Donor 1 and 2: primary CD4+ T cells were activated using 10 µl of ImmunoCult Human CD3–CD28 T cell activator (StemCell Technologies) per milliliter of medium. After 3 d, 1 million cells were electroporated with 3 µl of Cas9–RNPs using Nucleocuvette strips in an Amaxa 4D-Nucleofector System X unit (P3 solution, program EO-115). Six days later, cells were re-activated using 2.5 µl of ImmunoCult reagent per milliliter of medium and cultured for three additional days prior to use in downstream assays including HIV challenge; For donors 3 and 4, primary CD4+ T cells were activated for 2 d with 5 µg/ml soluble anti-CD28 (Tonbo Biosceiences) on plates that were coated overnight with 10 µg/ml anti-CD3 (Tonbo Biosciences). Cells were electroporated with Cas9–RNPs as described above, except with 300,000 cells per condition.