Microsphere-based composition for preventing and/or reversing new-onset autoimmune diabetes

Abstract

AS-oligonucleotides are delivered in microsphere form in order to induce dendritic cell tolerance, particularly in the non-obese-diabetic (NOD) mouse model. The microspheres incorporate antisense (AS) oligonucleotides. A process includes using an antisense approach to reverse an autoimmune diabetes condition in NOD mice in vivo. The oligonucleotides are targeted to bind to primary transcripts CD40, CD80, CD86 and their combinations.

Description

BACKGROUND

The present disclosure generally relates to an antisense approach to prevent and/or reverse an autoimmune diabetes condition in NOD mice. This includes microsphere delivery of AS-oligonucleotides by injection to achieve therapeutic effect that causes a negative modulating activity, particularly in the non-obese-diabetic (NOD) mouse model. The microspheres are fabricated using totally aqueous conditions, which microspheres incorporate one or more antisense (AS) oligonucleotides.

Microparticles, microspheres, and microcapsules are solid or semi-solid particles having a diameter of less than one millimeter, and may be less than 100 microns, which can be formed of a variety of materials, including synthetic polymers, proteins, and polysaccharides. Microspheres have been used in many different applications, primarily separations, diagnostics, and drug delivery.

A number of different techniques can be used to make these particles from synthetic polymers, natural polymers, proteins and polysaccharides, including phase separation, solvent evaporation, emulsification, and spray drying. Generally the polymers form the supporting structure of these microspheres, and the drug of interest is incorporated into the polymer structure. Exemplary polymers used for the formation of microspheres include homopolymers and copolymers of lactic acid and glycolic acid (PLGA) as described in U.S. Pat. No. 5,213,812 to Ruiz, U.S. Pat. No. 5,417,986 to Reid et al., U.S. Pat. No. 4,530,840 to Tice et al., U.S. Pat. No. 4,897,268 to Tice et al., U.S. Pat. No. 5,075,109 to Tice et al., U.S. Pat. No. 5,102,872 to Singh et al., U.S. Pat. No. 5,384,133 to Boyes et al., U.S. Pat. No. 5,360,610 to Tice et al., and European Patent Application Publication Number 248,531 to Southern Research Institute; block copolymers such as such as Tetronic®908 and poloxamer 407 as described in U.S. Pat. No. 4,904,479 to Illum; and polyphosphazenes as described in U.S. Pat. No. 5,149,543 to Cohen et al. Microspheres produced using polymers such as these exhibit a poor loading efficiency and are often only able to incorporate a small percentage of the drug of interest into the polymer structure. Therefore, substantial quantities of these types of microspheres often must be administered to achieve a therapeutic effect. In addition, these polymers typically are hydrophobic, negatively impacting the dissolution of the drug of interest. Polymers typically used in this context include polylactic glycolic acid (PLGA).

An objective for the medical community is the delivery of nucleic acids to the cells in an animal for treatment of various diseases including diabetes. In many approaches, nucleic acids can be delivered to cells in culture (in vitro) relatively efficiently with the addition of transfection agents. In addition, in vivo, the presence of endogenous nucleases results in a high rate of nucleic acid degradation when nucleic acid is delivered to animals.

In addition to protecting nucleic acid from nuclease digestion, a nucleic acid delivery vehicle must exhibit low toxicity, must be efficiently taken up by cells and have a well-defined, readily manufactured formulation. As shown in clinical trials, viral vectors for delivery can result in a severely adverse, even fatal, immune response in vivo. In addition, this method has the potential to have mutagenic effects in vivo. Delivery by complexing nucleic acids in lipid complexes of different formulations (such as liposomes or cationic lipid complexes) can have toxic effects. Complexes of nucleic acids with various polymers or with peptides have shown inconsistent results and the toxicity of these formulations has not yet been resolved. Nucleic acids also have been encapsulated in polymer matrices for delivery, but in these cases the particles have a wide size range and the effectiveness for therapeutic applications has not yet been demonstrated. Such previous approaches can yield effects that are the opposite of a goal desired herein, including stimulation of the immune system. For example, when PLGA is incorporated into particles, the immune system is stimulated by the presence of the PLGA.

Therefore, there is a need for addressing the issues in the delivery of nucleic acids, and there is an ongoing need for development of microspheres and new methods for making microspheres. Details regarding microspheres, especially details regarding their preparation and properties, are found in U.S. Pat. No. 6,458,387 to Scott et al., U.S. Pat. Nos. 6,268,053, 6,090,925, 5,981,719 and 5,599,719 to Woiszwillo et al., and U.S. Pat. No. 5,578,709 to Woiszwillo and US Patent Application Publication No. 2006/0024240 to Brown et al. These and all references identified herein are incorporated by reference hereinto.

SUMMARY

In accordance with the present disclosure, oligonucleotides are delivered as microspheres. It is believed that such a delivery approach prevents access of the nucleases to the nucleic acids within the microsphere. Microsphere delivery of antisense (AS) oligonucleotides is carried out in order to induce dendritic cell tolerance, particularly in the NOD mouse model. The microspheres are fabricated using aqueous conditions such that antisense (AS) oligonucleotides are incorporated. These microspheres are used to inhibit gene expression and to prevent and/or reverse an autoimmune diabetes condition in NOD mice in vivo.

In a one aspect of the disclosure, three AS-oligonucleotides targeted to the CD40, CD80 and CD86 transcripts are synthesized, and an aqueous solution of the oligonucleotide mixture is prepared and combined with an aqueous polymer solution. Microspheres containing the oligonucleotides are formed, and these are delivered to the NOD mice by injection.

In one aspect of the disclosure, there is provided a method for reversing type 1 diabetes in a mammal comprising administering a microsphere composition wherein microspheres in the composition comprise oligonucleotides that are antisense to and targeted to bind to primary transcripts selected from the group consisting of CD40, CD80 and CD86 primary transcripts and combinations thereof. The oligonucleotides can be selected from the group consisting of SEQ ID NO:1, SEQ ID NO:2 or SEQ ID NO:3 and combinations thereof, or indeed any other oligonucleotides that target CD40, CD80 and CD86.

Another aspect of the disclosure is directed to a method of protecting beta cells of the pancreas of a mammal from autoimmune destruction, comprising injecting into the mammal a microsphere composition, wherein the microspheres in the composition comprise oligonucleotides that are antisense to and targeted to bind to primary transcripts selected from the group consisting of CD40, CD80 and CD86 primary transcripts and combinations thereof.

Another aspect is a method of decreasing T-cell-mediated inflammation of the pancreas and/or pancreatic beta cell death in a mammal comprising administering to the mammal a microsphere composition, wherein the microspheres in the composition comprise oligonucleotides that are antisense to and targeted to bind to primary transcripts selected from the group consisting of CD40, CD80 and CD86 primary transcripts, and combinations thereof, wherein the composition is administered in an amount effective to ameliorate the symptoms of Type 1 diabetes in the mammal. In more defined aspects, the composition is administered after clinical onset of Type 1 diabetes. In alternative aspects, the composition is administered prior to clinical onset of Type 1 diabetes. In these therapeutic aspects, the administration of the composition normalizes blood glucose levels in the mammal as compared to the blood glucose levels of the mammal prior to administration.

The administration of the composition may regenerate the beta cell population of the mammal or halt the further deterioration of the beta cell population or both.

The composition may be administered in any form and in certain exemplary aspects is administered as an injectable form. In specific aspects, the composition is administered in combination with insulin. Where a combination therapy is used, the insulin may be administered prior to, concurrently with, or after administration of the microsphere composition.

Additional aspects are directed to methods of preserving residual beta cell mass in a subject with new-onset or preclinical autoimmune diabetes comprising administering to the subject a composition containing microspheres comprising oligonucleotides that are antisense to and targeted to bind to CD40, CD80 and CD86 primary transcripts, wherein administration of the composition maintains the beta cell mass of the mammal to at least about 15% of the mass present prior to diabetes onset. The subject may be a human subject. The subject may be a human child. The treatment method may involve repeated administration of the composition and the repeated administration increases the beta cell mass of the mammal.

In particular defined methods, 30% and as much as 70% w/w of the microspheres is oligonucleotide. Such compositions typically may comprise a ratio in the microsphere composition of antisense CD40:antisense CD80: antisense CD86 of 1:1:1.

These and other aspects, objects, features and advantages of the present disclosure, including the various combinations, will be apparent from and clearly understood through a consideration of the following detailed description.

BRIEF DESCRIPTION OF THE DRAWINGS

In the course of this description, reference will be made to the attached drawings, wherein:

FIGS. 1 a and 1b are scanning electron micrographs of microspheres of AS-oligonucleotides and poly-L-lysine polycation.

FIGS. 2 a and 2b are graphs showing the properties of a microsphere preparation according to the disclosure. FIG. 2a is graph showing the size distribution of a preparation of microspheres. FIG. 2b shows a graph of the surface charge of a preparation of microspheres.

FIG. 3 is a RP-HPLC chromatogram of the oligonucleotides after deformulation of microspheres.

FIG. 4 is a plot showing the prevention of diabetes in NOD mice treated multiple times with antisense oligonucleotide microspheres (AS-MSP) of the disclosure compared to animals treated with scrambled oligonucleotides microspheres or with the PBS vehicle alone.

FIG. 5 is a plot showing the prevention of diabetes in NOD mice treated once with AS-MSP of the disclosure compared to animals treated with scrambled oligonucleotide microspheres or with the PBS vehicle alone.

FIGS. 6 a-6d are light micrographs of pancreatic tissue sections from control NOD mice stained with haemotoxylin and eosin (FIG. 6 and c; H+E) or for insulin (FIGS. 6b and 6d).

FIGS. 7 a-7d are light micrographs of pancreatic tissue sections from AS-MSP treated NOD mice stained with haemotoxylin and eosin (FIG. 7a and c; H+E) or for insulin (FIGS. 7b and 7d).

FIG. 8 shows a FACS analysis of T cells obtained from mice treated with the AS-MSP of the disclosure or from control animals.

FIG. 9 shows plots of relative fluorescent intensity (RFI) demonstrating the proliferation of T cells from animals treated with AS-MSP and cultured with splenocytes according to the disclosure.

FIG. 10 shows plots of RFI demonstrating the proliferation of T-cells from AS-MSP treated, diabetes-free NOD mice in the presence of syngeneic irradiated splenocytes and ovalbumin in vitro.

FIG. 11 shows plots of RFI demonstrating the suppressed proliferation of T-cells from AS-MSP-treated, diabetes-free NOD mice in the presence of syngeneic islet lysate in vitro.

FIG. 12 is a plot of blood glucose levels from new-onset diabetic mice treated with either microspheres containing antisense or scrambled oligonucleotides.

FIG. 13A shows a timeline for the experiments with mice having new-onset diabetes, and FIGS. 13B and 13C are plots of mean blood glucose levels from new-onset diabetic mice treated with either AS-MSP or controls.

FIG. 14A-C shows reversal of the type-1 diabetes phenotype in NOD mice. These figures show that upon administration of AS-MSP the blood glucose levels of the mammals return to normal within 15 days (normal levels are shown by the dashed line at approx 200 mg/dL) and remain at normal even after AS-MSP administration is stopped (day 30).

FIG. 15 Model depicting therapeutic reversal of autoimmune diabetes.

DESCRIPTION OF THE ILLUSTRATED EMBODIMENTS

As required, detailed embodiments of the present disclosure are disclosed herein; however, it is to be understood that the disclosed embodiments are merely exemplary of the disclosure, which may be embodied in various forms. Therefore, specific details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art to variously employ the present disclosure in virtually any appropriate manner.

Type I diabetes is an autoimmune disorder where there is a progressive inflammation of the pancreas, and specifically, the endocrine insulin-producing beta cells. Before onset, the inflammation first renders the endocrine beta cells dysfunctional. A single injection of a microsphere formulation considerably delays disease onset in the non-obese diabetic (NOD) mouse model of human autoimmune (type 1) diabetes. Although not wishing to be bound by any particular theory, it is believed the microspheres are taken up by resident and migrating dendritic cells at the site of injection and then move into the proximal lymph nodes before onset of the disease. It is also believed that a decreased proliferation of T-cells targeted to putative beta cell antigens in vitro occurs in treated recipients. An increase may occur in the prevalence of CD4+CD25+ putative T regulatory cells in immunodeficient NOD-scid mice reconstituted with syngeneic T-cells and dendritic cells and then administered the microspheres. Thus, a microsphere-based therapeutic composition can modulate dendritic cell activity and mobilize regulatory networks for prophylaxis.

It would be desirable to have a treatment that would prevent the onset of diabetes. It would also be desirable to have a therapeutic composition that would arrest or reverse the disease after clinical onset when a substantial number of beta cells have been destroyed. Repeated administration into new-onset diabetic mice normalizes hyperglycemia and reverses the disease. Reversal typically indicates having the individual, such as a human or other mammal, exhibit near normalization of blood glucose levels. Without being bound by any particular theory, it is believed that during “reversal”, disease-induced T-cell inflammation and cell death are resisted.

One embodiment reverses autoimmune insulin-dependent diabetes by formulating and injecting antisense (AS)-oligonucleotide microspheres described herein, targeting the transcripts of CD40, CD80 and CD86. Specific examples of antisense oligonucleotides directed against the transcripts are disclosed in the Examples hereof. It will be understood that other antisense oligonucleotides may be designed to be effective in binding the CD40, CD80 and CD86 transcripts to achieve the effects described herein. It will also be understood that such oligonucleotides may incorporate modifications known in the art including, but not limited to, thioation, methylation and methoxyethylation and that the location and number of such modifications may be varied to achieve an optimal effect. These oligonucleotides are designed to induce immune tolerance that results in the reversal of the destruction of the insulin producing beta cells in the NOD mouse model.

Type 1 diabetes is manifested by the autoimmune destruction of the pancreatic insulin-producing beta cells in the NOD mouse, as well as in humans. At the time of clinical onset, humans typically have 10-20% or less of residual beta cell mass. Sparing of any of this residual mass can result in remaining insulin levels which are adequate to regulate glucose levels. In addition, reversing the destruction of beta cells may result in the partial regeneration of the beta cell population. The oligonucleotide-containing microparticles of the present disclosure are provided to interfere with the autoimmune destruction of the beta cells.

It will be appreciated that dendritic cells (DC) can be activated to be potent antigen-presenting cells found in all tissues and which are present under the skin. These antigen-presenting dendritic cells function as triggers of the immune response, including autoimmune responses, through the activation of T-cells, particularly in lymph nodes. Although not wishing to be bound by theory, CD40, CD80 and CD86 are believed to be important for the autoimmune response, and the downregulation of these molecules is thought to promote autoimmune hyporesponsiveness. In addition, certain cytokines, such as interferons and interleukins, are reduced as a result of the hyporesponsiveness.

In making the microspheres that are used for treatment of autoimmune diabetes in mice, one, two or three AS-oligonucleotides may be dissolved in aqueous solution and combined with water soluble polymer(s) and a polycation. The solution typically is incubated at about 60-70° C., cooled to about 23° C., and the excess polymer is removed.

The nucleic acids typically comprise between about 30 and about 100 weight percent of the microspheres and have an average particle size of not greater than about 50 microns, typically not greater than about 20 microns, and can be not more than about 10 microns. Typically, they are prepared as follows. An aqueous solution of the oligonucleotide or oligonucleotides is prepared. When microspheres containing three oligonucleotides are to be prepared, aliquots from three oligonucleotide solutions are combined. Each solution contains one of these three oligonucleotide types. The final solution containing oligonucleotides typically contains about 10 mg/ml of oligonucleotide.

In specific examples, the microsphere formulation contains 65%, 70%, 75%, 80%, 85%, 90% w/w or greater load of oligonucleotides. In such embodiments, the compositions have a poly-L-lysine content of 6-10% w/w. in addition the moisture content of the microspheres varies and can be approximately 4%. The oligonucleotides are present in a ratio of 1:1:1 of antisense CD40:antisense CD80:antisense CD86.

These are combined with aliquots of a 10 mg/ml stock solution of polycation. Examples of polycations are poly-lysine and poly-ornithine. Others include polyethyleneimine (PEI), prolamine, protamine, polyvinyl pyrrolidone (PVP), polyarginine, vinylamine, and derivatives of positively-charged polysaccharides, such as positively charged chitosan, and combinations thereof. The polycation solution can be at volumetric ratios of polycation:oligonucleotide of from about 1:1 to about 4:1. Commonly used polycations include poly-L-lysine•HBr (up to 70,000 Daltons available from Bachem) and poly-L-omithine•HBr (e.g. 11,900 Daltons available from Sigma).

Polymer solutions also are prepared. These can function as phase-separation enhancing agents. Examples of suitable polymers include linear or branched polymers, copolymers and block copolymers. These polymers can be water soluble, semi-water soluble, water-miscible, or soluble in a water-miscible solvent. Examples of polymers include pharmaceutically acceptable additives such as polyethylene glycol (PEG) of various molecular weights, such as PEG 200, PEG 300, PEG 3350, PEG 8000, PEG 10000, PEG 20000, etc. and poloxamers of various molecular weights such as poloxamer 188 and Pluronic F127 or Pluronic F68. A commonly used polymer is polyvinylpyrrolidone (PVP). Another polymer is hydroxyethylstarch. Other amphiphilic polymers can also be used alone or in combinations. The phase-separation enhancing agent can also be a non-polymer such as a mixture of propylene glycol and ethanol.

In a typical embodiment, a polymer solution of polyvinyl pyrrolidone and/or of polyethylene glycol may be prepared and combined with the other solutions. Heating, cooling, centrifuging and washing multiple times provide an aqueous suspension which typically is frozen and lyophilized to form a dry powder of microspheres comprising oligonucleotide and polycation.

The microspheres are suitable for in vivo delivery by an injectable route, including intravenous, intramuscular, subcutaneous, intraperitoneal, intrathecal, epidural, intra-arterial, intra-articular and the like. Other delivery routes that can be practiced include such as topical, oral, rectal, nasal, pulmonary, vaginal, buccal, sublingual, transdermal, transmucosal, otic or intraocular.

Without being bound by any particular theory, it is believed that microspheres containing the antisense oligonucleotides exemplified herein down-regulate cell surface molecules CD40, CD80 and CD86. The microspheres are injected and dendritic cells are believed to actively uptake the oligonucleotide microspheres. These oligonucleotides suppress the expression of cell surface cell molecules CD40, CD80 and CD86 in dendritic cells. The administration of these antisense oligonucleotide microspheres after development in the NOD mouse effectively reverses diabetes.

The following Examples illustrate certain features and advantages of the disclosure in order to further illustrate the disclosure. The Examples are not to be considered limiting or otherwise restrictive of the disclosure.

EXAMPLE 1

Three AS-oligonucleotides targeted to the CD40, CD80 and CD86 primary transcripts were synthesized. The AS-oligonucleotide sequences used in this Example are, with asterisks indicating sites of thioation in the backbone:

Seq ID 1: CD 40-AS:
5′C*AC* AG*C C*GA* GG*C* AA*A GA*C* AC*C A*T*G
C*AG* GG*C* A-3′
Seq ID 2: CD80-AS:
5′-G*GG* AA*A G*CC* AG*G A*AT* CT*A G*AG* CC*A
A*TG G*A-3′
Seq ID 3: CD86-AS:
5′-T*GG* GT*G C*TT* CC*G T*AA* GT*T C*TG* GA*A
C*AC* G*T*C_3′

An aqueous solution of the oligonucleotide mixture was prepared by combining aliquots of three oligonucleotide solutions, each of which contained one type of oligonucleotide, to form a 10 mg/ml solution of the three types of oligonucleotides. A 10 mg/ml solution of poly-L-lysine•HBr in deionized water (poly-L-lysine•HBr up to 70,000 Daltons, by Bachem, King of Prussia, Pa.) was prepared. The poly-L-lysine•HBr was added to the oligonucleotides solution at a volumetric ratio of 1:1. The mixture was vortexed gently. A 25% polymer solution containing 12.5% PVP (polyvinyl pyrrolidone, 40,000 Daltons, Spectrum Chemicals, Gardena, Calif.) and 12.5% PEG (polyethylene glycol, 3,350 Daltons, Spectrum Chemicals, Gardena, Calif.) in 1M Sodium Acetate (Spectrum, Gardena, Calif.) at pH5.5 was added in a 2:1 volumetric ratio as follows: 0.75 ml of AS-oligonucleotides, 0.75 ml of poly-L-lysine•HBr, 3.0 ml of PEG/PVP, and a total volume of 4.50 ml.

The batch was incubated for 30 minutes at 70° C. and then cooled to 23° C. Upon cooling, the solution became turbid and microspheres were formed. The suspension was then centrifuged, and the excess PEG/PVP was removed. The resulting pellet was washed by resuspending the pellet in deionized water, followed by centrifugation and removal of the supernatant. The washing process was repeated three times. The aqueous suspension was frozen and lyophilized to form a dry powder of microspheres comprising oligonucleotide and poly-L-lysine.

FIGS. 1 a and b present representative scanning electron micrographs (SEM) of 1:1 poly-L-lysine: oligonucleotide ratio microspheres at two different magnifications. Microspheres, 0.5-4 μm in size, with an average particle size of approximately 2.5 μm were fabricated. FIG. 2a shows the size distribution of one preparation of microspheres made according to the disclosure as revealed by laser light scattering. FIG. 2b shows the determination of the surface charge of a microsphere preparation (Zeta potential) by light scattering. FIG. 3 shows a reverse phase (RP) HPLC method used to quantitate the loading and assess the integrity of the antisense oligonucleotide components of the microspheres after deformulation. Microspheres were formulated using CD86, CD40, CD80 oligonucleotides and poly-L-lysine (PLL; MW 30-70 kD). The microspheres were then deformulated using competitive displacement of the DNA oligonucleotides from the PLL by poly-L-aspartic acid (PAA). PAA was selected as a polyamino acid reagent that does not absorb at 260 nm and does not interfere with quantification of oligonucleotides at 260 nm. In RP-HPLC profiles such as FIG. 3, the area under each peak is proportional to amount of each oligonucleotide loaded into the microsphere. As shown in FIG. 3, the peak heights indicate approximately equal loading of each oligonucleotide into microspheres. The loading of oligonucleotides into microspheres was calculated to be from about 65% to about 80% by weight. FIG. 3 also shows that the integrity of the oligonucleotides was not affected by the microsphere formulation process, as indicated by the narrow distribution of the peaks after deformulation.

EXAMPLE 2

In this Example, the results of tests that cover prevention aspects of the disclosure are shown. As shown in FIG. 4, a single AS-MSP administration into NOD mice at 5-8 weeks of age delays diabetes onset. Two groups of NOD female mice (5-8 weeks old) were given a single subcutaneous injection of antisense-oligonucleotides formulated into microspheres of the disclosure (AS-MSP). The formulation was injected in injected in an amount considered to contain 50 μg of a 1:1:1 mixture of each antisense oligonucleotide (anti-CD40, anti-CD80 and anti-CD86). Other groups of mice were injected with scrambled sequence microspheres (SCR-MSP) or PBS vehicle (control NOD). Blood glucose was measured weekly via tail vein puncture. Diabetes was confirmed after two consecutive readings of >280-300 mg/dL. FIG. 4 shows the cumulative survival of two independently-treated cohorts.

FIG. 5 shows that multiple AS-MSP administration into NOD mice at 5-8 weeks of age prevents diabetes onset. NOD female mice (5-8 weeks old) were given eight consecutive single subcutaneous injections (once weekly) of antisense oligonucleotide formulated into microspheres according to the disclosure. Injections (50 μg of a 1:1:1 mixture of each antisense oligonucleotides or scrambled oligonucleotides) were given once weekly for eight weeks and stopped at week 13. Other groups of mice were injected with scrambled sequence microspheres (SCR-MSP) or PBS vehicle (control NOD). FIG. 5 shows the cumulative survival of treated animals.

FIGS. 6 a and 6b show sections of pancreatic tissue from mice that received no treatment and thus progress spontaneously to autoimmunity (diabetic NOD mice) stained with haemotoxylin and eosin (H+E; FIG. 6a) or stained for insulin (FIG. 6b). FIG. 6c and 6d show sections of pancreatic tissue from mice treated with SCR-MSP formulations (injections started in parallel with the groups treated with specific AS-MSP). These sections were also stained with haemotoxylin and eosin (H+E; FIG. 6c) or stained for insulin (FIG. 6d). The SCR-MSP mice all developed diabetes.

FIGS. 7 a and 7b shows sections of pancreatic tissue from mice treated when less than 8 weeks of age (prevention model) and treated with the antisense microspheres of the disclosure stained with haemotoxylin and eosin (H+E; FIG. 7a) or stained for insulin (FIG. 7b).

As shown in FIG. 8, T-cells from AS-MSP treated, NOD mice exhibit increased prevalence of Foxp3+ CD25+ putative T_reg cells. FIG. 8A shows the gating used for FACS analysis. FIG. 8B shows percentages of Foxp3+ CD25+ T-cells that were enriched from the spleen and FIG. 8C the percentages from the pooled lymph nodes for ASMSP-treated diabetes-free mice selected at random from the ASMSP diabetes-free cohort or from or from animals treated with scrambled sequence microspheres (SCR-MSP) or treated with PBS vehicle.

FIG. 9 shows that T-cells from ASMSP-treated diabetes-free NOD mice proliferate when co-cultured with allogeneic splenocytes. T-cells from diabetes-free NOD mice treated with ASMSP were obtained over enrichment columns and co-cultured with γ-irradiated splenocytes from Balb/c, C57BL6 or syngeneic diabetes-free NOD mice (10 weeks of age). Proliferation was measured four days later using the Cyquant reagent. Spl refers to allogeneic irradiated splenocytes.

As shown in FIG. 10, T-cells from ASMSP-treated, diabetes-free NOD mice proliferate in the presence of syngeneic irradiated splenocytes and ovalbumin in vitro. T-cells were enriched from the spleen or the pooled lymph nodes of ASMSP-treated diabetes-free mice selected at random from the ASMSP diabetes-free cohort.

FIG. 11 shows that T-cells from ASMSP-treated, diabetes-free NOD mice exhibit suppressed proliferation in the presence of syngeneic islet lysate in vitro. T-cells were enriched from the spleen or the pooled lymph nodes of ASMSP-treated diabetes-free mice selected at random from the ASMSP diabetes-free cohort as described in FIG. 4. Irradiated NOD splenocytes (from diabetes-free 10 week-old NOD mice) were used as antigen-presenting cells and parallel cultures were pulsed with NIT-1 lysate (1 μg/well)(or PBS vehicle).

A major concern for eventual translation of diabetes-suppressive therapies into human trials is the antigen specificity (and therefore the cell specificity) of the treatment approach and whether the treatment confers global and non-specific suppression. To address these issues, randomly-selected diabetes-free mice were euthanised from the cohorts shown in FIG. 4 to ascertain the proliferation of splenic and lymph node T-cells to alloantigen, nominal antigen (in the form of intact ovalbumin) and to syngeneic beta cell-derived antigen in the form of cell lysate from the NOD derived insulinoma cell line NIT-1. While insulin and glutamic acid decarboxylase (GAD) are viable candidate autoantigens with mechanistic and teleologic involvement, the nature of the initiating autoantigen remains unclear. Nevertheless, it is reasonable to consider that it should be beta-cell resident. Therefore, the NIT-1 cell line which derives from an NOD insulinoma was used as a source of beta cell antigen in cocultures of T-cells from diabetes-free NOD mice treated with the AS-MSP to determine the possibility of antigen-specific hyporesponsiveness. From these studies, it was seen that T-cell proliferation to nominal and alloantigen is maintained whereas there is T-cell hypoproliferation in cocultures with NIT-1 cell lysate.

Furthermore, ascertaining the cytokine profile in the co-culture supernatants, we observed a significant decrease in TNFα production by T-cells from AS-MSP-treated, diabetes-free NOD mice even in the presence of NIT-1 lysate. Although IFNγ production was slightly decreased in the co-cultures of T-cells from the AS-MSP-treated mice, it was not statistically-distinguishable from the co-cultures with T-cells from PBS-treated mice in the presence of NIT-1 lysate. The assay, finally, could not detect the presence of IL-4, IL-10 or TGFfβ in the supernatants.

EXAMPLE 3

The ability of antisense oligonucleotide microspheres to reverse the symptoms of diabetes in early onset NOD mice was also tested. A timeline for these experiments is shown in FIG. 13A. NOD mice that had early onset were selected by testing blood glucose levels and identifying animals that had a blood glucose level greater than 400 mg/dL. The selected animals were given insulin pellets to normalize blood glucose levels to below 300 mg/dL. The insulin was withdrawn and a series of parenteral injections of microspheres was started. Six animals were injected twice weekly with microspheres containing the CD40, CD80 and CD86 antisense oligonucleotides. A further ten animals were injected with microspheres containing a mixture of oligonucleotides with scrambled sequences that are not directed against CD40, CD80 and/or CD86. Each injection for both groups of animals contained 50 μg of oligonucleotides in microspheres in 100 microliters of injection solution. Two of the animals in the scrambled group were euthanized before the end of the experiment due to poor physical condition. After the commencement of the injection protocol, blood glucose levels were sampled twice weekly. The animals were non-fasting during the experiment. The results are plotted in FIG. 12, wherein the indicator (1) signifies insulin pellet installation and indicator (2) signifies insulin pellet removal and initiation of MSP injections twice weekly. It is noted that the maximum blood glucose value reported in FIG. 12 is 700 mg/dL, which corresponds to the maximum reading of the meter used, it being understood that a 700 mg/dL data point indicates a blood glucose reading of 700 mg/dL or higher, All animals in the group that received the microspheres containing the mixture of CD40, CD80, CD86 antisense oligonucleotides (ASMSP1 through ASMSP6) showed significantly lower glucose levels than the animals that received the microspheres with scrambled oligonucleotides (SCRMSP1 through SCRMSP10). Furthermore, four of six animals in this ASMSP group showed a blood glucose level below 400 mg/dL, typically considered to be a threshold indicator of diabetes onset.

In FIG. 13A, the timeline for the experiments is shown. The mean non-fasting blood glucose (FIG. 13B) and the mean fasting blood glucose levels for each group are plotted (FIG. 13C) (+/− SEM). In some mice, ASMSP administration was withdrawn as shown in FIG. 13A. As shown in FIG. 13B and 13C, multiple rounds of AS-MSP administration into new-onset diabetic NOD female mice improves blood glucose levels and result in stable fasting euglycemia even after AS-MSP withdrawal relative to untreated animals (control), animals treated with PBS or animals treated with scrambled oligonucleotides (SCR-MSP) microspheres.

FIGS. 7 c and 7d show sections of pancreatic tissue from NOD mice that were treated with antisense formulations after onset of diabetes and showed reversal of the disease. The sections are stained with haemotoxylin and eosin (H+E; FIG. 7c) or stained for insulin (FIG. 7d).

3 different AS-oligonucleotides can be incorporated into PROMAXX microspheres and such microspheres can be used as a composition to prevent and/or reverse new onset autoimmune diabetes via immunoregulatory dendritic cell induction. Indeed, a single injection of the composition delayed disease onset and repeated administration into new-onset diabetic mice normalized hyperglycemia, suggesting reversal of disease. In these studies, insulin was administered daily until blood glucose fell below 300 mg/dL. Insulin then was stopped whereupon AS-MSP were administered subcutaneously. In an exemplary dosing regiment, the animals were administered 2 mg AS-MP per kg body weight two times a week for 3-4 weeks. The diabetes-free NOD mice were monitored.

In FIG. 14A-C it is demonstrated that administration of AS-MSP to NOD mice returns the blood glucose levels of said mice to normal levels and the normalization of said blood glucose level is maintained for an extended period of time. As shown in FIG. 14B and 14C, AS-MSP was administered between days 0-30 after insulin administration was stopped. The blood glucose level returned to normal by day 15 post insulin stop and remained at a normal level until the end of the monitoring period (day 55).

A diagram showing the impact of therapeutic reversal of autoimmune diabetes is show in FIG. 15. If PROMAXX treatment were administered at the new onset “honeymoon” shown in FIG. 15, it is predicted that there would be a preservation of the 10-20% beta cells that remain functional, thereby leading to a control of the diabetes and reducing the dependence of the patient on insulin.

It will be understood that the embodiments of the present disclosure which have been described are illustrative of some of the applications of the principles of the present disclosure. Numerous modifications may be made by those skilled in the art without departing from the true spirit and scope of the disclosure. Various features which are described herein can be used in any combination and are not limited to precise combinations which are specifically outlined herein.

Claims

1. A method for reversing Type 1 diabetes in a mammal comprising administering a microsphere composition directly to the mammal, wherein microspheres in said composition comprise oligonucleotides that are antisense to and targeted to bind to primary transcripts selected from the group consisting of CD40, CD80 and CD86 primary transcripts, and combinations thereof, and wherein administration of the microsphere composition promotes autoimmune hyporesponsiveness in the mammal.

2. The method of claim 1, wherein said oligonucleotides are selected from the group consisting of SEQ ID NO:1, SEQ ID NO:2 or SEQ ID NO:3 and combinations thereof.

3. The method of claim 1, wherein said composition is administered after clinical onset of Type 1 diabetes.

4. The method of claim 1, wherein said composition is administered prior to clinical onset of Type 1 diabetes.

5. The method of claim 1, wherein administration of said composition normalizes blood glucose levels in said mammal as compared to the blood glucose levels of said mammal prior to administration.

6. The method of claim 1, wherein said method comprises administration of a composition containing microspheres that comprising oligonucleotides that are antisense to and targeted to hind to CD40, CD80 and CD86 primary transcripts.

7. The method of claim 1, wherein said composition is administered as an injectable form.

8. The method of claim 1, wherein said composition is administered in combination with insulin.

9. The method of claim 8, wherein said insulin is administered prior to, concurrently with, or after administration of said microsphere composition.

10. The method of claim 1, wherein 70% w/w of said microspheres is oligonucleotide.

11. The method of claim 10, wherein the ratio in said microsphere composition of antisense CD40: antisense CD80: antisense CD86 is 1:1:1.