Spleen: Reparative Regeneration and Influence on Liver

Abstract

This review considers experimental findings on splenic repair, obtained in two types of small animal (mouse, rat, and rabbit) models: splenic resections and autologous transplantations of splenic tissue. Resection experiments indicate that the spleen is able to regenerate, though not necessarily to the initial volume. The recovery lasts one month and preserves the architecture, albeit with an increase in the relative volume of lymphoid follicles. The renovated tissues, however, exhibit skewed functional profiles; notably, the decreased production of antibodies and the low cytotoxic activity of T cells, consistent with the decline of T-dependent zones and prolonged reduction in T cell numbers. Species–specific differences are evident as well, with the post-repair organ mass deficiency most pronounced in rabbit models. Autotransplantations of splenic material are of particular clinical interest, as the procedure can possibly mitigate the development of post-splenectomy syndrome. Under these conditions, regeneration lasts 1–2 months, depending on the species. The transplants effectively destroy senescent erythrocytes, assist in microbial clearance, and produce antibodies, thus averting sepsis and bacterial pneumonia. Meanwhile, cellular sources of splenic recovery in such models remain obscure, as well as the time required for T and B cell number reconstitution.

A large gastric splenosis mimicking gastrointestinal stromal tumor: A case report and literature review

“…The vascular network and lymphoid tissue of the regenerated spleen tissue undergo adjustments, with undifferentiated reticular cells and fibrous tissue-forming scaffolds. Subsequent differentiation results in the formation of endothelial sinuses, capillaries and lymphocytes, ultimately constituting splenic tissue ( 35 , 36 ). The blood supply is maintained by several small vessels in the surrounding tissues rather than the splenic arteries ( 37 ).…”

The spleen as a possible source of serine protease inhibitors and migrating monocytes required for liver regeneration after 70% resection in mice

“…The products of decay enter systemic circulation and eventually reach the spleen where they stimulate pro-inflammatory ad pro-fibrotic cytokine and growth factor secretion ( Akahoshi et al, 2002 ; Asanoma et al, 2014 ; Tang et al, 2016 ). Straightforward delivery of these factors to the liver via the portal vein closes the loop; splenectomy cancels the feedback altogether ( Elchaninov et al, 2022 ).…”

“…The basis of this interaction is the portal circulation linking the spleen and liver, as well as the presence of common barrier and immune functions ( Tarantino et al, 2013 ; Li et al, 2017 ). Despite the direct connection of the liver and spleen, the specific mechanisms of mutual influence of these organs, including reparative processes, remain poorly understood ( Yamada et al, 2016 ; Liu et al, 2018 ; Elchaninov et al, 2022 ).…”

An Eye on Kupffer Cells: Development, Phenotype and the Macrophage Niche

“…The effect is accompanied by an increase in CD68+ macrophage counts in the lungs [ 131 ]. The coherence between monocyte/macrophage populations of the spleen and the liver is more comprehensible given the anatomical connection between the two organs via portal circulation [ 132 , 133 ]. At the same time, the spleen has been implicated as a monocyte supply for other organs as well.…”