The present invention relates to methods of treating or preventing cancer and other diseases using molecules, particularly polypeptides, more particularly immunoglobulins (e.g., antibodies), comprising a variant Fc region, wherein said variant Fc region comprises at least one amino acid modification relative to a wild-type Fc region, which variant Fc region binds an FcγR that activates a cellular effector (“FcγR.sub.Activating,” such as FcγRIIA or FcγRIIIA) and an FcγR that inhibits a cellular effector (“FcγR.sub.Inhibiting,” such as FcγRIIA) with an altered Ratio of Affinities relative to the respective binding affinities of such FcγR for the Fc region of the wild-type immunoglobulin. The methods of the invention are particularly useful in preventing, treating, or ameliorating one or more symptoms associated with a disease, disorder, or infection where either an enhanced efficacy of effector cell function mediated by FcγR is desired (e.g., cancer, infectious disease) or an inhibited effector cell response mediated by FcγR is desired (e.g., inflammation, autoimmune disease).

The present invention relates to Chimeric Antigen Receptors (CAR) that are recombinant chimeric proteins able to redirect immune cell specificity and reactivity toward CLL1 positive cells. The engineered immune cells endowed with such CARs are particularly suited for immunotherapy for treating cancer, in particular leukemia.

Disclosed herein is a phage-displayed single-chain variable fragment (scFv) library, that comprised a plurality of phage-displayed scFvs characterized with (1) a specific CS combination; (2) a specific distribution of aromatic residues in each CDR; and (3) a specific sequence in each CDR. The present scFv library could be used to efficiently produce different antibodies with binding affinity to different antigens. Accordingly, the present disclosure provides a potential means to generate different antigen-specific antibodies promptly in accordance with the need in experimental researches and/or clinical applications.

The invention features combination therapies using an IL-15-based superagonist complex and an antibody to effectively treat subjects with cancer and infectious diseases.

Provided are proteins comprising a variant IgG Fc region, wherein the proteins exhibit significantly reduced binding to human FcγRI when compared with a reference protein comprising the amino acid substitutions L234A/L235A/P329G. Also provided are compositions, methods of treatment and methods to reduce Fc-induced effector functions in a parent protein.

The invention provides anti-cluster of differentiation 3 (CD3) antibodies and methods of using the same.

Provided herein are inhibitory chimeric antigen receptor compositions and cells comprising such compositions. Also provided are methods of using inhibitory chimeric antigen receptors and cells.

Provided are methods and compositions for obtaining functionally enhanced derivative effector cells obtained from directed differentiation of genomically engineered iPSCs. The derivative cells provided herein have stable and functional genome editing that delivers improved or enhanced therapeutic effects. Also provided are therapeutic compositions and the use thereof comprising the functionally enhanced derivative effector cells alone, or with antibodies or checkpoint inhibitors or additional cells in combination therapies.

The present disclosure provides a site-specific protein conjugate and the method for preparation of the same. The protein conjugate comprising a protein and an oligosaccharide, wherein said oligosaccharide comprises

##STR00001##

wherein: said GlcNAc is directly or indirectly linked to an amino acid of said protein; said Gal is a galactose; said (Fuc) is a fucose, b is 0 or 1; said Fuc* comprises a fucose or a fucose derivative linked to a molecule of interest (MOI), said protein comprises an antigen binding fragment and/or a Fc fragment.

Disclosed are antigen binding polypeptides and antigen binding polypeptide complexes (e.g., antibodies and antigen binding fragments thereof) having certain structural features. Also disclosed are polynucleotides and vectors encoding such polypeptides and polypeptide complexes; chimeric antigen receptors (CARs), cells, pharmaceutical compositions and kits containing such polypeptides and polypeptide complexes; and methods of using such polypeptides and polypeptide complexes.