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Intralymphatic Immunotherapy and Vaccination in Mice
Published on: February 2, 2014
Cellular and morphological changes in lymphoid organs after a single injection of interleukin 1 alpha in the mouse
A Marusić1, I Djikić, M Marusić
1Department of Anatomy Zagreb University School of Medicine, Yugoslavia.
Insights
Recombinant human interleukin-1 alpha (IL-1 alpha) causes rapid changes in mouse immune organs. This inflammatory response involves increased white blood cells and decreased spleen and thymus cellularity.
Area of Science:
- Immunology
- Cellular Biology
- Inflammation Research
Background:
- Interleukin-1 alpha (IL-1 alpha) is a key cytokine in immune responses.
- Understanding IL-1 alpha's systemic effects is crucial for inflammatory disease research.
Purpose of the Study:
- To investigate the effects of recombinant human IL-1 alpha on lymphoid organ morphology and cellularity in mice.
- To correlate peripheral blood changes with lymphoid organ alterations following IL-1 alpha administration.
Main Methods:
- Single intravenous injection of recombinant human IL-1 alpha (100 U) in normal mice.
- Monitoring of peripheral blood cell counts (neutrophils, mononuclears, lymphocytes).
- Assessment of spleen, bone marrow, and thymus cellularity and morphology at various time points.
Main Results:
- Maximal neutrophilia and leukocytosis observed within 1 hour post-injection.
- Significant decrease in spleen cellularity and white pulp volume, with red pulp expansion.
- Thymus exhibited cell depletion and cortical atrophy, peaking at 6 hours.
- Bone marrow cellularity increased transiently at 1 hour, returning to baseline by 6 hours.
Conclusions:
- Single IL-1 alpha injection induces rapid leukocytosis accompanied by spleen and thymus cell depletion.
- Observed morphological and cellular changes suggest immune cell mobilization during inflammation.
- IL-1 alpha plays a significant role in orchestrating acute inflammatory responses and immune cell trafficking.
Abstract:
We investigated the effects of a single i.v. injection of recombinant human interleukin 1 alpha (IL-1 alpha) on the morphology and the cellularity of several lymphoid organs in normal mice. The injection of 100 U of IL-1 alpha resulted in maximal neutrophilia and leukocytosis at 1 h. By 72 h, the numbers of mononuclears, but not that of polymorphonuclears, returned to baseline levels. Absolute increase in mononuclears was paralleled by relative lymphopenia. Changes in the peripheral blood coincided with rapid decrease in the spleen cellularity and white pulp volume (especially the marginal zone), and an increase in the red pulp volume. Bone marrow cellularity was increased at 1 h, but returned to control levels by 6 h after IL-1 injection. Thymus cell depletion and cortex atrophy were maximal at 6 h and could be observed throughout the experiment. These findings indicate that leukocytosis induced by a single i.v. injection of IL-1 alpha in normal mice is concomitant with a rapid cell depletion of the spleen and thymus. Morphological and cellular changes in lymphoid organs may represent the mobilization of immunocompetent cells during the development of the inflammatory response.
