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Neutrophil recruitment to lymph nodes limits local humoral response to Staphylococcus aureus.

Kamenyeva O, Boularan C, Kabat J, Cheung GY, Cicala C, Yeh AJ, Chan JL, Periasamy S, Otto M, Kehrl JH - PLoS Pathog. (2015)

Bottom Line: They are rapidly mobilized to sites of infection where they help marshal host defenses and remove bacteria by phagocytosis.Within lymph nodes neutrophils infiltrate the medulla and interfollicular areas, but avoid crossing follicle borders.Our data reveal that neutrophils mobilized from the bone marrow in response to a local bacterial challenge dampen the early humoral response in the lymph node.

View Article: PubMed Central - PubMed

Affiliation: B-Cell Molecular Immunology Section, Laboratory of Immunoregulation, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, United States of America.

ABSTRACT
Neutrophils form the first line of host defense against bacterial pathogens. They are rapidly mobilized to sites of infection where they help marshal host defenses and remove bacteria by phagocytosis. While splenic neutrophils promote marginal zone B cell antibody production in response to administered T cell independent antigens, whether neutrophils shape humoral immunity in other lymphoid organs is controversial. Here we investigate the neutrophil influx following the local injection of Staphylococcus aureus adjacent to the inguinal lymph node and determine neutrophil impact on the lymph node humoral response. Using intravital microscopy we show that local immunization or infection recruits neutrophils from the blood to lymph nodes in waves. The second wave occurs temporally with neutrophils mobilized from the bone marrow. Within lymph nodes neutrophils infiltrate the medulla and interfollicular areas, but avoid crossing follicle borders. In vivo neutrophils form transient and long-lived interactions with B cells and plasma cells, and their depletion augments production of antigen-specific IgG and IgM in the lymph node. In vitro activated neutrophils establish synapse- and nanotube-like interactions with B cells and reduce B cell IgM production in a TGF-β1 dependent manner. Our data reveal that neutrophils mobilized from the bone marrow in response to a local bacterial challenge dampen the early humoral response in the lymph node.

No MeSH data available.


Related in: MedlinePlus

BM neutrophils are mobilized to the blood stream after local immunization.LysM-GFP mice were injected with S. aureus bioparticles near the iLN. Neutrophil mobilization was analyzed using flow cytometry of the whole blood or TP-LSM of the calvarium bone marrow. Anti VE-cadherin antibody or EB were injected intravenously to outline the blood vessels. (A) Flow cytometry plots of GFPhi cells in the blood of mice injected subcutaneously with PBS, intravenously with KC+AMD3100, or subcutaneously with S. aureus are shown. Results are from 0–2 h after injection and representative of 3 independent experiments. (B) Kinetics of neutrophil recruitment in mice injected with opsonized (Ops) or non-opsonized (Non-ops) S. aureus versus KC+AMD3100 between 0 and 3 h. Data are from flow cytometry analysis of whole blood. N = 3; repeated 3 times. Means ± SEM. (C) TP-LSM images of calvarium capillaries (Alexa Fluor 660-conjugated anti-VE-cadherin, red) at 2 h after immunization (left) or PBS injection (right). GFPhi cells (green) within the niche (blue arrows) and within the blood vessels (white arrows) are indicated. Scale bars: 30 μm. (D) Images of the central vein in S. aureus (left) and PBS (right) injected mice 3 h later (S1 Movie). Central vein and vascular niche (EB, red) borders are shown with dashed lines. Scale bars: 50 μm. Images are representative of 5 imaging sessions.
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ppat.1004827.g007: BM neutrophils are mobilized to the blood stream after local immunization.LysM-GFP mice were injected with S. aureus bioparticles near the iLN. Neutrophil mobilization was analyzed using flow cytometry of the whole blood or TP-LSM of the calvarium bone marrow. Anti VE-cadherin antibody or EB were injected intravenously to outline the blood vessels. (A) Flow cytometry plots of GFPhi cells in the blood of mice injected subcutaneously with PBS, intravenously with KC+AMD3100, or subcutaneously with S. aureus are shown. Results are from 0–2 h after injection and representative of 3 independent experiments. (B) Kinetics of neutrophil recruitment in mice injected with opsonized (Ops) or non-opsonized (Non-ops) S. aureus versus KC+AMD3100 between 0 and 3 h. Data are from flow cytometry analysis of whole blood. N = 3; repeated 3 times. Means ± SEM. (C) TP-LSM images of calvarium capillaries (Alexa Fluor 660-conjugated anti-VE-cadherin, red) at 2 h after immunization (left) or PBS injection (right). GFPhi cells (green) within the niche (blue arrows) and within the blood vessels (white arrows) are indicated. Scale bars: 30 μm. (D) Images of the central vein in S. aureus (left) and PBS (right) injected mice 3 h later (S1 Movie). Central vein and vascular niche (EB, red) borders are shown with dashed lines. Scale bars: 50 μm. Images are representative of 5 imaging sessions.

Mentions: To analyze kinetics of neutrophil recruitment from the BM to the blood in response to a local immunization, we compared the recruitment rates after subcutaneous injection of S. aureus to those after intravenous KC/AMD3100 injections. Flow cytometry analysis of whole blood revealed a 4-fold increase of the GFPhi cell population in S. aureus and 10-fold increase in KC+AMD3100 injected mice 2 h after injection (Fig 7A), while neutrophil numbers in the blood of PBS injected control remained at a baseline level. Importantly, neutrophil recruitment to KC+AMD3100 reached plateau 1 h after injection, while peak of neutrophil recruitment after S. aureus injection was observed between 3 and 4 h after injection (Fig 7B). Furthermore, we found a 3-fold increase in neutrophil recruitment rate in mice injected with opsonized S. aureus bioparticles comparing to mice injected with non-opsonized bacteria (Fig 7B).


Neutrophil recruitment to lymph nodes limits local humoral response to Staphylococcus aureus.

Kamenyeva O, Boularan C, Kabat J, Cheung GY, Cicala C, Yeh AJ, Chan JL, Periasamy S, Otto M, Kehrl JH - PLoS Pathog. (2015)

BM neutrophils are mobilized to the blood stream after local immunization.LysM-GFP mice were injected with S. aureus bioparticles near the iLN. Neutrophil mobilization was analyzed using flow cytometry of the whole blood or TP-LSM of the calvarium bone marrow. Anti VE-cadherin antibody or EB were injected intravenously to outline the blood vessels. (A) Flow cytometry plots of GFPhi cells in the blood of mice injected subcutaneously with PBS, intravenously with KC+AMD3100, or subcutaneously with S. aureus are shown. Results are from 0–2 h after injection and representative of 3 independent experiments. (B) Kinetics of neutrophil recruitment in mice injected with opsonized (Ops) or non-opsonized (Non-ops) S. aureus versus KC+AMD3100 between 0 and 3 h. Data are from flow cytometry analysis of whole blood. N = 3; repeated 3 times. Means ± SEM. (C) TP-LSM images of calvarium capillaries (Alexa Fluor 660-conjugated anti-VE-cadherin, red) at 2 h after immunization (left) or PBS injection (right). GFPhi cells (green) within the niche (blue arrows) and within the blood vessels (white arrows) are indicated. Scale bars: 30 μm. (D) Images of the central vein in S. aureus (left) and PBS (right) injected mice 3 h later (S1 Movie). Central vein and vascular niche (EB, red) borders are shown with dashed lines. Scale bars: 50 μm. Images are representative of 5 imaging sessions.
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Related In: Results  -  Collection

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ppat.1004827.g007: BM neutrophils are mobilized to the blood stream after local immunization.LysM-GFP mice were injected with S. aureus bioparticles near the iLN. Neutrophil mobilization was analyzed using flow cytometry of the whole blood or TP-LSM of the calvarium bone marrow. Anti VE-cadherin antibody or EB were injected intravenously to outline the blood vessels. (A) Flow cytometry plots of GFPhi cells in the blood of mice injected subcutaneously with PBS, intravenously with KC+AMD3100, or subcutaneously with S. aureus are shown. Results are from 0–2 h after injection and representative of 3 independent experiments. (B) Kinetics of neutrophil recruitment in mice injected with opsonized (Ops) or non-opsonized (Non-ops) S. aureus versus KC+AMD3100 between 0 and 3 h. Data are from flow cytometry analysis of whole blood. N = 3; repeated 3 times. Means ± SEM. (C) TP-LSM images of calvarium capillaries (Alexa Fluor 660-conjugated anti-VE-cadherin, red) at 2 h after immunization (left) or PBS injection (right). GFPhi cells (green) within the niche (blue arrows) and within the blood vessels (white arrows) are indicated. Scale bars: 30 μm. (D) Images of the central vein in S. aureus (left) and PBS (right) injected mice 3 h later (S1 Movie). Central vein and vascular niche (EB, red) borders are shown with dashed lines. Scale bars: 50 μm. Images are representative of 5 imaging sessions.
Mentions: To analyze kinetics of neutrophil recruitment from the BM to the blood in response to a local immunization, we compared the recruitment rates after subcutaneous injection of S. aureus to those after intravenous KC/AMD3100 injections. Flow cytometry analysis of whole blood revealed a 4-fold increase of the GFPhi cell population in S. aureus and 10-fold increase in KC+AMD3100 injected mice 2 h after injection (Fig 7A), while neutrophil numbers in the blood of PBS injected control remained at a baseline level. Importantly, neutrophil recruitment to KC+AMD3100 reached plateau 1 h after injection, while peak of neutrophil recruitment after S. aureus injection was observed between 3 and 4 h after injection (Fig 7B). Furthermore, we found a 3-fold increase in neutrophil recruitment rate in mice injected with opsonized S. aureus bioparticles comparing to mice injected with non-opsonized bacteria (Fig 7B).

Bottom Line: They are rapidly mobilized to sites of infection where they help marshal host defenses and remove bacteria by phagocytosis.Within lymph nodes neutrophils infiltrate the medulla and interfollicular areas, but avoid crossing follicle borders.Our data reveal that neutrophils mobilized from the bone marrow in response to a local bacterial challenge dampen the early humoral response in the lymph node.

View Article: PubMed Central - PubMed

Affiliation: B-Cell Molecular Immunology Section, Laboratory of Immunoregulation, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, United States of America.

ABSTRACT
Neutrophils form the first line of host defense against bacterial pathogens. They are rapidly mobilized to sites of infection where they help marshal host defenses and remove bacteria by phagocytosis. While splenic neutrophils promote marginal zone B cell antibody production in response to administered T cell independent antigens, whether neutrophils shape humoral immunity in other lymphoid organs is controversial. Here we investigate the neutrophil influx following the local injection of Staphylococcus aureus adjacent to the inguinal lymph node and determine neutrophil impact on the lymph node humoral response. Using intravital microscopy we show that local immunization or infection recruits neutrophils from the blood to lymph nodes in waves. The second wave occurs temporally with neutrophils mobilized from the bone marrow. Within lymph nodes neutrophils infiltrate the medulla and interfollicular areas, but avoid crossing follicle borders. In vivo neutrophils form transient and long-lived interactions with B cells and plasma cells, and their depletion augments production of antigen-specific IgG and IgM in the lymph node. In vitro activated neutrophils establish synapse- and nanotube-like interactions with B cells and reduce B cell IgM production in a TGF-β1 dependent manner. Our data reveal that neutrophils mobilized from the bone marrow in response to a local bacterial challenge dampen the early humoral response in the lymph node.

No MeSH data available.


Related in: MedlinePlus