Biomineralized in situ catalytic nanoreactor integrated microneedle patch for on demand immunomodulator supply to combat psoriasis

Abstract

The endogenous immunomodulator adenosine (ADO) was expected to be potentialized as an efficacious mediator to combat psoriasis. However, its efficacy is severely hindered by its poor metabolic stability and insufficient accumulation at the dermatological lesions. Methods: In this study, a biomineralized in situ catalytic nanoreactor was delicately customized by encapsulating ADO precursor (adenosine monophosphate, AMP) within the internal porous skeleton of zeolitic imidazolate framework-90, followed by the biomineralization of the AMP catabolic enzyme on the outer layer. The nanocrystals were then incorporated into a dissolving microneedles patch, which was designed to deliver drugs with precision into the cutaneous lesion and enhance the efficacy of psoriasis treatment. Results: Upon penetration into the skin, the nanoreactors were released and underwent a gradual collapse of their structure, releasing AMP when exposed to the acidic microenvironment. Meanwhile, the acidic pH could trigger an in situ catalytic reaction to continuously produce ADO. This system yielded remarkable results in a psoriasis-like mouse model. The mechanism study demonstrated that this system could substantially reshape the inflammatory ecosystem by inhibiting the keratinocyte hyperplasia, reducing inflammatory cytokine expression, and regulating the infiltration of immune cells. Conclusion: The in situ catalytic nanoreactor integrated microneedle patch is a promising modular platform for co-delivery of prodrugs and their catabolic enzymes, offering a potential solution for various diseases.

Keywords: adenosine; immunoregulation; in situ catalytic nanoreactor; microneedles; psoriasis.

Scheme 1

Schematic diagram of AMP@ZIF-90/ACP integrated microneedle patch for on-demand ADO supply to combat psoriasis.

Figure 1

Synthesis and characterization of AMP@ZIF-90/ACP. (A) Schematic illustration of preparation procedures. (B) Digital photograph of the three products. (C) SEM image of ZIF-90. Scale bar: 4 μm. (D) Zeta potential of ZIF-90, AMP@ZIF-90, and AMP@ZIF-90/ACP. (E) UV-Vis absorption spectra of various samples. (F) pXRD spectra of the raw materials and synthetic products. (G) Schematic diagram of pH-responsive degradation and reaction of AMP@ZIF-90/ACP in the acidic medium. (H) TEM image of ZIF-90 and (I) AMP@ZIF-90/ACP after immersion in PBS (pH 5.5) for 48 h. Scale bar: 200 nm. (J) The ADO concentration and (K) corresponding chromatograms after immersing AMP@ZIF-90/ACP at different pH conditions. (L) The variations of time-dependent AMP and ADO concentrations, and (M) corresponding chromatogramsafter immersing AMP@ZIF-90/ACP in PBS (pH 5.5).

Figure 2

Fabrication and characterization of AMP@ZIF-90/ACP@MNs. (A) Schematic diagram of preparation procedures. (B) Digital photograph, (C) Electron microscope image, and (D) SEM image of AMP@ZIF-90/ACP@MNs. (E) 2D CLSM micrograph and (F) 3D reconstruction image of C6@ZIF-90@MNs. (G) H&E staining section of inserted mice dorsal skin. (H) CLSM tomography of C6 across the mice skin after MNs administration. (I) The dissolution behavior of AMP@ZIF-90/ACP@MN. (J) Fluorescent images of psoriasis-like model mice after administration of C6@ZIF-90@MNs and subcutaneous injection of C6@ZIF-90. (K) Fluorescent image of major organs 24 h post-administration. (L) Total fluorescent intensity of psoriasis-like model mice at different time intervals after administration of C6@ZIF-90@MNs and subcutaneous injection of C6@ZIF-90 (n = 3). All scale bars: 200 μm.

Figure 3

Evaluation of the anti-psoriasis effect. (A) Schematic diagram of experimental schedule. (B) Representative photographs of mice dorsal skin after different treatments. (C) Heatmap of total PASI score of various groups. (D) PASI evaluation of desquamation, erythema, keratoplasia, and total score of different groups during the treatment period (mean± S.D, n = 4). (E) The corresponding H&E staining section of psoriasis-like skin lesions after various treatments. All scale bars: 100 μm. (* P < 0.05, ** P < 0.01, *** P < 0.001, **** P < 0.0001 versus the control group.

Figure 4

Evaluation of the immunosuppressive mechanism. (A) Schematic diagram of the immunosuppressive mechanism of ADO. (B) Representative flow cytometry charts of mice lymph nodes. Quantification of T cells in (C) dorsal skin lesion and (D) lymph nodes after various treatments. Quantification of mature DCs in (E) dorsal skin lesion and (F) lymph nodes after various treatments. Quantification of Treg cells in (G) dorsal skin lesion and (H) lymph nodes after various treatments. (I) Immunofluorescence staining of CD3 and CD68 in dorsal skin lesion sections of control group and AMP@ZIF-90/ACP@MNs group. (mean ± S.D, n = 3). All scale bar: 50 μm. (*P < 0.05, **P < 0.01, ***P < 0.001, ****P < 0.0001 versus the control group.

Figure 5

In vivo systemic inflammatory response and immunofluorescence staining. (A) Relative expression level of cytokines (TNF-α, IL-6, IL-17A, and IL-23) in the serum after different treatments. Concentrations of (B) white blood cells (WBC), (C) monocytes, (D) neutrophil/lymphocyte ratio (NLR), and (E) platelet/lymphocyte ratio (PLR) in the blood biomarker analysis of the control group and AMP@ZIF-90/ACP@MNs group. (F) Immunofluorescence staining of Ki67, IL-6, IL-17A, and IL-22 in mice dorsal skin lesion of control group and AMP@ZIF-90/ACP@MNs group. (mean ± S.D, n = 4). All scale bar: 50 μm. *P < 0.05, **P < 0.01, *** P< 0.001, ****P < 0.0001, ns notes not significant versus the control group.