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Characteristics of memory B cells elicited by a highly efficacious HPV vaccine in subjects with no pre-existing immunity.

Scherer EM, Smith RA, Simonich CA, Niyonzima N, Carter JJ, Galloway DA - PLoS Pathog. (2014)

Bottom Line: These vaccines, like most other prophylactic vaccines, appear to protect by generating antibodies.Here, we have identified and isolated HPV 16-specific memory B cells from female adolescents and young women who received the quadrivalent HPV vaccine in the absence of pre-existing immunity, using fluorescently conjugated HPV 16 pseudoviruses to label antigen receptors on the surface of memory B cells.Antibodies cloned and expressed from these singly sorted HPV 16-pseudovirus labeled memory B cells were predominantly IgG (>IgA>IgM), utilized diverse variable genes, and potently neutralized HPV 16 pseudoviruses in vitro despite possessing only average levels of somatic mutation.

View Article: PubMed Central - PubMed

Affiliation: Human Biology Division, Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America.

ABSTRACT
Licensed human papillomavirus (HPV) vaccines provide near complete protection against the types of HPV that most commonly cause anogenital and oropharyngeal cancers (HPV 16 and 18) when administered to individuals naive to these types. These vaccines, like most other prophylactic vaccines, appear to protect by generating antibodies. However, almost nothing is known about the immunological memory that forms following HPV vaccination, which is required for long-term immunity. Here, we have identified and isolated HPV 16-specific memory B cells from female adolescents and young women who received the quadrivalent HPV vaccine in the absence of pre-existing immunity, using fluorescently conjugated HPV 16 pseudoviruses to label antigen receptors on the surface of memory B cells. Antibodies cloned and expressed from these singly sorted HPV 16-pseudovirus labeled memory B cells were predominantly IgG (>IgA>IgM), utilized diverse variable genes, and potently neutralized HPV 16 pseudoviruses in vitro despite possessing only average levels of somatic mutation. These findings suggest that the quadrivalent HPV vaccine provides an excellent model for studying the development of B cell memory; and, in the context of what is known about memory B cells elicited by influenza vaccination/infection, HIV-1 infection, or tetanus toxoid vaccination, indicates that extensive somatic hypermutation is not required to achieve potent vaccine-specific neutralizing antibody responses.

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HPV 16-specific Bmem represent 0.2% of total Bmem in qHPV vaccinees at month 7.PBMC samples collected at month 7 (n = 12) were enriched for B cells, divided into two parts, and stained with a multicolor flow cytometry panel to identify classic Bmem and either AF488-BPV or AF488-HPV 16. (A) Representative dot plots are shown of the total naive B cell (IgD+CD27−) and Bmem (IgD−CD27+) frequencies in samples collected from subjects EK1006, EK1027, EK1073 and EK1078 (left column), as well as the frequencies of AF488+ Bmem observed by Ag-specific labeling (middle column) or by negative control labeling (right column). Flow cytometry data were first gated for cell size (forward versus side scatter), to exclude doublets and dead cells, and to include B cells (CD3−CD19+) (not shown). (B) AF488-HPV16+ Bmem were observed at a significantly higher frequency than AF488-BPV+ Bmem for all subjects' analyzed (**, p<0.005; paired, two-tailed student's t-test).
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ppat-1004461-g001: HPV 16-specific Bmem represent 0.2% of total Bmem in qHPV vaccinees at month 7.PBMC samples collected at month 7 (n = 12) were enriched for B cells, divided into two parts, and stained with a multicolor flow cytometry panel to identify classic Bmem and either AF488-BPV or AF488-HPV 16. (A) Representative dot plots are shown of the total naive B cell (IgD+CD27−) and Bmem (IgD−CD27+) frequencies in samples collected from subjects EK1006, EK1027, EK1073 and EK1078 (left column), as well as the frequencies of AF488+ Bmem observed by Ag-specific labeling (middle column) or by negative control labeling (right column). Flow cytometry data were first gated for cell size (forward versus side scatter), to exclude doublets and dead cells, and to include B cells (CD3−CD19+) (not shown). (B) AF488-HPV16+ Bmem were observed at a significantly higher frequency than AF488-BPV+ Bmem for all subjects' analyzed (**, p<0.005; paired, two-tailed student's t-test).

Mentions: Representative flow cytometry data for 4 of 12 subjects post-vaccination show that AF488-HPV 16+ Bmem were clearly distinguishable from background, despite having very low cell numbers (only 1–10 cells sorted for each of nine samples; Fig. 1A). In contrast, almost no AF488-BPV+ Bmem were observed. Indeed, a significantly higher frequency of AF488-HPV 16+ Bmem than AF488-BPV+ Bmem were detected in all samples (Fig. 1B), thus confirming that AF488-HPV 16+ Bmem were not simply due to non-specific psV binding. Altogether, HPV 16-specific Bmem comprised ∼0.2% of total Bmem at one-month post-qHPV vaccination, and 29 AF488-HPV 16+ Bmem were singly sorted from nine different subjects' samples.


Characteristics of memory B cells elicited by a highly efficacious HPV vaccine in subjects with no pre-existing immunity.

Scherer EM, Smith RA, Simonich CA, Niyonzima N, Carter JJ, Galloway DA - PLoS Pathog. (2014)

HPV 16-specific Bmem represent 0.2% of total Bmem in qHPV vaccinees at month 7.PBMC samples collected at month 7 (n = 12) were enriched for B cells, divided into two parts, and stained with a multicolor flow cytometry panel to identify classic Bmem and either AF488-BPV or AF488-HPV 16. (A) Representative dot plots are shown of the total naive B cell (IgD+CD27−) and Bmem (IgD−CD27+) frequencies in samples collected from subjects EK1006, EK1027, EK1073 and EK1078 (left column), as well as the frequencies of AF488+ Bmem observed by Ag-specific labeling (middle column) or by negative control labeling (right column). Flow cytometry data were first gated for cell size (forward versus side scatter), to exclude doublets and dead cells, and to include B cells (CD3−CD19+) (not shown). (B) AF488-HPV16+ Bmem were observed at a significantly higher frequency than AF488-BPV+ Bmem for all subjects' analyzed (**, p<0.005; paired, two-tailed student's t-test).
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4199765&req=5

ppat-1004461-g001: HPV 16-specific Bmem represent 0.2% of total Bmem in qHPV vaccinees at month 7.PBMC samples collected at month 7 (n = 12) were enriched for B cells, divided into two parts, and stained with a multicolor flow cytometry panel to identify classic Bmem and either AF488-BPV or AF488-HPV 16. (A) Representative dot plots are shown of the total naive B cell (IgD+CD27−) and Bmem (IgD−CD27+) frequencies in samples collected from subjects EK1006, EK1027, EK1073 and EK1078 (left column), as well as the frequencies of AF488+ Bmem observed by Ag-specific labeling (middle column) or by negative control labeling (right column). Flow cytometry data were first gated for cell size (forward versus side scatter), to exclude doublets and dead cells, and to include B cells (CD3−CD19+) (not shown). (B) AF488-HPV16+ Bmem were observed at a significantly higher frequency than AF488-BPV+ Bmem for all subjects' analyzed (**, p<0.005; paired, two-tailed student's t-test).
Mentions: Representative flow cytometry data for 4 of 12 subjects post-vaccination show that AF488-HPV 16+ Bmem were clearly distinguishable from background, despite having very low cell numbers (only 1–10 cells sorted for each of nine samples; Fig. 1A). In contrast, almost no AF488-BPV+ Bmem were observed. Indeed, a significantly higher frequency of AF488-HPV 16+ Bmem than AF488-BPV+ Bmem were detected in all samples (Fig. 1B), thus confirming that AF488-HPV 16+ Bmem were not simply due to non-specific psV binding. Altogether, HPV 16-specific Bmem comprised ∼0.2% of total Bmem at one-month post-qHPV vaccination, and 29 AF488-HPV 16+ Bmem were singly sorted from nine different subjects' samples.

Bottom Line: These vaccines, like most other prophylactic vaccines, appear to protect by generating antibodies.Here, we have identified and isolated HPV 16-specific memory B cells from female adolescents and young women who received the quadrivalent HPV vaccine in the absence of pre-existing immunity, using fluorescently conjugated HPV 16 pseudoviruses to label antigen receptors on the surface of memory B cells.Antibodies cloned and expressed from these singly sorted HPV 16-pseudovirus labeled memory B cells were predominantly IgG (>IgA>IgM), utilized diverse variable genes, and potently neutralized HPV 16 pseudoviruses in vitro despite possessing only average levels of somatic mutation.

View Article: PubMed Central - PubMed

Affiliation: Human Biology Division, Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America.

ABSTRACT
Licensed human papillomavirus (HPV) vaccines provide near complete protection against the types of HPV that most commonly cause anogenital and oropharyngeal cancers (HPV 16 and 18) when administered to individuals naive to these types. These vaccines, like most other prophylactic vaccines, appear to protect by generating antibodies. However, almost nothing is known about the immunological memory that forms following HPV vaccination, which is required for long-term immunity. Here, we have identified and isolated HPV 16-specific memory B cells from female adolescents and young women who received the quadrivalent HPV vaccine in the absence of pre-existing immunity, using fluorescently conjugated HPV 16 pseudoviruses to label antigen receptors on the surface of memory B cells. Antibodies cloned and expressed from these singly sorted HPV 16-pseudovirus labeled memory B cells were predominantly IgG (>IgA>IgM), utilized diverse variable genes, and potently neutralized HPV 16 pseudoviruses in vitro despite possessing only average levels of somatic mutation. These findings suggest that the quadrivalent HPV vaccine provides an excellent model for studying the development of B cell memory; and, in the context of what is known about memory B cells elicited by influenza vaccination/infection, HIV-1 infection, or tetanus toxoid vaccination, indicates that extensive somatic hypermutation is not required to achieve potent vaccine-specific neutralizing antibody responses.

Show MeSH
Related in: MedlinePlus