Development of a potent high-affinity human therapeutic antibody via novel application of recombination signal sequence-based affinity maturation.

Therapeutic antibody development requires discovery of an antibody molecule with desired specificities and drug-like properties. For toxicological studies, a therapeutic antibody must bind the ortholog antigen with a similar affinity to the human target to enable relevant dosing regimens, and antibodies falling short of this affinity design goal may not progress as therapeutic leads. Herein, we report the novel use of mammalian recombination signal sequence (RSS)-directed recombination for complementarity-determining region-targeted protein engineering combined with mammalian display to close the species affinity gap of human interleukin (IL)-13 antibody 731.

Prior activation state shapes the microglia response to antihuman TREM2 in a mouse model of Alzheimer's disease.

Triggering receptor expressed on myeloid cells 2 (TREM2) sustains microglia response to brain injury stimuli including apoptotic cells, myelin damage, and amyloid β (Aβ). Alzheimer's disease (AD) risk is associated with the variant, which impairs ligand binding and consequently microglia responses to Aβ pathology. Here, we show that TREM2 engagement by the mAb hT2AB as surrogate ligand activates microglia in 5XFAD transgenic mice that accumulate Aβ and express either the common TREM2 variant () or scRNA-seq of microglia from -5XFAD mice treated once with control hIgG1 exposed four distinct trajectories of microglia activation leading to disease-associated (DAM), interferon-responsive (IFN-R), cycling (Cyc-M), and MHC-II expressing (MHC-II) microglia types.

Interleukin-21 receptor blockade inhibits secondary humoral responses and halts the progression of preestablished disease in the (NZB × NZW)F1 systemic lupus erythematosus model.

Objective: Systemic lupus erythematosus (SLE) is a complex autoimmune disease that is driven in part by chronic B and T lymphocyte hyperresponsiveness to self antigens. A deficiency of interleukin-21 (IL-21) or IL-21 receptor (IL-21R) in mice dramatically reduces inflammation and B and T cell activation in models of autoimmunity, including SLE. However, whether IL-21 is essential for the maintenance and amplification of preestablished inflammation has not been widely examined in various animal models.

Measuring antibody affinities as well as the active concentration of antigens present on a cell surface.

Measuring the affinity of a therapeutic antibody to its antigen, expressed in its native form on a cell surface, is an important aspect to understanding its in vivo potency. Measured affinities can also help in selecting the best antibody for therapy. The on-cell binding affinity of antibodies was determined in the past by labelling the antibody using radioactive, fluorescent, or other probes.