Assessment of ability of human adipose derived stem cells for long term overexpression of IL-11 and IL-13 as therapeutic cytokines

Preclinical study of engineering MSCs promoting diabetic wound healing and other inflammatory diseases through M2 polarization

BACKGROUND

Diabetic foot ulcer (DFU) represents a common and severe complication of diabetes mellitus. Effective and safe treatments need to be developed. Mesenchymal stem cells (MSCs) have demonstrated crucial roles in tissue regeneration, wound repair and inflammation regulation. However, the function is limited. The safety and efficacy of gene-modified MSCs is unknown. Therefore, this study aimed to investigate whether genetically modified MSCs with highly efficient expression of anti-inflammatory factors promote diabetic wound repair by regulating macrophage phenotype transition. This may provide a new approach to treating diabetic wound healing.

METHODS

In this study, human umbilical cord-derived MSCs (hUMSCs) were genetically modified using recombinant lentiviral vectors to simultaneously overexpress three anti-inflammatory factors, interleukin (IL)-4, IL-10, IL-13 (MSCs-3IL). Cell counting kit-8, flow cytometry and differentiation assay were used to detect the criteria of MSCs. Overexpression efficiency was evaluated using flow cytometry, quantitative real-time PCR, Western blot, enzyme-linked immunosorbent assay, and cell scratch assay. We also assessed MSCs-3IL's ability to modulate Raw264.7 macrophage phenotype using flow cytometry and quantitative real-time PCR. In addition, we evaluated diabetic wound healing through healing rate calculation, HE staining, Masson staining, and immunohistochemical analysis of PCNA, F4/80, CD31, CD86, CD206, IL-4, IL-10 and IL-13. In addition, we evaluated the safety of the MSCs-3IL cells and the effect of the cells on several other models of inflammation.

RESULTS

MSCs-3IL efficiently expressed high levels of IL-4 and IL-10 (mRNA transcription increased by 15,000-fold and 800,000-fold, protein secretion 400 and 200 ng/mL), and IL-13 (mRNA transcription increased by 950,000-fold, protein secretion 6 ng/mL). MSCs-3IL effectively induced phenotypic polarization of pro-inflammatory M1-like macrophages (M1) towards anti-inflammatory M2-like macrophages (M2). The enhancement of function does not change the cell phenotype. The dynamic distribution in vivo was normal and no karyotype variation and tumor risk was observed. In a mouse diabetic wound model, MSCs-3IL promoted diabetic wound healing with a wound closure rate exceeding 96% after 14 days of cell treatment. The healing process was aided by altering macrophage phenotype (reduced CD86 and increased CD206 expression) and accelerating re-epithelialization.

CONCLUSIONS

In summary, our study demonstrates that genetically modified hUMSCs effectively overexpressed three key anti-inflammatory factors (IL-4, IL-10, IL-13). MSCs-3IL-based therapy enhances diabetic wound healing with high efficiency and safety. This suggests that genetically modified hUMSCs could be used as a novel therapeutic approach for DFU repair.

Inhibition of LPCAT3 exacerbates endoplasmic reticulum stress and HBV replication

BACKGROUND

Altered phospholipid metabolism plays a key role in changing the immune microenvironment and severely affecting T-cell function. LPCAT3 is one of the vital enzymes regulating phospholipid metabolism. This study aims to verify the effect of LPCAT3 on HBV replication in vitro and the chronic progression of hepatitis B infection based on the results of lipidomic.

METHODS

Untargeted lipidomic analysis was employed to scrutinize discrepancies in lipid metabolites between 40 HBV-infected patients and those who spontaneously cleared the virus. Subsequently, enzyme-linked immunosorbent assay (ELISA), enzyme-linked immunospot assay (ELISPOT), western blotting (WB) and quantitative polymerase chain reaction (qPCR) were utilized to investigate LPCAT3 expression and assess HBV replication and endoplasmic reticulum stress (ERS).

RESULTS

A comparative analysis between HBV-infected patients and those experiencing spontaneous clearance revealed significant disparities in 24 lipid metabolites. Among these, phosphatidylcholine (PC) and lysophosphatidylcholine (LPC), constituting half (12/24) of the identified metabolites, were identified as substrates and products of LPCAT3. In vitro studies demonstrated that inhibiting LPCAT3 led to elevated expression levels of hepatitis B surface antigen (HBsAg), HBV-DNA, and interferon-γ (IFN-γ) (P < 0.05), indicative of heightened HBV replication. Furthermore, LPCAT3 inhibition significantly upregulated the expression of genes associated with ERS (P < 0.05).

CONCLUSIONS

Inhibiting LPCAT3 significantly correlates with HBV replication and induces inflammation by enhancing ERS. We hypothesize that LPCAT3 serves as a potential biomarker for hepatitis B virus replication and chronic progression. Furthermore, these findings elucidate the malignant progression of HBV infection from the standpoint of lipid metabolism, offering a novel insight for subsequent mechanistic exploration or therapeutic studies.

LAY SUMMARY

LPCAT3 inhibition enhances endoplasmic reticulum stress and HBV replication by altering the membrane phospholipid composition and promotes chronic hepatitis B progression.

Influence of hormones in multiple sclerosis: focus on the most important hormones

Hormonal imbalance may be an important factor in the severity of multiple sclerosis (MS) disease. In this context, hormone therapy has been shown to have immunoregulatory potential in various experimental approaches. There is increasing evidence of potentially beneficial effects of thyroid, melatonin, and sex hormones in MS models. These hormones may ameliorate the neurological impairment through immunoregulatory and neuroprotective effects, as well as by reducing oxidative stress. Expanding our knowledge of hormone therapy may be an effective step toward identifying additional molecular/cellular pathways in MS disease. In this review, we discuss the role of several important hormones in MS pathogenesis in terms of their effects on immunoregulatory aspects and neuroprotection.