Development of human cytomegalovirus-specific T cell immunity during primary infection of pregnant women and its correlation with virus transmission to the fetus.
OBJECTIVE
We sought to study the development of human cytomegalovirus (HCMV)-specific T cell-mediated immune responses during primary HCMV infection in pregnancy.


METHODS
The HCMV-specific lymphoproliferative response (LPR) and intracellular cytokine (interferon [IFN]- gamma and interleukin [IL]-2) production were investigated during the first year after primary infection in 49 pregnant women and 9 nonpregnant control subjects. An HCMV-specific CD4(+) and CD8(+) T cell LPR was detected by the 5,6-carboxyfluorescein diacetate succinimidyl ester dilution method, and a cell-division index was calculated.


RESULTS
The CD4(+) T cell LPR developed slightly earlier than the CD8(+) T cell LPR. However, CDI values for both T cell subpopulations were lower than those of seropositive control subjects in both pregnant and nonpregnant individuals. During the first month after infection, IFN- gamma -producing CD4(+) and CD8(+) T cells were consistently observed, whereas IL-2-producing T cells were very rarely detected in blood. A correlation between the development of HCMV-specific LPR and virus clearance from blood was observed. A significantly delayed development of the CD4(+) T cell LPR was observed in infected mothers who transmitted virus to the fetus, compared with those who did not.


CONCLUSIONS
The development of adaptive T cell immunity after primary HCMV infection appears to be a complex and slow process until a memory T cell response develops. The T cell immune response appears to influence vertical HCMV transmission.
Lilleri
Daniele
D
Servizio di Virologia, Fondazione Istituto di Ricovero e Cura a Carattere Scientifico, Policlinico San Matteo, Pavia, Italy.
Fornara
Chiara
C
Furione
Milena
M
Zavattoni
Maurizio
M
Revello
Maria Grazia
MG
Gerna
Giuseppe
G
D000293:Adolescent; D000328:Adult; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology; D016022:Case-Control Studies; D003587:Cytomegalovirus / Q000276:immunology*; D003586:Cytomegalovirus Infections / Q000276:immunology / Q000635:transmission*; D005260:Female; D005434:Flow Cytometry; D006801:Humans; D007231:Infant, Newborn; D018445:Infectious Disease Transmission, Vertical; D007371:Interferon-gamma / Q000032:analysis; D007376:Interleukin-2 / Q000032:analysis; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious / Q000276:immunology*
D007376:Interleukin-2; D007371:Interferon-gamma