Abstract: The invention provides modified heavy chain constant regions including a cysteine at position 295 by EU numbering and optionally at position 239 by EU numbering. These cysteine residues provide sites for conjugation to a drug or label. When both cysteines are present in a normal heterodimeric antibody format, there are four such sites per molecule of antibody allowing a stoichiometry of one molecule of antibody to four of drug or label. Selection of the cysteine at position 295 with or without cysteine at position 239 is advantageous over cysteines at many other positions due to ease of expression, stability and cytotoxicity.

Abstract: A method of preventing, reducing a risk of, or treating a virus infection, or preventing or treating a symptom caused by the virus in a subject, said method comprising administering to said subject an effective amount of a fusion protein, wherein the fusion protein comprises a variant angiotensin converting enzyme 2 (ACE2) domain covalently fused to a Fc domain. The variant ACE2 domain comprises a N-terminal deletion, a C-terminal deletion, or both, relative to a full-length wildtype ACE2 having a SEQ ID NO. 1, and the variant ACE2 domain has ACE2 activity. The virus may be SARS-CoV, SARS-CoV-2, or MERS-CoV. The symptom comprises Severe Acute Respiratory Syndrome (SARS), Middle East Respiratory Syndrome (MERS), Acute Respiratory Distress Syndrome (ARDS), Pulmonary Arterial Hypertension (PAH), or Coronavirus Disease 2019 (COVID-19).

Abstract: Provided are novel anti-CD228 antibodies and antibody-drug conjugates and methods of using such anti-CD228 antibodies and antibody-drug conjugates to treat cancer.

Abstract: A fusion protein, comprising a variant angiotensin converting enzyme 2 (ACE2) domain covalently fused to a Fc domain. The variant ACE2 domain has a N-terminal deletion, a C-terminal deletion, or both, relative to a full-length wildtype ACE2 having a SEQ ID NO: 1. The variant ACE2 domain has ACE2 activity.

Abstract: The application provides multi-specific antibody-like proteins may comprising one or more binding domains including a first binding domain (D1), a second binding domain (D2), a third binding domain (D3), a fourth binding domain (D4), a fifth binding domain (D5), or a sixth binding domain (D6). The multi-specific antibody-like protein disclosed herein may be mono-specific, bi-specific, tri-specific, tetra-specific, penta-specific or hexa-specific. The binding domains such as D1, D2, D3, D4, D5, and D6 may each independently have a binding affinity to specificity against a T cell activating receptor, an immune cell receptor, an immune checkpoint molecule, a co-stimulation factor, a receptor of a leukocyte, a tumor antigen, a tumor associated antigen (TAA), a receptor of a tissue cell, a receptor of a cancer cell, or a combination thereof.

Abstract: A multi-specific antibody-like protein having a first monomer comprising a first binding monomer, a CH1 domain, a first hinge, a first CH2 domain, and a first CH3 domain, a second monomer comprising a second binding monomer, a CL domain, a second hinge, a second CH2 domain, and a second CH3 domain, wherein the first binding monomer and a second binding monomer are configured to form a dimer, wherein the first monomer and the second monomer are covalently paired through at least one disulfide bond between the CH1 domain and the CL domain and at least one disulfide bond between the first hinge and the second hinge, wherein the first monomer and second monomer may comprise optionally a first binding domain (D1) and a second binding domain (D2), and a fourth binding domain (D4) and a fifth binding domain (D5), and wherein the multi-specific antibody-like protein is at least bi-specific.

Abstract: An isolated monoclonal antibody (mAb) or antigen-binding fragment thereof having a binding specificity to human CD19, wherein the isolated mAb or antigen-binding fragment comprises an amino acid sequence having an identity with a sequence selected from SEQ ID NO. 1, 3, 5, 7, 9, 11, 13, 15, 17, 19, 21, 23, 91, or 93, wherein the identity is not less than at least 95%.

Abstract: The application provides a multi-specific antibody-like protein having a N-terminal and a C-terminal, comprising in tandem from the N-terminal to the C-terminal, a first binding domain (D1) at the N-terminal, a second binding domain (D2) comprising a light chain moiety, a Fc region, a third binding domain (D3), and a fourth binding domain (D4) at the C-terminal, wherein the light chain moiety comprises a fifth binding domain (D5) covalently attached to the C-terminal, a sixth binding domain (D6) covalently attached to the N-terminal, or both, and wherein the D1, D2, D3, D4, D5 and D6 each has a binding specificity against a tumor antigen, an immune signaling antigen, or a combination thereof.

Abstract: The invention provides modified heavy chain constant regions including a cysteine at position 295 by EU numbering and optionally at position 239 by EU numbering. These cysteine residues provide sites for conjugation to a drug or label. When both cysteines are present in a normal heterodimeric antibody format, there are four such sites per molecule of antibody allowing a stoichiometry of one molecule of antibody to four of drug or label. Selection of the cysteine at position 295 with or without cysteine at position 239 is advantageous over cysteines at many other positions due to ease of expression, stability and cytotoxicity.

Abstract: Provided are novel anti-PD-L1 antibodies and antibody-drug conjugates and methods of using such anti-PD-L1 antibodies and antibody-drug conjugates to treat cancer.