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Gene & Protein in Disease lncRNAs in trained immunity

Figure 3. Schematic diagram illustrating the probable mechanisms of trained immunity modulation
Abbreviation: TCA: Tricarboxylic acid.

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Guo et al. recently demonstrated that the lncRNA RP5‑ It plays a crucial role in the process of X-chromosome
998N21.4 plays a role in promoting immune defense in the inactivation. Moreover, several other lncRNAs are
context of schizophrenia. The researchers found that RP5‑ implicated in the regulation of DNA methylation status in
998N21.4 upregulates the expression of interferon-induced human cells. They can either recruit or inhibit the action
protein with tetratricopeptide repeats IFIT2 and IFIT3. of DNA methyltransferases and demethylases, influencing
Furthermore, the authors observed that RP5‑998N21.4 the epigenetic modifications of DNA. This involvement in
positively regulates the transcription of IFIT2 and IFIT3 by the regulation of DNA methylation highlights the diverse
binding to their promoter regions and influencing histone and intricate roles that lncRNAs play in modulating the
modifications. This research sheds light on the involvement epigenetic landscape of the genome. The observation
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of specific lncRNAs in the immune response and their that CD8+ T cells can differentiate into short-lived effector
potential implications in the context of schizophrenia. cells and memory cells, providing sustained protection
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Targeting the epigenetic regulation of myeloid-derived during immune responses to microbial infection, is well-
suppressor cells (MDSCs) in human sepsis is considered established. In the context of this differentiation process,
imperative. Addressing the epigenetic factors associated a study has suggested the potential involvement of the
with MDSCs in the context of sepsis could potentially lncRNA MALAT1. This lncRNA may play a role in the
contribute to resolving post-sepsis immunosuppression regulation of CD8+ T cell differentiation by mediating
and improving sepsis survival. By modulating the epigenetic repression in response to acute infection.
epigenetic landscape of MDSCs, there is potential for The study implies that MALAT1 could contribute to the
interventions that could enhance the immune response and epigenetic control of CD8+ T cell fate during immune
mitigate the adverse effects of sepsis, leading to improved responses. The regulation of histone modifications plays
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outcomes for individuals affected by this condition. These a crucial role in the establishment of epigenetic memory
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studies highlight the importance of lncRNAs as epigenetic in the context of trained immunity. Specifically, lysine 27
functions. Thus, further understanding the molecular of histone 3 (H3K27) and lysine 4 of histone 3 (H3K4) at
mechanisms behind trained immunity would help explore the promoters of trained immune genes undergo rapid
the lncRNAs as epigenetic targets for therapeutic purposes. acetylation and trimethylation, respectively, during the
The XIST is indeed one of the most extensively studied initial phase of training. Interestingly, upon the removal of
lncRNAs and represents a prime example of a lncRNA the training stimulus, it has been observed that H3K4me3
directly involved in the formation of repressive chromatin. occupancy remains accumulated on the chromatin, while

Volume 3 Issue 2 (2024) 8 doi: 10.36922/gpd.2791