Immunization with class I human histocompatibility leukocyte antigen can protect macaques against challenge infection with SIVmac-32H.
OBJECTIVE
To evaluate the efficacy of immunopurified class I human histocompatibility leukocyte antigen (HLA) to protect against SIV infection.


METHODS
HLA class I antigens were immunopurified from a human B-lymphoblastoid cell line. Groups of four macaques were vaccinated subcutaneously with four doses of the immunogen in adjuvant, or with adjuvant alone and subsequently challenged intravenously with 10 median monkey infectious doses of cell-free SIVmac-32H. Infection was determined by polymerase chain reaction for SIVmac proviral DNA and by virus isolation. Antigen-specific humoral and cellular immune responses were monitored.


RESULTS
Macaques immunized with the HLA molecules produced anti-HLA class I antibodies that inhibited SIV replication in vitro and downregulated autologous T-cell proliferation against irradiated C8166 cells. They were partially protected (two out of four) from virus infection for at least 33 weeks when challenged with SIV grown in human cells. All four control animals were infected.


CONCLUSIONS
This demonstration of partial protection, together with our previous work reporting that vaccination with allogenic cynomolgus lymphocytes can protect against challenge infection with SIV grown in simian cells, suggests that allogenic immune response induced before or during establishment of HIV infection may have important implications for AIDS disease progression.
Chan
W L
WL
National Institute for Biological Standards and Control, South Mimms, Potters Bar, UK.
Rodgers
A
A
Grief
C
C
Almond
N
N
Ellis
S
S
Flanagan
B
B
Silvera
P
P
Bootman
J
J
Stott
J
J
Kent
K
K
D000818:Animals; D000914:Antibodies, Viral / Q000096:biosynthesis; D015536:Down-Regulation; D015395:Histocompatibility Antigens Class I / Q000032:analysis / Q000276:immunology* / Q000302:isolation & purification; D006801:Humans; D007111:Immunity, Cellular; D008213:Lymphocyte Activation; D008252:Macaca fascicularis; D016097:Simian Acquired Immunodeficiency Syndrome / Q000517:prevention & control*; D015302:Simian Immunodeficiency Virus / Q000276:immunology / Q000502:physiology; D013601:T-Lymphocytes / Q000276:immunology; D014611:Vaccination; D014771:Virion / Q000737:chemistry; D014779:Virus Replication
D000914:Antibodies, Viral; D015395:Histocompatibility Antigens Class I