Histiocytic sarcoma (HS) is an aggressive hematological malignancy whose trans-formed cells exhibits morphological and immunophenotypic characteristics similar to macrophages, and arise de novo, or as part of a clonal ‘‘evolution’’ of other pre-existing hematological neoplasms. This study investigates the potential use of the J774A.1 cell line (a line derived from murine tumor cells, commonly used in macrophage research) as a research model for the role of polydisperse extracellular vesicles (PEVs) secreted by the HS cells, considering that bacterial infections are common in patients with cancer, including HS. The influences of bacterial components on tumor progression are still not fully understood. We stimulated the J774A.1 cell line in vitro with a fraction of E. coli and our results show that the bacterial stimulation increases the secretion of PEVs by these cells. Comparative results of J774A.1 cells with PEVs using confocal and scanning electron microscopy with micrographic reports of HS histological slides (from several cited mammal species, including humans) suggest a possible relationship of large PEVs with marks, footprints or traces of possible large PEVs disrupted in the HS of these reports. A subsequent proteomic analysis of these PEVs revealed a diverse subcellular origin of its components such as proteins as including: Triosephosphate isomerase (TPI), Heat shock cognate 71 kDa, Apolipoprotein A-1, Rho GDP-dissociation inhibitor 1, GAPDH, Galectin, Moesin, globular Actin and Annexin. These results highlight the importance of studying the interplay between the HS, others hematological cancers, and bacterial infections to better understand progression of this cancer, identify new therapeutic targets and emphasize the importance of preventing bacterial infections in cancer patients. Furthermore, the results demonstrate the potential use of the stimulated J774A.1 cell line for research of the HS-related PEVs.