Host cell targeting of novel antimycobacterial 4-aminosalicylic acid derivatives with tuftsin carrier peptides.

Mycobacterium tuberculosis is an intracellular pathogen and the uptake of the antimycobacterial compounds by host cells is limited. Novel antimycobacterials effective against intracellular bacteria are needed. New N-substituted derivatives of 4-aminosalicylic acid have been designed and evaluated. To achieve intracellular efficacy and selectivity, these compounds were conjugated to tuftsin peptides via oxime or amide bonds. These delivery peptides can target tuftsin- and neuropilin receptor-bearing cells, such as macrophages and various other cells of lung origin. We have demonstrated that the in vitro antimycobacterial activity of the 4-aminosalicylic derivatives against M. tuberculosis H37Rv was preserved in the peptide conjugates. The free drugs were ineffective on infected cells, but the conjugates were active against the intracellular bacteria and have the selectivity on various types of host cells. The intracellular distribution of the carrier peptides was assessed, and the peptides internalize and display mainly in the cytosol in a concentration-dependent manner. The penetration ability of the most promising carrier peptide OT5 was evaluated using Transwell-inserts and spheroids. The pentapeptide exhibited time- and concentration-dependent penetration across the non-contact monolayers. Also, the pentapeptide has a fair penetration rate towards the center of spheroids formed of EBC-1 cells.

A strong CD8+ T cell-stimulating supramolecular hydrogel.

The development of molecules with immune stimulatory properties is crucial for cancer immunotherapy. In this work, we combined two peptide-based molecules, tuftsin (TKPR) and Nap-GDFDFDY, to develop a novel self-assembling molecule Nap-GDFDFDYTKPR (Comp.3), which has strong CD8+ T cell stimulatory properties. Comp.3 could self-assemble into nanofibers and hydrogels, which significantly improved the stability of tuftsin against enzyme digestion. The nanofibers of Comp.3 enhanced the phagocytic activity of macrophages, promoted the maturation of DCs, and stimulated the expression of cytokines. In addition, it demonstrated an excellent anti-tumor efficacy in vivo by eliciting a strong CD8+ T immune response. Taken together, our observations revealed a powerful immune stimulating nanomaterial that is a promising compound for cancer immunotherapy.

Selank, Peptide Analogue of Tuftsin, Protects Against Ethanol-Induced Memory Impairment by Regulating of BDNF Content in the Hippocampus and Prefrontal Cortex in Rats.

The effects of a peptide anxiolytic Selank synthesized on the basis of the endogenous peptide tuftsin on memory impairment and content of brain-derived neurotrophic factor (BDNF) in brain structures were analyzed in outbred rats receiving 10% ethanol as the only source of fluid for 30 weeks. In the object recognition test, Selank (0.3 mg/kg a day, 7 days, intraperitoneally) produced a cognitive-stimulating effect in 9 months rats not exposed to ethanol (p<0.05) and prevented the formation of ethanol-induced memory and attention disturbances (p<0.01) developing during alcohol withdrawal. In ex vivo experiments, Selank prevented ethanol-induced increase in BDNF content in the hippocampus and frontal cortex (p<0.05). These results indicate positive effects of the tuftsin analogue on age-related memory disturbances associated with chronic alcohol intoxication and confirm the involvement of the neurotrophin mechanism related to BDNF production into the effect of Selank.

Overcharging Effect in Electrospray Ionization Mass Spectra of Daunomycin-Tuftsin Bioconjugates.

Peptide-based small molecule drug conjugates for targeted tumor therapy are currently in the focus of intensive research. Anthracyclines, like daunomycin, are commonly used anticancer drug molecules and are also often applied in peptide-drug conjugates. However, lability of the O-glycosidic bond during electrospray ionization mass spectrometric analysis hinders the analytical characterization of the constructs. "Overprotonation" can occur if daunomycin is linked to positively charged peptide carriers, like tuftsin derivatives. In these molecules, the high number of positive charges enhances the in-source fragmentation significantly, leading to complex mass spectra composed of mainly fragment ions. Therefore, we investigated different novel tuftsin-daunomycin conjugates to find an appropriate condition for mass spectrometric detection. Our results showed that shifting the charge states to lower charges helped to keep ions intact. In this way, a clear spectrum could be obtained containing intact protonated molecules only. Shifting of the protonation states to lower charges could be achieved with the use of appropriate neutral volatile buffers and with tuning the ion source parameters.

Functionalized rifampicin-loaded nanostructured lipid carriers enhance macrophages uptake and antimycobacterial activity.

Tuberculosis is an infectious bacterial disease that causes millions of deaths worldwide. Current treatment recommended by WHO is effective, however it is an extensive and arduous process associated to severe adverse effects, which induces a low patient compliance and the emerging of multidrug resistant tuberculosis. Thus, as a main goal of this study, rifampicin nanoparticles were surface functionalized with a tuftsin-modifed peptide to selectively recognize receptors located on infected alveolar macrophages, enhancing nanoparticles uptake by these cells and improving antimycobacterial activity. A tuftsin-based modified peptide was synthesized and successfully attached to nanoparticles interface (NP-pRIF). In parallel, nanoparticles without peptide were also developed for comparison (NP-RIF). Physicochemical characterization demonstrated that stable and monodisperse nanodelivery systems were obtained, with a controlled drug release profile and non-cytotoxic potential. Moreover, nanoparticles containing peptide were significantly more internalized by macrophages than nanoparticles without peptide over a wide range of time. Both nanoparticles were 2-fold more effective against M. tuberculosis than free rifampicin, suggesting NP-pRIF as a promising strategy for the management of tuberculosis treatment.

Cloning, large-scale production and characterization of fusion protein (P-TUFT-ALT-2) of Brugian abundant larval transcript-2 with tuftsin in Pichia pastoris.

Lymphatic filariasis is a "disease of poor people" due to a large section of affected people with economic backwardness. Therefore, successful elimination of this disease requires a cost-effective prophylactic agent such as vaccine along with conventional drugs. The Abundant Larval Transcript-2 (BmALT-2) protein of Brugia malayi has been recognized as the most potential vaccine candidate. Tuftsin, a tetra-peptide immunopotentiator has already shown the enhanced immunogenicity of various vaccine antigens in earlier studies. This study deals with the development of tuft-alt-2 fusion construct and a suitable culture condition for its large-scale production in Pichia pastoris. The recombinant P. pastoris/tuft-alt-2 with 9-11 copies of the gene construct exhibited the highest expression level. The molecular weight of P-TUFT-ALT-2 was determined as 28 kDa in SDS-PAGE including 3 kDa due to glycosylation. The dry cell biomass was 57.4 gL-1 in the bioreactor. The P-TUFT-ALT-2 expression was measured as about 35 mg L-1, which was 102% higher than flask culture. The P-TUFT-ALT-2 produced the highest 65,000 IgG peak titer in Balb/c mice. Moreover, P-TUFT-ALT-2 exhibited about 9.46% higher splenocyte proliferation than E. coli expressed E-ALT-2 alone. The enhanced secreted production of P-TUFT-ALT-2 in bioreactor would step up its commercialization as an inexpensive commercial vaccine for human lymphatic filariasis.

Surface Layer Modification of Poly(d,l-lactic- co-glycolic acid) Nanoparticles with Targeting Peptide: A Convenient Synthetic Route for Pluronic F127-Tuftsin Conjugate.

Nanoparticles consisting of biodegradable poly(d,l-lactic- co-glycolic acid) (PLGA) are promising carriers for drug molecules to improve the treatment of tuberculosis. Surface modifiers, such as Pluronic F127, are essential for biocompatibility and for the protection against particle aggregation. This study demonstrates a successful approach to conjugate Pluronic F127 coated PLGA nanoparticles with Tuftsin, which has been reported as a macrophage-targeting peptide. Transformation of Pluronic F127 hydroxyl groups-which have limited reactivity-into aldehyde groups provide a convenient way to bind aminooxy-peptide derivatives in a one-step reaction. We have also investigated that this change has no effect on the physicochemical properties of the nanoparticles. Our data showed that coating nanoparticles with Pluronic-Tuftsin conjugate markedly increased the internalization rate and the intracellular activity of the encapsulated drug candidate against Mycobacterium tuberculosis. By employing this approach, a large variety of peptide targeted PLGA nanoparticles can be designed for drug delivery.

Tuftsin-phosphorylcholine (TPC) equally effective to methylprednisolone in ameliorating lupus nephritis in a mice model.

The role of helminth treatment in autoimmune diseases is growing constantly. Systemic lupus erythematosus (SLE) is a multi-system autoimmune disease with challenging treatment options. Tuftsin-phosphorylcholine (TPC) is a novel helminth-based compound that modulates the host immune network. This study was conducted to evaluate the potential value of TPC in ameliorating lupus nephritis in a murine model and specifically to compare the efficacy of TPC to the existing first-line therapy for SLE: corticosteroids (methylprednisolone). Lupus-prone NZBxW/F1 mice were treated with TPC (5 µg/mouse), methylprednisolone (MP; 5 mg/body weight) or phosphate-buffered saline (PBS) (control) three times per week once glomerulonephritis, defined as proteinuria of grade > 100 mg/dl, was established. Levels of anti-dsDNA autoantibodies were evaluated by enzyme-linked immunosorbent assay (ELISA), splenic cytokines were measured in vitro and the kidney microscopy was analysed following staining. TPC and MP treatments improved lupus nephritis significantly and prolonged survival in NZBxW/F1 mice. TPC-treated mice showed a significantly decreased level of proteinuria (P < 0·001) and anti-dsDNA antibodies (P < 0·001) compared to PBS-treated mice. Moreover, TPC and MP inhibited the production of the proinflammatory cytokines interferon IFN-γ, interleukin IL-1ß and IL-6 (P < 0·001) and enhanced expression of the anti-inflammatory cytokine IL-10 (P < 0·001). Finally, microscopy analysis of the kidneys demonstrated that TPC-treated mice maintained normal structure equally to MP-treated mice. These data indicate that the small molecule named TPC hinders lupus development in genetically lupus-prone mice equally to methylprednisolone in most of the cases. Hence, TCP may be employed as a therapeutic potential for lupus nephritis.

Chemical and biological properties of a supramolecular complex of tuftsin and cucurbit[7]uril.

Cucurbit[7]uril (CB7) is an uncharged and water-soluble macrocyclic host. CB7 binds to doubly protonated tuftsin, which is the tetrapeptide Thr-Lys-Pro-Arg, with moderate affinity (Ka=2.1×103M-1). In this study, the host-guest complexation was confirmed by fluorescence titration. This affinity would allow for easy release of the peptide under physiological conditions. According to density functional theory calculations, the structural binding motif involves hydrogen bonding. The most energetically stable form had the Arg side chain inside the CB7 cavity. The effects of the tuftsin-CB7 complex on the proliferation and cytokine activity of immune cells were studied. The complex had broader spectrum immunomodulation than free peptides, and caused statistically significant (p<0,05) changes in cytokine production (tumor necrosis factor-α, interleukin-2, interferon-γ, and interleukin-10) by mononuclear cells. By contrast, the free peptide only activated tumor necrosis factor-α production.

Synthesis of functionalized new conjugates of batracylin with tuftsin/retro-tuftsin derivatives and their biological evaluation.

New batracylin conjugates with tuftsin/retro-tuftsin derivatives were designed and synthesized using T3P as a coupling agent. The conjugates possess an amide bond formed between the carboxyl group of heterocyclic molecule and the N-termini of the tuftsin/retro-tuftsin chain. The in vitro cytotoxic activity of the new analogues and their precursors was evaluated using a series of human and murine tumor cells. BAT conjugates containing retro-tuftsin with branched side aminoacid chain, in particular with leucine or isoleucine, were about 10-fold more cytotoxic toward two human tumor cell lines (lung adenocarcinoma (A549) and myeloblastic leukemia (HL-60)). These compounds showed about 10-fold increased cytotoxicity against the two types of tumor cells compared to parent BAT. We have not observed important differences in the mechanism of action between BAT and its cytotoxic tuftsin/retro-tuftsin conjugates. We propose that high biological activity of the most active BAT conjugates is a result of their greatly increased intracellular accumulation.

Phosphorylcholine-tuftsin compound prevents development of dextransulfate-sodium-salt induced murine colitis: implications for the treatment of human inflammatory bowel disease.

Improved clinical findings of inflammatory bowel disease (IBD) upon treatment with helminthes and their ova were proven in animal models of IBD and in human clinical studies. The immunomodulatory properties of several helminthes were attributed to the phosphorylcholine (PC) molecule. We assessed the therapeutic potential of tuftsin-PC conjugate (TPC) to attenuate murine colitis. Colitis was induced by Dextransulfate-Sodium-Salt (DSS) in drinking water. TPC was given by daily oral ingestion (50 µg/0.1 ml/mouse or PBS) starting at day -2. Disease activity index (DAI) score was followed daily and histology of the colon was performed by H&E staining. Analysis of the cytokines profile in distal colon lysates was performed by immunoblot. Treatment of DSS induced colitis with TPC prevented the severity of colitis, including a reduction in the DAI score, less shortening of the colon and less inflammatory activity in histology. The immunoblot showed that the colitis preventive activity of TPC was associated with downregulation of colon pro-inflammatory IL-1ß, TNFα and IL-17 cytokines expression, and enhancement of anti-inflammatory IL-10 cytokine expression. In the current study, we demonstrated that TPC treatment can prevent significantly experimental colitis induction in naïve mice. We propose the TPC as a novel potential small synthetic molecule to treat colitis.

Tuftsin-based, EGFR-targeting fusion protein and its enediyne-energized analog show high antitumor efficacy associated with CD47 down-regulation.

Tuftsin (TF) is an immunomodulator tetrapeptide (Thr-Lys-Pro-Arg) that binds to the receptor neuropilin-1 (Nrp1) on the surface of cells. Many reports have described anti-tumor activity of tuftsin to relate with nonspecific activation of the host immune system. Lidamycin (LDM) that displays extremely potent cytotoxicity to cancer cells is composed of an apoprotein (LDP) and an enediyne chromophore (AE). In addition, Ec is an EGFR-targeting oligopeptide. In the present study, LDP was used as protein scaffold and the specific carrier for the highly potent AE. Genetically engineered fusion proteins LDP-TF and Ec-LDP-TF were prepared; then, the enediyne-energized fusion protein Ec-LDM-TF was generated by integration of AE into Ec-LDP-TF. The tuftsin-based fusion proteins LDP-TF and Ec-LDP-TF significantly enhanced the phagocytotic activity of macrophages as compared with LDP (P < 0.05). Ec-LDP-TF effectively bound to tumor cells and macrophages; furthermore, it markedly suppressed the growth of human epidermoid carcinoma A431 xenograft in athymic mice by 84.2 % (P < 0.05) with up-regulated expression of TNF-α and IFN-γ. Ec-LDM-TF further augmented the therapeutic efficacy, inhibiting the growth of A431 xenograft by 90.9 % (P < 0.05); notably, the Ec-LDM-TF caused marked down-regulation of CD47 in A431 cells. Moreover, the best therapeutic effect was recorded in the group of animals treated with the combination of Ec-LDP-TF with Ec-LDM-TF. The results suggest that tuftsin-based, enediyne-energized, and EGFR-targeting fusion proteins exert highly antitumor efficacy with CD47 modulation. Tuftsin-based fusion proteins are potentially useful for treatment of EGFR- and CD47-overexpressing cancers.

Anticancer activity of tuftsin-derived T peptide in postoperative residual tumors.

Immune adjuvants have been used in cancer biotherapies to stimulate immune response to tumor cells. Despite their potential as anticancer reagents, there are several impediments to their use in clinical applications. In this study, we aim to modify the existing tuftsin structure and evaluate its antitumor activity in preclinical models. We synthesized a novel tuftsin derivative, namely, the T peptide (TP), by linking four tuftsin peptides, which showed enhanced stability in vivo. We then evaluated its anticancer activity in a postoperative residual tumor model in mice, where we surgically removed most of the primary tumor from the host, a procedure mimicking clinically postoperative patients. Despite the limited effect in intact solid tumors, TP strongly inhibited relapsed growth of residual tumors in postsurgical mice. Surgical resection of tumors accelerated residual tumor growth, but TP slowed down this process significantly. Interestingly, TP showed similar effects in human xenograft residual models. As an immunomodulator, TP could synergize the functions of macrophages, thus inhibiting the growth of cocultured tumor cells in vitro. Furthermore, TP could shift the macrophages to the tumor-suppressive M1 type and mobilize them to produce elevated cytotoxic TNF-α and NO. As a result, TP effectively prolonged the survival time of tumor-resected mice. Using the postoperative residual tumor models, we provide a body of evidence showing the antitumor activity of TP, which causes no obvious toxicity. Our study highlights the potential of TP as a postoperative adjuvant in cancer therapies.

The second life of antibodies.

Antibodies (immunoglobulins, Ig) are used by the immune system to identify and neutralize foreign objects and are responsible for antigen-binding and effector functions. Immunoglobulin G (IgG) is the major serum immunoglobulin of a healthy human (~75% of the total Ig fraction). The discovery in 1970 of the endogenous tetrapeptide tuftsin (Thr-Lys-Pro-Arg, fragment 289-292 of the C(H2)-domain of the heavy (H) chain of IgG), possessing both immunostimulatory and neurotrophic activities, was an impetus for the search for new biologically active peptides of immunoglobulin origin. As a result, fragments of the H-chain of IgG produced as a result of enzymatic cleavage of IgG within the antigen-antibody complex were discovered, synthesized, and studied. These fragments include rigin (341-344), immunorphin (364-373), immunocortin (11-20), and peptide p24 (335-358) and its fragments. In this review the properties of these peptides and their role in regulating the immune response are analyzed.

New conjugates of tuftsin and muramyl dipeptide as stimulators of human monocyte-derived dendritic cells.

Muramyl dipeptide (MDP) and tuftsin are known biologically active compound displaying a significant influence on various cell populations of innate immune response. MDP, as a fragment of bacterial cell wall, stimulates not only macrophages and monocytes, but also dendritic cells. In contrast, little is known about tuftsin influence on these cells. Therefore it seemed vital to access whether tuftsin or its derivatives conjugated with MDP could influence the activity of this subpopulation of antigen presenting cells (APC). Immature dendritic cells (iDCs) were derived from human monocytes through eight-day tissue culture supplemented with hrIL-4 and hrGM-CSF. On the day 9 DCs were stimulated with newly synthesized conjugates of tuftsin and muramyl dipeptide. The influence of the examined compounds on the activity and maturity of monocyte-derived DCs was estimated by flow cytometry analysis. The flow cytometry analysis revealed that tuftsin and some of its analogues do stimulate maturation and activity of DCs but to a lesser extend in comparison to MDP. The obtained results suggest further development of the experiments concerning the influence of MDP and tuftsin analogues on the activity of dendritic cells.

Enhanced immune response induced by a potential influenza A vaccine based on branched M2e polypeptides linked to tuftsin.

Vaccination is the most effective means for preventing influenza-associated morbidity and mortality. Since the influenza virus mutates frequently, the virus strains for new vaccine production should be changed according to predicted epidemic strains. The extracellular domain of matrix protein 2 (M2e) is 24 amino acids long, which is highly conserved and therefore a good target for the development of a universal vaccine which may protect against a much wider range of influenza A virus strains. However its low antigenicity and immunogenicity, which are related to its small size, poses a big challenge for vaccine development. Multiple antigen peptide system (MAP) is based on an inert core molecule of radially branching lysine dendrites onto which a number of peptide antigens are anchored. Tuftsin is an immuno-stimulant molecule peptide. Here we developed a novel peptide vaccine by connecting a tuftsin to a branched, four-copy M2e. Not only did this increase the molecular mass, but also potentiate the immunogenicity. Two branched peptides, (M2e)4-tuftsin and (M2e)4-G4(tuftsin was replaced with four glycines), and a M2e monomer were synthesized using standard solid-phase methods. In vitro and in vivo studies were performed to compare their antigenicity and immunogenicity. Experiments in BALB/c mice demonstrated that the branched M2e could induce stronger humoral and cellular immune responses than the M2e monomer, and (M2e)4-tuftsin induced stronger humoral and cellular immune response than (M2e)4-G4. After lethal challenge with influenza virus PR8 strain, up to 80% of the animals in the (M2e)4-tuftsin vaccinated group still survived, in contrast to 44% in the (M2e)4-G4 group and 30% in the M2e monomer group. The combination of branched polypeptides and tuftsin in vaccine design is presented here for the first time, and the results show that the new construct is a promising candidate for a universal vaccine against the influenza A virus.

New conjugates of muramyl dipeptide and nor-muramyl dipeptide linked to tuftsin and retro-tuftsin derivatives significantly influence their biological activity.

The synthesis and biological activity of new conjugates of muramyl dipeptide (MDP) and nor-muramyl dipeptide (nor-MDP) with tuftsin and retro-tuftsin derivatives containing isopeptide bond between ε-amino group of lysine and carboxyl group of simple amino acids such as Ala, Gly and Val are presented. We presumed, based on the cytokine profile, that the examined conjugates of tuftsin and MDP were capable of activating antibacterial mechanisms by switching on Th1 immune response. The most active were compounds 11, 14 and 19-23.

Augmentation of antileishmanial efficacy of miltefosine in combination with tuftsin against experimental visceral leishmaniasis.

Current drugs for the treatment of visceral leishmaniasis are inadequate, and their efficacies are also compromised due to suppression of immune function during the course of infection. Miltefosine is the only promising orally active antileishmanial drug, but due to its long half-life, there is risk of development of resistance. To overcome these problems, efforts are needed to develop combination therapy of miltefosine with effective immunostimulating agents where a decrease of parasitic burden and simultaneous enhancement of adaptive immunity can be achieved. In the present study, we have explored the antileishmanial efficacy of a subcurative dose of miltefosine in combination with free as well as liposomal palmitoyl tuftsin (p-tuftsin) using a Leishmania donovani/BALB/c mouse model. When miltefosine (2.5 mg/kg for 5 days) was given with free p-tuftsin, the inhibitory effect was significantly increased from 49.6% to 66% (P < 0.01), which was further enhanced up to 81% (P < 0.001) when given after liposomal encapsulation of p-tuftsin. Significant enhancement in parasitic inhibition (93%, P < 0.01) was witnessed when animals were co-administered with liposomal p-tuftsin + 5 mg/kg × 5 days dose of miltefosine (72.1%). Enhancement in the production of Th1 cytokines (IL-12, TNF-α, and IFN-γ), reactive oxygen, and nitrogen metabolites was witnessed in the combination group. A remarkable increase in phagocytosis index was also observed indicating overall immunological enhancement to antileishmanial activity of miltefosine by p-tuftsin.

Depolymerized chitosans functionalized with bPEI as carriers of nucleic acids and tuftsin-tethered conjugate for macrophage targeting.

Development of efficient and safe nucleic acid carriers (vectors) is one of the essential requirements for the success of gene therapy. Here, we have evaluated the gene transfer capability of chitosan-PEI (CP) conjugates prepared by conjugating low molecular weight branched polyethylenimine (LMWP) with depolymerized chitosans (7 and 10 kDa) via their terminal aldehyde/keto groups. The CP conjugates interacted efficiently with nucleic acids and also showed higher cellular uptake. These conjugates on complexation with DNA yielded nanoparticles in the size range of 100-130 nm (in case of C7P) and 115-160 nm (in case of C10P), which exhibited significantly higher transfection efficiency (~2-42 folds) in vitro compared to chitosans (high and low mol. wt.) and the commercially available transfection reagents retaining cell viability almost comparable to the native chitosan. Of the two CP conjugates, chitosan 7 kDa-LMWP (C7P) displayed higher gene transfer ability in the presence and absence of serum. Luciferase reporter gene analysis in male Balb/c mice receiving intravenous administration of C7P3/DNA polyplex showed the maximum expression in their spleen. Further, tuftsin, a known macrophage targeting molecule, was tethered to C7P3 and the resulting complex, i.e., C7P3-T/DNA, exhibited significantly higher gene expression in cultured mouse peritoneal macrophages as compared to unmodified C7P3/DNA complex without any cytotoxicity demonstrating the suitability of the conjugate for targeted applications. Conclusively, the study demonstrates the potential of the projected conjugates for gene delivery for wider biomedical applications.

Tuftsin-modified alginate nanoparticles as a noncondensing macrophage-targeted DNA delivery system.

The main objective of this study was to evaluate macrophage-targeted alginate nanoparticles as a noncondensing gene delivery system for potential anti-inflammatory therapy. An external gelation method was employed to form plasmid DNA-encapsulated alginate nanoparticles. The nanoparticle surface was modified with a peptide sequence containing tuftsin (TKPR), and transfection efficiency was determined in J774A.1 macrophages. The effect of transfected mIL-10 in blocking expression of tumor necrosis factor-alpha (TNF-α) was evaluated in lipopolysaccharide (LPS)-stimulated cells. Scrambled peptide- and tuftsin-modified cross-linked alginate nanoparticles efficiently encapsulated plasmid DNA and protected against DNase I degradation. The transgene expression efficiencies, measured using GFP and mIL-10 expressing plasmid DNA, were highest with tuftsin-modified nanoparticles. Levels of TNF-α were significantly lower (p < 0.0001) in LPS-stimulated cells that were transfected with mIL-10 using alginate nanoparticles. The results of the study show that noncondensing alginate nanoparticles can efficiently deliver plasmid DNA, leading to sustained in vitro gene expression in macrophages.