each dataset, aiming to enhance the adaptability and precision of PredGCN.
unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown    (Szklarczyk et al., 2023).In the network, the confidence value was set to 0.7 and the disconnected nodes were hidden.Then, the processed PPI network was put into Cytoscape (v.3.10.1) to display visually the node-to-node connections.Accordingly, Maximal Clique Centrality of cytoHubba (https://apps.cytoscape.org/apps/cytohubba) in the Cytoscape APP Store was applied to recognize the top 10 hub genes from the PPI network.
8 Section 8: Details about gene filtering sub-nets The Bartlett's test can distinguish between differentially variant genes by homogeneity tests.The Bartlett's test is implemented using the R function bartlett.test.The detailed representations of Equation(1) are as follows: where s 2 i is the variance of the feature i.
The KS test is implemented using the R function ks.test and the genes are then ranked and selected based on the p-value of the result.
For the chi-square test, genes with differential proportions are generated using the R function chisq.test(Ma et al., 2020).The genes are then ranked and selected based on the p-value of the result.For Bimodality Index, the genes are also ranked based on the T .The detailed representations of Equation( 5) are as follows: 12 Section 12: Summary of Datasets       As an alternative provision, we also avail a search feature at http://www.aibio-lab.com/PredGCN/index/, as demonstrated in Figure S27(a).Following the task's completion, results can be directly retrieved by utilizing the provided Task ID, as illustrated in Figure S27(b).When the task is completed, users can engage the 'DOWNLOAD" button to acquire the results.

Figure S13 :
Figure S13: The performance of threshold 0.65 on PBMC datasets.(a) Comparison of the precision of PredGCN when the threshold is 0.65 and when there is no threshold.(b) The box plot shows the distribution of PredGCN precision at different thresholds (0, 0.4, 0.6, 0.65, 0.7, 0.8, and 1).

Figure S14 :
Figure S14: Pie chart of the proportion of each cell type in the results identified using PredGCN in the SLE pbmc dataset.

Figure S15 :
Figure S15: Visualization of expression distribution of the top marker gene of each cell type.

Figure S20 :
Figure S20: The (a) Home page and (b) graphical abstract of PredGCN webserver.

Figure S21 :
Figure S21: Two ways to use PredGCN webserver, and two access methods to the usages.

Figure S22 :
Figure S22: Usages of PredGCN webserver under the USE SAMPLE DATASETS tab.

Figure S23 :
Figure S23: Usages of PredGCN webserver under the UPLOAD YOUR OWN DATASETS tab.

Figure S25 :
Figure S25: The interface after the task is submitted.

Figure S26 :
Figure S26: The interface after the task is submitted.

Figure S27 :
Figure S27: Search task with Task ID.
Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet Platelet