Cyclodextrin metal-organic framework-based protein biocomposites

Abstract

Materials are needed to increase the stability and half-life of therapeutic proteins during delivery. These materials should be biocompatible and biodegradable. Here, we demonstrate that enzymes and immunoproteins can be encapsulated inside cyclodextrin based metal-organic frameworks using potassium as the metal node. The release profile can be controlled with the solubility of the cyclodextrin linker. The activity of the proteins after release is determined using catalytic and in vitro assays. The results show that cyclodextrin metal-organic framework-based protein biocomposites are a promising class of materials to deliver therapeutic proteins.

Fig. 1

Encapsulation Efficiency of BSA, Catalase, Myoglobin, and Interleukin-2 for γ-CD-MOFs (blue) and β-CD-MOFs (brown). Error determined by triplicates

Fig.2

a) PXRD of γ-CD-MOFs and SEM of b) γ-CD-MOFs c) BSA@γ-CD-MOFs d) Catalase@γ-CD-MOFs e) Myoglobin@γ-CD-MOFs f) Interleukin-2@γ-CD-MOFs. Scale bar: 2 μm. g) pellet of protein@γ-CD-MOFs. Scale bar:1 cm

Fig.3

a) PXRD of β-CD-MOFs and SEMs of b) β-CD-MOFs c) BSA@β-CD-MOFs d) Catalase@β-CD-MOF e) Myoglobin@β-CD-MOFs f) Interleukin-2@β-CD-MOFs. Scale bar : 2 μm g) pellet of protein@β-CD-MOFs. Scale Bar: 1 cm.

Fig.4

Release profiles of BSA encapsulated in β-CD-MOFs (blue), γ-/β-CD-MOFs (brown), and γ-CD-MOFs (orange).

Fig.5

Catalytic assay of free Catalase (orange), Catalase encapsulated into β-CD-MOF (brown), Catalase encapsulated into γ-CD-MOF (blue), and no catalase (gray). Stirring at 300 rpm was used in all solutions during the experiment.

Figure 6.

a. CellTrace Violet fluorescence profiles of CD4⁺ T cells either unstimulated or cultured with 200 ng/ml free interleukin-2 (IL-2), 50 ng/ml anti-CD3ε antibodies, or anti-CD3ε + 20 ng/ml free interleukin-2. b. CellTrace Violet profiles of CD4⁺ T cells stimulated with anti-CD3ε + myoglobin or interleukin-2 encapsulated to γ or β-CD-MOF (20 ng/ml). c. Proliferation of CD4⁺ and CD8⁺ T cells after stimulation with anti-CD3ε plus graded doses of encapsulated myoglobin or interleukin 2, or free interleukin 2. Means and SD are shown. For encapsulated interleukin-2, * signifies p<0.05 towards the correspondent encapsulated myoglobin, while # symbolizes p<0.05 against free interleukin-2. Statistical analysis by Student’s t test. One experiment representative of two is shown.

Scheme 1.

Encapsulation of proteins (Catalase/Interleukin-2) and the activity of the related CD-MOF biocomposites, as catalyst for oxygen removal, and as immunomodulator for immune cell proliferation