HIV-1 16055 NFL delta Gly4 Trimer Vaccine(National Institute of Allergy & Infectious Diseases)

The goal of this clinical trial is to test 16055 NFL delta Gly4 Env protein trimer and Trimer 4571 combined with 3M-052-AF + Alum adjuvant and Ad4-Env145NFL viral particles as heterologous prime-boost regimens in adult participants without HIV.
The main question[s] it aims to answer are:
* Are these vaccine regimens safe and well tolerated?
* Are the prime-boost vaccine regimens that include Ad4-Env145NFL and Trimer 4571 as heterologous boosts going contribute to the development of B-cell and antibody responses?
Participants will attend scheduled study visits to receive their vaccine and will record symptoms on a daily eDiary.