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Role of humoral versus cellular responses induced by a protective dengue vaccine candidate.

Zellweger RM, Miller R, Eddy WE, White LJ, Johnston RE, Shresta S - PLoS Pathog. (2013)

Bottom Line: Severe dengue disease is associated with sub-protective levels of antibody, which exacerbate disease upon re-infection.A dengue vaccine should generate protective immunity without increasing severity of disease.This study explores the immunological basis of protection induced by a dengue vaccine and suggests that a safe and efficient vaccine against dengue should trigger both arms of the immune system.

View Article: PubMed Central - PubMed

Affiliation: La Jolla Institute for Allergy & Immunology, La Jolla, California, United States of America.

ABSTRACT
With 2.5 billion people at risk, dengue is a major emerging disease threat and an escalating public health problem worldwide. Dengue virus causes disease ranging from a self-limiting febrile illness (dengue fever) to the potentially fatal dengue hemorrhagic fever/dengue shock syndrome. Severe dengue disease is associated with sub-protective levels of antibody, which exacerbate disease upon re-infection. A dengue vaccine should generate protective immunity without increasing severity of disease. To date, the determinants of vaccine-mediated protection against dengue remain unclear, and additional correlates of protection are urgently needed. Here, mice were immunized with viral replicon particles expressing the dengue envelope protein ectodomain to assess the relative contribution of humoral versus cellular immunity to protection. Vaccination with viral replicon particles provided robust protection against dengue challenge. Vaccine-induced humoral responses had the potential to either protect from or exacerbate dengue disease upon challenge, whereas cellular immune responses were beneficial. This study explores the immunological basis of protection induced by a dengue vaccine and suggests that a safe and efficient vaccine against dengue should trigger both arms of the immune system.

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Related in: MedlinePlus

Passive transfer of DENV2 E85-VRP-immune serum or adoptive transfer of DENV2 E85-VRP-immune B cells can increase the viral RNA levels in the liver upon infection with DENV.(A) 50, 200 or 500 µl DENV2 E85-VRP-immune serum (from AG129 mice immunized i.p. 14 and 5 days prior to serum collection) were transferred i.v. into naïve AG129 recipient mice one day prior to challenge with 5×108 GE DENV. One group received 500 µl of VRP immune serum i.v. 3, 2 and 1 day before challenge (total 1.5 ml). One control group received 1.5 ml naïve serum (500 µl 3, 2 and 1 day prior to challenge), another control group received no serum and was infected in the presence of anti-DENV Ab (ADE) and the last control group received no serum and was infected in the presence of an isotype control Ab of irrelevant specificity (baseline). Viral RNA was quantified in the liver by qRT-PCR 3 days after challenge. (B) 2×107 DENV2 E85-VRP-primed splenic B cells (from AG129 mice immunized i.p. 14 and 5 days prior to B-cell isolation) were transferred i.v. into naïve AG129 recipient mice one day prior to challenge with 5×108 GE DENV. The “baseline” and “ADE” control groups were included as in A. Each symbol depicts one mouse, P-values from two-tailed unpaired t-test with Welch's correction, confidence interval 95%, * P≤0.05, ** P≤0.01, *** P≤0.001.
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ppat-1003723-g003: Passive transfer of DENV2 E85-VRP-immune serum or adoptive transfer of DENV2 E85-VRP-immune B cells can increase the viral RNA levels in the liver upon infection with DENV.(A) 50, 200 or 500 µl DENV2 E85-VRP-immune serum (from AG129 mice immunized i.p. 14 and 5 days prior to serum collection) were transferred i.v. into naïve AG129 recipient mice one day prior to challenge with 5×108 GE DENV. One group received 500 µl of VRP immune serum i.v. 3, 2 and 1 day before challenge (total 1.5 ml). One control group received 1.5 ml naïve serum (500 µl 3, 2 and 1 day prior to challenge), another control group received no serum and was infected in the presence of anti-DENV Ab (ADE) and the last control group received no serum and was infected in the presence of an isotype control Ab of irrelevant specificity (baseline). Viral RNA was quantified in the liver by qRT-PCR 3 days after challenge. (B) 2×107 DENV2 E85-VRP-primed splenic B cells (from AG129 mice immunized i.p. 14 and 5 days prior to B-cell isolation) were transferred i.v. into naïve AG129 recipient mice one day prior to challenge with 5×108 GE DENV. The “baseline” and “ADE” control groups were included as in A. Each symbol depicts one mouse, P-values from two-tailed unpaired t-test with Welch's correction, confidence interval 95%, * P≤0.05, ** P≤0.01, *** P≤0.001.

Mentions: To assess whether the protective effect of the DENV2 E85-VRP immunization was mediated by serum, 50 µl, 200 µl or 500 µl of serum from AG129 mice immunized 14 and 5 days earlier with 1×106 IU of DENV2 E85-VRP were injected i.v. into naïve AG129 recipient mice one day prior to challenge with 5×108 GE DENV. An additional group of recipients received a total of 1500 µl of DENV2 E85-VRP-immune serum i.v. (500 µl on day -3, -2 and -1). As controls, one group received 1500 µl naïve serum (500 µl on day -3, -2, -1) and two groups received no serum and were challenged either in the absence or presence of exogenous anti-DENV Ab (baseline and ADE groups). Viral RNA was quantified in the liver 3 days after challenge (figure 3A). Viral RNA levels in the liver were significantly higher in all groups that had received DENV2 E85-VRP-immune serum compared to the baseline group. As transfer of naïve serum had no effect on the viral load, we concluded that Ab present in the serum of immunized mice had caused ADE. To confirm these results, 2×107 B cells from AG129 mice immunized with DENV2 E85-VRP 14 and 5 days earlier were adoptively transferred into naïve AG129 recipients one day prior to challenge with DENV. Similar to the ADE control animals, the mice that received DENV2 E85-VRP-primed B cells prior to challenge had viral RNA levels in the liver 3 days after challenge that were significantly higher than baseline (figure 3B). Taken together, these experiments have revealed that although immunization with DENV2 E85-VRP was protective, the presence of either serum or B cells from DENV2 E85-VRP-immunized mice did not reduce viral load upon challenge with DENV, but instead increased viral loads in the liver.


Role of humoral versus cellular responses induced by a protective dengue vaccine candidate.

Zellweger RM, Miller R, Eddy WE, White LJ, Johnston RE, Shresta S - PLoS Pathog. (2013)

Passive transfer of DENV2 E85-VRP-immune serum or adoptive transfer of DENV2 E85-VRP-immune B cells can increase the viral RNA levels in the liver upon infection with DENV.(A) 50, 200 or 500 µl DENV2 E85-VRP-immune serum (from AG129 mice immunized i.p. 14 and 5 days prior to serum collection) were transferred i.v. into naïve AG129 recipient mice one day prior to challenge with 5×108 GE DENV. One group received 500 µl of VRP immune serum i.v. 3, 2 and 1 day before challenge (total 1.5 ml). One control group received 1.5 ml naïve serum (500 µl 3, 2 and 1 day prior to challenge), another control group received no serum and was infected in the presence of anti-DENV Ab (ADE) and the last control group received no serum and was infected in the presence of an isotype control Ab of irrelevant specificity (baseline). Viral RNA was quantified in the liver by qRT-PCR 3 days after challenge. (B) 2×107 DENV2 E85-VRP-primed splenic B cells (from AG129 mice immunized i.p. 14 and 5 days prior to B-cell isolation) were transferred i.v. into naïve AG129 recipient mice one day prior to challenge with 5×108 GE DENV. The “baseline” and “ADE” control groups were included as in A. Each symbol depicts one mouse, P-values from two-tailed unpaired t-test with Welch's correction, confidence interval 95%, * P≤0.05, ** P≤0.01, *** P≤0.001.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC3814346&req=5

ppat-1003723-g003: Passive transfer of DENV2 E85-VRP-immune serum or adoptive transfer of DENV2 E85-VRP-immune B cells can increase the viral RNA levels in the liver upon infection with DENV.(A) 50, 200 or 500 µl DENV2 E85-VRP-immune serum (from AG129 mice immunized i.p. 14 and 5 days prior to serum collection) were transferred i.v. into naïve AG129 recipient mice one day prior to challenge with 5×108 GE DENV. One group received 500 µl of VRP immune serum i.v. 3, 2 and 1 day before challenge (total 1.5 ml). One control group received 1.5 ml naïve serum (500 µl 3, 2 and 1 day prior to challenge), another control group received no serum and was infected in the presence of anti-DENV Ab (ADE) and the last control group received no serum and was infected in the presence of an isotype control Ab of irrelevant specificity (baseline). Viral RNA was quantified in the liver by qRT-PCR 3 days after challenge. (B) 2×107 DENV2 E85-VRP-primed splenic B cells (from AG129 mice immunized i.p. 14 and 5 days prior to B-cell isolation) were transferred i.v. into naïve AG129 recipient mice one day prior to challenge with 5×108 GE DENV. The “baseline” and “ADE” control groups were included as in A. Each symbol depicts one mouse, P-values from two-tailed unpaired t-test with Welch's correction, confidence interval 95%, * P≤0.05, ** P≤0.01, *** P≤0.001.
Mentions: To assess whether the protective effect of the DENV2 E85-VRP immunization was mediated by serum, 50 µl, 200 µl or 500 µl of serum from AG129 mice immunized 14 and 5 days earlier with 1×106 IU of DENV2 E85-VRP were injected i.v. into naïve AG129 recipient mice one day prior to challenge with 5×108 GE DENV. An additional group of recipients received a total of 1500 µl of DENV2 E85-VRP-immune serum i.v. (500 µl on day -3, -2 and -1). As controls, one group received 1500 µl naïve serum (500 µl on day -3, -2, -1) and two groups received no serum and were challenged either in the absence or presence of exogenous anti-DENV Ab (baseline and ADE groups). Viral RNA was quantified in the liver 3 days after challenge (figure 3A). Viral RNA levels in the liver were significantly higher in all groups that had received DENV2 E85-VRP-immune serum compared to the baseline group. As transfer of naïve serum had no effect on the viral load, we concluded that Ab present in the serum of immunized mice had caused ADE. To confirm these results, 2×107 B cells from AG129 mice immunized with DENV2 E85-VRP 14 and 5 days earlier were adoptively transferred into naïve AG129 recipients one day prior to challenge with DENV. Similar to the ADE control animals, the mice that received DENV2 E85-VRP-primed B cells prior to challenge had viral RNA levels in the liver 3 days after challenge that were significantly higher than baseline (figure 3B). Taken together, these experiments have revealed that although immunization with DENV2 E85-VRP was protective, the presence of either serum or B cells from DENV2 E85-VRP-immunized mice did not reduce viral load upon challenge with DENV, but instead increased viral loads in the liver.

Bottom Line: Severe dengue disease is associated with sub-protective levels of antibody, which exacerbate disease upon re-infection.A dengue vaccine should generate protective immunity without increasing severity of disease.This study explores the immunological basis of protection induced by a dengue vaccine and suggests that a safe and efficient vaccine against dengue should trigger both arms of the immune system.

View Article: PubMed Central - PubMed

Affiliation: La Jolla Institute for Allergy & Immunology, La Jolla, California, United States of America.

ABSTRACT
With 2.5 billion people at risk, dengue is a major emerging disease threat and an escalating public health problem worldwide. Dengue virus causes disease ranging from a self-limiting febrile illness (dengue fever) to the potentially fatal dengue hemorrhagic fever/dengue shock syndrome. Severe dengue disease is associated with sub-protective levels of antibody, which exacerbate disease upon re-infection. A dengue vaccine should generate protective immunity without increasing severity of disease. To date, the determinants of vaccine-mediated protection against dengue remain unclear, and additional correlates of protection are urgently needed. Here, mice were immunized with viral replicon particles expressing the dengue envelope protein ectodomain to assess the relative contribution of humoral versus cellular immunity to protection. Vaccination with viral replicon particles provided robust protection against dengue challenge. Vaccine-induced humoral responses had the potential to either protect from or exacerbate dengue disease upon challenge, whereas cellular immune responses were beneficial. This study explores the immunological basis of protection induced by a dengue vaccine and suggests that a safe and efficient vaccine against dengue should trigger both arms of the immune system.

Show MeSH
Related in: MedlinePlus