Increase in plasma viral load after oral cholera immunization of HIV-infected subjects.
OBJECTIVE
Constant antigenic stimulation of the large immune cell population contained within gut-associated lymphoid tissue during HIV infection may contribute to patients' total viral load. The aim of this investigation was to evaluate the effect of a mucosal antigenic challenge on HIV replication.


METHODS
Prospective clinical study.


METHODS
Twelve HIV-1-infected men (mean age, 42.3 years) from the Casa de Apoio Santo Antonio, Rio de Janeiro, Brazil, were immunized with combined whole cell-toxin B subunit oral cholera vaccine. Blood was collected on days 0, 2, 4, 6, 10 and 15 after immunization and plasma was tested for cholera toxin-specific antibody response (IgG and IgA), beta2-microglobulin, and plasma viral load. CD4 lymphocyte counts were performed within 1 week before immunization. Five HIV-infected non-immunized individuals were studied as controls.


RESULTS
There were no adverse effects following immunization and no deterioration in clinical outcome during 3 months of follow-up. A transient increase in viral load that ranged from twofold to 60-fold was observed in all cases and was statistically significant on days 2, 6 and 10 (P = 0.017, P = 0.025, P = 0.021, respectively). There was no correlation with CD4 cell counts. None of the non-immunized subjects demonstrated the pattern of viraemia observed after immunization (P > 0.10 on all days).


CONCLUSIONS
Our data indicate that mucosal immunization with oral cholera vaccine induces a transient increase in HIV viraemia, regardless of clinical stage of infection and CD4 cell counts. These findings suggest that mucosal stimulation of HIV-infected patients enhances HIV replication.
Ortigão-de-Sampaio
M B
MB
Departamento de Imunologia, IOC, FIOCRUZ, Rio de Janeiro, Brazil.
Shattock
R J
RJ
Hayes
P
P
Griffin
G E
GE
Linhares-de-Carvalho
M I
MI
Ponce de Leon
A
A
Lewis
D J
DJ
Castello-Branco
L R
LR
D000284:Administration, Oral; D000328:Adult; D000992:Antitoxins / Q000097:blood; D018791:CD4 Lymphocyte Count; D002772:Cholera Toxin / Q000276:immunology; D022121:Cholera Vaccines / Q000008:administration & dosage / Q000276:immunology*; D015658:HIV Infections / Q000276:immunology* / Q000821:virology; D015497:HIV-1 / Q000502:physiology*; D006801:Humans; D018928:Immunity, Mucosal; D007070:Immunoglobulin A / Q000097:blood; D007074:Immunoglobulin G / Q000097:blood; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D019562:Viral Load; D014779:Virus Replication; D001613:beta 2-Microglobulin / Q000032:analysis
D000992:Antitoxins; D022121:Cholera Vaccines; D007070:Immunoglobulin A; D007074:Immunoglobulin G; D001613:beta 2-Microglobulin; D002772:Cholera Toxin