INFECTION AND IMMUNITY, Mar. 1976, p. 661-666 Copyright ©D 1976 American Society for Microbiology
Vol. 13, No. 3 Printed in U.SA.
Adherence of Bacteria to Vaginal Epithelial Cells P.-A. MARDH* AND L. WESTROM Institute of Medical Microbiology, University of Lund,* and Department of Obstetrics and Gynecology, University Hospital, S-223 62 Lund, Sweden Received for publication 21 October 1975
Vaginal epithelial cells from healthy women were washed and incubated in tissue culture medium with freshly isolated bacteria of the indigenous vaginal flora and with bacteria of species that have been discussed in conjunction with genital infections. After incubation and washing, the number of bacteria that adhered per cell was determined. The influence on the attachment rate of such factors as variations in the washing procedure, bacterial density, and incubation time was assessed. Lactobacillus acidophilus and other bacterial species that occur in the lower genital tract of healthy women, e.g., some strictly anaerobic species, adhered by significantly lower numbers per cell than Neisseria gonorrhoeae, group B streptococci, and Corynebacterium vaginale. Significantly more freshly isolated gonococci adhered per cell than gonococci that had been passaged on artificial medium. The adherence of gonococci increased with increasing acidity of the test medium.
The ability of bacteria to attach to mucosal epithelial cells seems to have a crucial impact on the establishment of the indigenous bacterial flora. It might also explain the tropism of pathogens and must be a prerequisite for a subsequent bacterial invasion of underlying tissues (cf. reference 11). The adherence of bacteria to exfoliated vaginal cells was tested in an in vitro system. Cells were incubated with bacteria of species belonging to the indigenous flora of the lower genital tract of women and also with bacteria of species that have been discussed in conjunction with genital infections. Under the experimental conditions used, differences in the ability of bacteria of these two groups to adhere to vaginal cells were observed.
Bacteria. The bacteria were isolated from specimens that had been collected from the female genital tract. The following species were studied: Bacteroides fragilis, B. melaninogenicus, group B streptococci, Corynebacterium vaginale (Haemophilus vaginalis), Enterobacter aerogenes, Escherichia coli, Fusobacterium glutinosum, Lactobacillus acidophilus, and Neisseria gonorrhoeae. The bacteria were isolated and subcultured on plates, which consisted of blood agar base no. 2 (Difco) with 4% defibrinated horse blood. Fresh blood agar plates (
Vol. 13, No. 3 Printed in U.SA.
Adherence of Bacteria to Vaginal Epithelial Cells P.-A. MARDH* AND L. WESTROM Institute of Medical Microbiology, University of Lund,* and Department of Obstetrics and Gynecology, University Hospital, S-223 62 Lund, Sweden Received for publication 21 October 1975
Vaginal epithelial cells from healthy women were washed and incubated in tissue culture medium with freshly isolated bacteria of the indigenous vaginal flora and with bacteria of species that have been discussed in conjunction with genital infections. After incubation and washing, the number of bacteria that adhered per cell was determined. The influence on the attachment rate of such factors as variations in the washing procedure, bacterial density, and incubation time was assessed. Lactobacillus acidophilus and other bacterial species that occur in the lower genital tract of healthy women, e.g., some strictly anaerobic species, adhered by significantly lower numbers per cell than Neisseria gonorrhoeae, group B streptococci, and Corynebacterium vaginale. Significantly more freshly isolated gonococci adhered per cell than gonococci that had been passaged on artificial medium. The adherence of gonococci increased with increasing acidity of the test medium.
The ability of bacteria to attach to mucosal epithelial cells seems to have a crucial impact on the establishment of the indigenous bacterial flora. It might also explain the tropism of pathogens and must be a prerequisite for a subsequent bacterial invasion of underlying tissues (cf. reference 11). The adherence of bacteria to exfoliated vaginal cells was tested in an in vitro system. Cells were incubated with bacteria of species belonging to the indigenous flora of the lower genital tract of women and also with bacteria of species that have been discussed in conjunction with genital infections. Under the experimental conditions used, differences in the ability of bacteria of these two groups to adhere to vaginal cells were observed.
Bacteria. The bacteria were isolated from specimens that had been collected from the female genital tract. The following species were studied: Bacteroides fragilis, B. melaninogenicus, group B streptococci, Corynebacterium vaginale (Haemophilus vaginalis), Enterobacter aerogenes, Escherichia coli, Fusobacterium glutinosum, Lactobacillus acidophilus, and Neisseria gonorrhoeae. The bacteria were isolated and subcultured on plates, which consisted of blood agar base no. 2 (Difco) with 4% defibrinated horse blood. Fresh blood agar plates (
