Immunostimulatory nucleic acid molecules for activating dendritic cells

Abstract

The present invention relates generally to methods and products for activating dendritic cells. In particular, the invention relates to oligonucleotides which have a specific sequence including at least one unmethylated CpG dinucleotide which are useful for activating dendritic cells. The methods are useful for in vitro, ex-vivo, and in vivo methods such as cancer immunotherapeutics, treatment of infectious disease and treatment of allergic disease.

Description

RELATED APPLICATIONS [0001] This application is a divisional of co-pending U.S. Ser. No. 09 / 191,170, filed on Nov. 13, 1998, now allowed which is a continuation-in-part of U.S. Ser. No. 08 / 960,774, filed Oct. 30, 1997, now issued as U.S. Pat. No. 6,239,116B1 on May 29, 2001, which is a continuation-in-part of U.S. Ser. No. 08 / 738,652, filed Oct. 30, 1996 and which is now issued as U.S. Pat. No. 6,207,646B1 on Mar. 27, 2001, and which patent is a continuation-in-part of U.S. Ser. No. 08 / 386,063, filed Feb. 7, 1995 and which is now issued as U.S. Pat. No. 6,194,388B1 on Feb. 27, 2001, and which patent is a continuation-in-part of U.S. Ser. No. 08 / 276,358, filed Jul. 15, 1994 and which is abandoned, each of which are incorporated by reference.FIELD OF THE INVENTION [0002] The present invention relates generally to methods and products for activating dendritic cells. In particular, the invention relates to oligonucleotides which have a specific sequence including at least one unmethylat...

AI Technical Summary

Benefits of technology

[0010] As described in co-pending parent patent application U.S. Ser. No. 08 / 960,774 the vertebrate immune system has the ability to recognize the presence of bacterial DNA based on the recognition of so-called CpG-motifs, unmethylated cytidine-guanosine dinucleotides within specific patterns of flanking bases. According to these disclosures CpG functions as an adjuvant and is as potent at inducing B-cell and T-cell responses as the complete Freund's adjuvant, but is preferable since CpG induces a higher Th1 response and is less toxic. Alum, the adjuvant which is used routinely in human vaccination, induces the less favorable Th2 response. Compared to alum, CpG is a more effective adjuvant. The combination of CpG and alum was found to produce a synergistic adjuvant effect.

[0011] CpG oligonucleotides also show adjuvant effects towards various immune cells. For instance, CpG enhances the efficacy of monoclonal antibody therapy, thus functioning as an effective immune adjuvant for antigen immunization in a B cell lymphoma model. Cytotoxic T cell responses to protein antigen also are induced by CpG. Furthermore, the presence of immunostimulatory DNA sequences in plasmids was found to be necessary for effective intradermal gene immunization.

[0012] It was discovered according to an aspect of the invention that the adjuvant activity of CpG is based on the direct activation of dendritic cells by CpG. Potent immunostimulatory CpG oligonucleotides and control oligonucleotides were found to cause dramatic changes in dendritic cells isolated from peripheral blood by immunomagnetic cell sorting. CpG oligonucleotides provided excellent Dendritic cell survival, differentiation, activation and maturation, and were superior to the combination of GM-CSF and LPS. In fact, the combination of CpG and GM-CSF produced unexpected synergistic effects on the activation of dendritic cells. The invention thus encompasses both CpG oligonucleotides and the combination of CpG oligonucleotides and cytokines such as GM-CSF as well as in vitro, ex vivo, and in vivo methods of activating dendritic cells for various assays and immunotherapeutic strategies.

Problems solved by technology

Unfortunately, toxic side effects has thus far prevented poly(IC) from becoming a useful therapeutic agent.

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