The disclosure provides methods of determining patient populations amenable or suitable for immunomodulatory treatment of disease such as cancer by measuring the relative or absolute levels of T-cell sub-populations correlated with disease such as cancer.

Methods of using detection of PD-L1 expression by circulating cancer cells in the screening, monitoring, treatment and diagnosis of cancer in subjects are disclosed. The methods are based on assaying one or more of circulating tumor cells (CTCs), epithelial to mesenchymal transition CTCs (EMTCTCs), cancer associated macrophage-like cells (CAMLs), and cancer associated vascular endothelial cells (CAVEs) isolated from a subject having cancer for PD-L1 expression.

The present invention relates to means and methods for determining whether a patient is in need of a PD-L1 inhibitor cotherapy. A patient is determined to be in need of the PD-L1 inhibitor cotherapy if a low or absent ER expression level and an expression level of programmed death ligand 1 (PD-L1) that is increased in comparison to a control is measured in vitro in a sample from the patient. The patient is undergoing therapy comprising a modulator of the HER2/neu (ErbB2) signaling pathway (like Trastuzumab) and a chemotherapeutic agent (like dodetaxel) or such a therapy is contemplated for the patient. Also provided herein are means and methods for treating a cancer in a cancer patient for whom therapy comprising a modulator of the HER2/neu (ErbB2) signaling pathway (like Trastuzumab) and a chemotherapeutic agent (like dodetaxel) is contemplated, wherein the patient is to receive PD-L1 inhibitor cotherapy.

Provided herein are biomarkers for the treatment of pathological conditions, such as cancer, and method of using PD-1/PD-L1 pathway antagonists. In particular, provided are biomarkers for patient selection and prognosis in cancer, as well as methods of therapeutic treatment, articles of manufacture and methods for making them, diagnostic kits, methods of detection and methods of advertising related thereto.

Provided are anti-PD-L1 antibodies, variants, mutants, and antigen binding fragments thereof. Also provided are isolated nucleic acid molecules that encode the anti-PD-L1 antibodies, variants, mutants, or antigen binding fragments thereof, and related expression vectors, and host cells. Provided are methods of making anti-PD-L1 antibodies, variants, mutants, and antigen binding fragments thereof. Also provided are related pharmaceutical compositions and methods of their use to treat subjects. This abstract is intended as a scanning tool for purposes of searching in the particular art and is not intended to be limiting of the present disclosure.

Methods are provided for assaying neoplastic cells and/or neoplasia-related cells. Aspects of the methods involve detecting heterogeneity, per cell programmed-death ligand 1 (PD-L1) expression, and/or proliferation of neoplasia and/or neoplasia-related cells. Aspects of the methods include cytometrically assaying a labeled cell suspension to quantify per cell heterogeneity, per cell PD-L1 expression, proliferation, and/or other parameters to detect whether a neoplastic cell is present in the neoplasia sample. Aspects of the provided methods also include treating a subject based on the outcome of such an assay. In addition, kits that find use in practicing the subject methods are also provided.

The present invention relates to a novel single-domain antibody and a fragment thereof that specifically bind to PD-L1 and a composition comprising the antibody or the fragment thereof. In addition, the present invention relates to a nucleic acid encoding the antibody or the fragment thereof, a host cell comprising the nucleic acid, and related uses. Furthermore, the present invention relates to therapeutic and diagnostic uses of the antibody and the fragment thereof. In particular, the present invention relates to combination therapies of these antibodies and the fragments thereof with other therapies, such as therapeutic modalities or therapeutic agents.

Systems and methods are presented that allow for predicting treatment response of a tumor to a checkpoint inhibitor. In one exemplary aspect, the treatment response is directly associated with a relatively high number of patient- and tumor-specific immunologically visible neoepitopes. Specific mutational patterns in the nucleic acid encoding the neoepitope may be further indicative of treatment response.

Provided herein are novel .sup.10Fn3 domains which specifically bind to PD-L1, as well as imaging agents based on the same for diagnostics.

The present invention provides a newly identified B7 receptor, zB7R1 that functions as lymphocyte inhibitory receptor, which is a PD-1-like molecule and is expressed on T cells. The present invention also provides the discovery of zB7R1's ability to bind to CD155. Methods and compositions for modulating zB7R1-mediated negative signaling and interfering with the interaction of its counter-receptor for therapeutic, diagnostic and research purposes are also provided.