We already have antibodies in our lungs if we have experienced enough vaxxed shedding people. When it comes to the viruses - There are no SARS-CoV-2 viruses with the toxic spike protein in circulation anymore as the omicron variants out-competed Delta. Viruses can't replicate in healthy tissue, but while the spike protein is toxic for everyone you can get immune or resistant to snake venom, bee stings and other toxic proteins thanks to antibodies. The immune response to coronaviruses are mostly not about antibodies, and generally most coronaviruses infect your gut bacteria, who are operating separately from your immune system. You breathe the coronavirus in, it goes to your blood, but only cause havoc in the gut if you're healthy.