The milky spots are structures found in the omentum of humans and other vertebrates, representing a fraction of the lymphomyeloid tissue associated with the celom. They majorly consist of B lymphocytes, T lymphocytes, and macrophages. Also found in smaller quantities are mesothelial, stromal, dendritic, and rare mast cells. In an experimental model of Schistosoma mansoni infection, there is significant activation of the omentum and milky spots, which exhibit numerous eosinophils. Despite being described for many years, the complete profile of cells found in milky spots and their functions remains largely unexplored. Here, we evaluate the leukocyte populations of the milky spots in homeostasis and a murine model of Schistosoma mansoni infection. The histopathological characterizations, phenotypic profile analysis, and characterization of the eosinophilic potential of progenitors and precursors comparing the milky spots with the spleen and bone marrow showed significant activation of milky spots in infected mice, with changes in the profile over the analyzed times, showing signs of migration and activation of eosinophils, with local eosinopoiesis and maintenance of the eosinophilic population. In naive mice, B1a and B1b cells comprise only a small fraction of B lymphocytes. However, B1b cells expand significantly during infection, peaking at 60 DPI before stabilizing by 90 DPI. B1a cells also increase initially but decrease over time. The behavior of milky spots differs from other primary and secondary lymphoid organs, acting as a central lymphoid organ in cavity immunity.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1093/intimm/dxae064 | DOI Listing |
Oncoimmunology
December 2024
Internal Medicine, University of New Mexico Health Science Center, Albuquerque, NM, USA.
Adv Healthc Mater
October 2024
Department of Internal Medicine, University of New Mexico Health Science Center, Albuquerque, NM, 87131, USA.
Intraperitoneal (IP) administration of immunogenic mesoporous silica nanoparticles (iMSN) in a mouse model of metastatic ovarian cancer promotes the development of tumor-specific CD8 T cells and protective immunity. IP delivery of iMSN functionalized with the Toll-like receptor (TLR) agonists polyethyleneimine (PEI), CpG oligonucleotide, and monophosphoryl lipid A (MPLA) stimulated rapid uptake by all peritoneal myeloid subsets. Myeloid cells quickly transported iMSN to milky spots and fat-associated lymphoid clusters (FALCs) present in tumor-burdened adipose tissues, leading to a reduction in suppressive T cells and an increase in activated memory T cells.
View Article and Find Full Text PDFInt Immunol
October 2024
Laboratório de Medicina Experimental e Saúde, Instituto Oswaldo Cruz, Fiocruz, Rio de Janeiro, Brazil.
The milky spots are structures found in the omentum of humans and other vertebrates, representing a fraction of the lymphomyeloid tissue associated with the celom. They majorly consist of B lymphocytes, T lymphocytes, and macrophages. Also found in smaller quantities are mesothelial, stromal, dendritic, and rare mast cells.
View Article and Find Full Text PDFPlant Dis
October 2024
Guangxi University, 100, Daxue RoadNanning, Guangxi, China, 530005;
Ann Anat
October 2024
Poltava State Medical University, Department of Human Anatomy, Shevchenko str. 23, Poltava 36011, Ukraine.
Background: Publications report that all mammals have two omenta, namely, lesser omentum and greater omentum. Basically, these organs, which share the same name except for the adjective "lesser" or "greater," should not differ from each other. However, no clear description of the structure of the lesser omentum, as well as comparative morphological analysis between the lesser and greater omenta have been found in the literature, which necessitates a thorough investigation.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!