title: CRISPR-Mediated Slamf1Δ/Δ Slamf5Δ/Δ Slamf6Δ/Δ Triple Gene Disruption Reveals NKT Cell Defects but Not T Follicular Helper Cell Defects.
abstract: SAP (SH2D1A) is required intrinsically in CD4 T cells to generate germinal center responses and long-term humoral immunity. SAP binds to SLAM family receptors, including SLAM, CD84, and Ly108 to enhance cytokine secretion and sustained T cell:B cell adhesion, which both improve T follicular helper (Tfh) cell aid to germinal center (GC) B cells. To understand the overlapping roles of multiple SLAM family receptors in germinal center responses, Slamf1Δ/Δ Slamf5Δ/Δ Slamf6Δ/Δ triple gene disruption (Slamf1,5,6Δ/Δ) mice were generated using CRISPR-Cas9 gene editing to eliminate expression of SLAM (CD150), CD84, and Ly108, respectively. Gene targeting was highly efficient, with 6 of 6 alleles disrupted in 14 of 23 pups and the majority of alleles disrupted in the remaining pups. NKT cell differentiation in Slamf1,5,6Δ/Δ mice was defective, but not completely absent. The remaining NKT cells exhibited substantially increased 2B4 (SLAMF4) expression. Surprisingly, there were no overt defects in germinal center responses to acute viral infections or protein immunizations in Slamf1,5,6Δ/Δ mice, unlike Sh2d1a-/- mice. Similarly, in the context of a competitive environment, SLAM family receptor expressing GC Tfh cell, GC B cell, and plasma cell responses exhibited no advantages over Slamf1,5,6Δ/Δ cells.
authors.affiliation: Division of Vaccine Discovery, La Jolla Institute for Allergy and Immunology, La Jolla, California, United States of America.
authors.forename: Joyce K
authors.initials: JK
authors.lastname: Hu
authors.affiliation: Division of Vaccine Discovery, La Jolla Institute for Allergy and Immunology, La Jolla, California, United States of America.
authors.forename: Jordan C
authors.initials: JC
authors.lastname: Crampton
authors.affiliation: Division of Vaccine Discovery, La Jolla Institute for Allergy and Immunology, La Jolla, California, United States of America.
authors.forename: Michela
authors.initials: M
authors.lastname: Locci
authors.affiliation: Division of Vaccine Discovery, La Jolla Institute for Allergy and Immunology, La Jolla, California, United States of America.|Department of Medicine, University of California, San Diego School of Medicine, La Jolla, California, United States of America.
authors.forename: Shane
authors.initials: S
authors.lastname: Crotty
mesh_terms: D000818:Animals; D064112:Clustered Regularly Interspaced Short Palindromic Repeats; D000072669:Gene Editing; D055785:Gene Knockdown Techniques; D051379:Mice; D055611:Natural Killer T-Cells / Q000276:immunology*; D010950:Plasma Cells / Q000276:immunology*; D000071176:Signaling Lymphocytic Activation Molecule Family / Q000235:genetics / Q000276:immunology*; D000071177:Signaling Lymphocytic Activation Molecule Family Member 1 / Q000235:genetics / Q000276:immunology*; D006377:T-Lymphocytes, Helper-Inducer / Q000276:immunology*
chemical_list: C490007:Cd244a protein, mouse; C498971:Cd84 protein, mouse; D000071176:Signaling Lymphocytic Activation Molecule Family; C000604062:Slamf1 protein, mouse; C000604063:Slamf6 protein, mouse; D000071177:Signaling Lymphocytic Activation Molecule Family Member 1