In recent decades, the treatment of autoimmune diseases has moved from the use of hormones and conventional immunosuppressive drugs to biological agents. B cell proliferation and maturation play crucial roles in the development of autoimmune diseases. The tumor necrosis factor superfamily ligand B cell activating factor (BAFF) and its receptor mediate B cell survival through regulating signaling pathways. Therefore, BAFF and its receptors are important therapeutic targets for the treatment of autoimmune diseases. This review describes the mechanism of BAFF and its receptor in the human body system and introduces the latest views on how over-activation of BAFF pathway promotes the development of autoimmune diseases including systemic lupus erythematosus, Sjogren's syndrome, and rheumatoid arthritis. In connection to the treatment of the above three diseases, this review discusses the clinical trials and application status of three BAFF-targeting antibody drugs, including Belimumab, Tabalumab and Atacicept. Finally, this review proposes new strategies that targeting the BAFF pathway to provide a new treatment for autoimmune diseases.
Autoimmune Diseases/drug therapy* ; B-Cell Activating Factor/therapeutic use* ; B-Lymphocytes ; Humans ; Interleukin-4 ; Lupus Erythematosus, Systemic/drug therapy*

Coronavirus disease (COVID-19) is an infectious disease caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), with strong contagiousness, high susceptibility and long incubation period. cell entry by SARS-CoV-2 requires the binding between the receptor-binding domain of the viral spike protein and the cellular angiotensin-converting enzyme 2 (ACE2). Here, we briefly reviewed the mechanisms underlying the interaction between SARS-CoV-2 and ACE2, and summarized the latest research progress on SARS-CoV-2 neutralizing monoclonal antibodies and nanobodies, so as to better understand the development process and drug research direction of COVID-19. This review may facilitate understanding the development of neutralizing antibody drugs for emerging infectious diseases, especially for COVID-19.
Angiotensin-Converting Enzyme 2 ; Antibodies, Monoclonal ; Antibodies, Neutralizing ; Antibodies, Viral ; COVID-19 ; Humans ; Peptidyl-Dipeptidase A/metabolism* ; Protein Binding ; SARS-CoV-2 ; Single-Domain Antibodies ; Spike Glycoprotein, Coronavirus/metabolism*

Adult ; Antibodies, Viral/isolation & purification* ; COVID-19/virology* ; Feces/chemistry* ; Female ; Humans ; Intestines/virology* ; Male ; RNA, Ribosomal, 16S/genetics* ; RNA, Viral/isolation & purification* ; SARS-CoV-2/pathogenicity*

Animals ; SARS-CoV-2 ; Antibodies, Neutralizing ; Macaca mulatta ; COVID-19/prevention & control* ; Antibodies, Viral ; Vaccines