Antibody that specifically binds to CD38, method for preparing the same, and use thereof

Abstract

The present invention provides anti-CD38 nanobodies or their binding fragments. The antibodies exhibit good specificity. Furthermore, the antibodies, and CD38-targeted immune effector cells prepared using the antibodies, demonstrate good therapeutic efficacy in treating or alleviating diseases exhibiting CD38-positive expression.

Claims

1. A nanobody that specifically binds to CD38, wherein the complementarity determination region (CDR) of the VHH chain of the nanobody includes the following CDR1, CDR2, and CDR3: (a) CDR1: Its sequence is as shown in sequence number 6 or 11, (b) CDR2: Its sequence is as shown in sequence numbers 7, 9, 12, or 14, (c) CDR3: a nanobody whose sequence is as shown in sequence numbers 8, 10, 13, or 15.

2. The complementarity determination region (CDR) of the VHH chain of the nanobody is as follows: (Y1) CDR1 as shown in Sequence ID 6, CDR2 as shown in Sequence ID 14, and CDR3 as shown in Sequence ID 15, (Y2) CDR1 as shown in Sequence ID 6, CDR2 as shown in Sequence ID 9, and CDR3 as shown in Sequence ID 10, (Y3) CDR1 as shown in Sequence ID 6, CDR2 as shown in Sequence ID 7, and CDR3 as shown in Sequence ID 8, (Y4) CDR1 as shown in Sequence ID 6, CDR2 as shown in Sequence ID 9, and CDR3 as shown in Sequence ID 10, (Y5) The nanobody according to claim 1, selected from the group consisting of CDR1 as shown in Sequence ID No. 11, CDR2 as shown in Sequence ID No. 12, and CDR3 as shown in Sequence ID No.

13.

3. The nanobody according to claim 1, wherein the amino acid sequence of the nanobody that specifically binds to the CD38 is as shown in any one of sequence numbers 1 to 5.

4. A multivalent antibody or multiepitope-targeted antibody that specifically binds to CD38, wherein the multivalent antibody or multiepitope-targeted antibody comprises at least one antibody component that targets CD38, and the antibody component is an anti-CD38 nanobody as described in claim 1.

5. Recombinant protein, wherein the recombinant protein is (i) a nanobody that specifically binds to CD38 as described in claim 1, or a polyvalent antibody that specifically binds to CD38 as described in claim 4, or a multiepitope-targeted antibody, (ii) Recombinant protein comprising a tag sequence that promotes optional expression and / or purification.

6. A chimeric antigen receptor (CAR) fusion protein, wherein the chimeric antigen receptor (CAR) fusion protein is arranged from the N-terminus to the C-terminus, (i) an antigen-binding domain that specifically binds to CD38, comprising the nanobody described in claim 1, (ii) Transmembrane domain, (iii) at least one co-stimulatory domain, and (iv) A chimeric antigen receptor (CAR) fusion protein containing an activating domain.

7. The CAR has the structure shown in formula Ia: L-VHH-F-H-TM-C-CD3ζ (Ia) During the ceremony, Each "-" independently represents a linker peptide or peptide bond. L is the signal peptide sequence, VHH is an antigen-binding domain that specifically binds to CD38, and the amino acid sequence of VHH is as shown in any one of SEQ ID NOs: 1 to 5. F is a Flag tag. H is the hinge region, TM is a transmembrane domain, C is a co-stimulatory signaling domain, and The CAR fusion protein according to claim 6, wherein CD3ζ is a cytoplasmic signaling sequence derived from CD3ζ (including wild-type or its variants / modified versions).

8. The CAR fusion protein according to claim 6, wherein the CAR fusion protein has the amino acid sequence shown in any one of SEQ ID NOs. 25 to 29.

9. An antibody-drug conjugate, wherein the antibody-drug conjugate is (a) a nanobody according to claim 1, a multivalent antibody according to claim 4, or a multiepitope-targeted antibody, or a recombinant protein according to claim 5, (b) An antibody-drug conjugate comprising a conjugate portion conjugated to the antibody portion, wherein the conjugate portion is selected from the group consisting of a detectable label, a drug, a toxin, a cytokine, a radionuclide, an enzyme, or a combination thereof.

10. A polynucleotide characterized by encoding a protein, selected from the group consisting of a nanobody as described in claim 1, a polyvalent antibody or multiepitope-targeted antibody as described in claim 4, a recombinant protein as described in claim 5, or a CAR fusion protein as described in claim 6.

11. An expression vector, characterized in that the expression vector comprises the polynucleotide described in claim 10.

12. A host cell, wherein the host cell contains the expression vector described in claim 11, or has a polynucleotide described in claim 10 incorporated into its genome, or expresses a nanobody described in claim 1, a multivalent antibody described in claim 4, or a multiepitope-targeted antibody, a recombinant protein described in claim 5, or a CAR fusion protein described in claim 6.

13. A pharmaceutical composition, wherein the pharmaceutical composition is (i) an immune cell expressing the nanobody described in claim 1, the multivalent antibody or multiepitope-targeted antibody described in claim 4, the recombinant protein described in claim 5, or the CAR fusion protein described in claim 6, and (ii) A pharmaceutical composition comprising a pharmaceutically acceptable carrier.

14. Use of immune cells expressing the nanobody described in claim 1, the multivalent antibody or multiepitope-targeted antibody described in claim 4, the recombinant protein described in claim 5, or the CAR fusion protein described in claim 6, wherein the use is for the preparation of drugs for the prevention and / or treatment of diseases related to CD38 positive expression.

15. A method for treating a disease, characterized by administering immune cells expressing the nanobody described in claim 1, the multivalent antibody or multiepitope-targeted antibody described in claim 4, the recombinant protein described in claim 5, or the CAR fusion protein described in claim 6 to a subject in need of treatment.

Images