Depletion of lymphocytes, but not neutrophils, via apoptosis in a murine model of Vibrio vulnificus infection.
Vibrio vulnificus causes severe sepsis in humans. There are several reports about the relationship between host immunity and bacterial growth in V. vulnificus infection. However, the effect on leukocytes of V. vulnificus infection in vivo has not been elucidated. A murine model of V. vulnificus infection was used to investigate its effects on leukocytes in this study. Bacteria were recovered from the blood of mice 3 h after subcutaneous injection in the right lower flank. They were detected in 87.5 % (n = 7/8) of mice at 6 h, but this value decreased to 12.5 % (n = 1/8) at 12 h. In contrast, the number of lymphocytes in peripheral blood had already started to decrease at 3 h, and reached a minimum at 6-9 h post-inoculation. Typical DNA laddering, a hallmark of apoptosis, was also detected in thymocytes and splenocytes at 6 and 9 h, and showed a tendency to disappear by 12 h. Although the number of lymphocytes decreased in the model, the numbers of neutrophils did not. These results suggested that V. vulnificus has selective cytotoxicity for lymphocytes in peripheral blood in vivo, and the lymphocyte depletion was probably associated with apoptosis in vivo.
Kashimoto
Takashige
T
Laboratory of Veterinary Public Health1, and Laboratory of Veterinary Anatomy2, School of Veterinary Medicine and Animal Sciences, Kitasato University, Higashi 23-35-1, Towada Aomori 034-8628, Japan 3Department of Molecular Immunology, Research Institute for Microbial Diseases, Osaka University, Osaka 565-0871, Japan.
Ueno
Shunji
S
Laboratory of Veterinary Public Health1, and Laboratory of Veterinary Anatomy2, School of Veterinary Medicine and Animal Sciences, Kitasato University, Higashi 23-35-1, Towada Aomori 034-8628, Japan 3Department of Molecular Immunology, Research Institute for Microbial Diseases, Osaka University, Osaka 565-0871, Japan.
Hayashi
Hisae
H
Laboratory of Veterinary Public Health1, and Laboratory of Veterinary Anatomy2, School of Veterinary Medicine and Animal Sciences, Kitasato University, Higashi 23-35-1, Towada Aomori 034-8628, Japan 3Department of Molecular Immunology, Research Institute for Microbial Diseases, Osaka University, Osaka 565-0871, Japan.
Hanajima
Miyuki
M
Laboratory of Veterinary Public Health1, and Laboratory of Veterinary Anatomy2, School of Veterinary Medicine and Animal Sciences, Kitasato University, Higashi 23-35-1, Towada Aomori 034-8628, Japan 3Department of Molecular Immunology, Research Institute for Microbial Diseases, Osaka University, Osaka 565-0871, Japan.
Yoshioka
Kazuki
K
Laboratory of Veterinary Public Health1, and Laboratory of Veterinary Anatomy2, School of Veterinary Medicine and Animal Sciences, Kitasato University, Higashi 23-35-1, Towada Aomori 034-8628, Japan 3Department of Molecular Immunology, Research Institute for Microbial Diseases, Osaka University, Osaka 565-0871, Japan.
Yoshida
Kenji
K
Laboratory of Veterinary Public Health1, and Laboratory of Veterinary Anatomy2, School of Veterinary Medicine and Animal Sciences, Kitasato University, Higashi 23-35-1, Towada Aomori 034-8628, Japan 3Department of Molecular Immunology, Research Institute for Microbial Diseases, Osaka University, Osaka 565-0871, Japan.
Mutoh
Kenichiro
K
Laboratory of Veterinary Public Health1, and Laboratory of Veterinary Anatomy2, School of Veterinary Medicine and Animal Sciences, Kitasato University, Higashi 23-35-1, Towada Aomori 034-8628, Japan 3Department of Molecular Immunology, Research Institute for Microbial Diseases, Osaka University, Osaka 565-0871, Japan.
Susa
Nobuyuki
N
Laboratory of Veterinary Public Health1, and Laboratory of Veterinary Anatomy2, School of Veterinary Medicine and Animal Sciences, Kitasato University, Higashi 23-35-1, Towada Aomori 034-8628, Japan 3Department of Molecular Immunology, Research Institute for Microbial Diseases, Osaka University, Osaka 565-0871, Japan.
D000818:Animals; D017209:Apoptosis; D053938:DNA Fragmentation; D004195:Disease Models, Animal; D007958:Leukocyte Count; D008070:Lipopolysaccharides / Q000378:metabolism; D018655:Lymphocyte Count; D016131:Lymphocyte Subsets / Q000276:immunology / Q000502:physiology; D008214:Lymphocytes / Q000276:immunology / Q000502:physiology*; D008297:Male; D051379:Mice; D008809:Mice, Inbred C3H; D016513:Mice, SCID; D009504:Neutrophils / Q000276:immunology / Q000502:physiology*; D011956:Receptors, Cell Surface / Q000502:physiology; D015398:Signal Transduction; D013154:Spleen / Q000276:immunology; D013950:Thymus Gland / Q000276:immunology; D051197:Toll-Like Receptor 4; D014735:Vibrio Infections / Q000276:immunology* / Q000382:microbiology; D041261:Vibrio vulnificus / Q000254:growth & development*
D008070:Lipopolysaccharides; D011956:Receptors, Cell Surface; C493487:Tlr4 protein, mouse; D051197:Toll-Like Receptor 4