Factor H Binding to PspC of Streptococcus pneumoniae Increases Adherence to Human Cell Lines In Vitro and Enhances Invasion of Mouse Lungs In Vivo

ABSTRACTPneumococcal surface protein C (PspC) binds to both human secretory immunoglobulin A (sIgA) and complement factor H (FH). FH, a regulator of the alternative pathway of complement, can also mediate adherence of different host cells. Since PspC contributes to adherence and invasion of host cells, we hypothesized that the interaction of PspC with FH may also mediate adherence of pneumococci to human cells. In this study, we investigated FH- and sIgA-mediated pneumococcal adherence to human cell lines in vitro. Adherence assays demonstrated that preincubation ofStreptococcus pneumoniaeD39 with FH increased adherence to human umbilical vein endothelial cells (HUVEC) 5-fold and to lung epithelial cells (SK-MES-1) 18-fold, relative to that of D39 without FH on the surface. The presence of sIgA enhanced adherence to SK-MES-1 6-fold and to pharyngeal epithelial cells (Detroit 562) 14-fold. Furthermore, sIgA had an additive effect on adherence to HUVEC; specifically, preincubation of D39 with both FH and sIgA led to a 21-fold increase in adherence. Finally, using a mouse model, we examined the significance of the FH-PspC interaction in pneumococcal nasal colonization and lung invasion. Mice intranasally infected with D39 preincubated with FH had increased bacteremia and lung invasion, but they had similar levels of nasopharyngeal colonization compared to that of mice challenged with D39 without FH.

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New inhibitors of sepiapterin reductase. Lack of an effect of intracellular tetrahydrobiopterin depletion upon in vitro proliferation of two human cell lines.

Journal of Biological Chemistry ◽

10.1016/s0021-9258(18)42807-4 ◽

1992 ◽

Vol 267 (8) ◽

pp. 5599-5607

Author(s):

G.K. Smith ◽

D.S. Duch ◽

M.P. Edelstein ◽

E.C. Bigham

Keyword(s):

Cell Lines ◽

Human Cell ◽

Human Cell Lines ◽

In Vitro Proliferation ◽

Sepiapterin Reductase

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Dicalcin suppresses in vitro trophoblast attachment in human cell lines

Biochemical and Biophysical Research Communications ◽

10.1016/j.bbrc.2021.07.030 ◽

2021 ◽

Vol 570 ◽

pp. 206-213

Author(s):

Ryohei Saito ◽

Hiromasa Satoh ◽

Kayo Aoba ◽

Hajime Hirasawa ◽

Naofumi Miwa

Keyword(s):

Cell Lines ◽

Human Cell ◽

Human Cell Lines

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Antifungal Activity of Flocculosin, a Novel Glycolipid Isolated from Pseudozyma flocculosa

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.49.4.1597-1599.2005 ◽

2005 ◽

Vol 49 (4) ◽

pp. 1597-1599 ◽

Cited By ~ 61

Author(s):

Benjamin Mimee ◽

Caroline Labbé ◽

René Pelletier ◽

Richard R. Bélanger

Keyword(s):

Antifungal Activity ◽

Amphotericin B ◽

Cell Lines ◽

Human Cell ◽

Synergistic Activity ◽

Human Cell Lines ◽

Antifungal Properties ◽

Pseudozyma Flocculosa ◽

In Vitro Antifungal Activity

ABSTRACT Flocculosin, a glycolipid isolated from the yeast-like fungus Pseudozyma flocculosa, was investigated for in vitro antifungal activity. The compound displayed antifungal properties against several pathogenic yeasts. Synergistic activity was observed between flocculosin and amphotericin B, and no significant cytotoxicity was demonstrated when tested against human cell lines.

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Chromosome 7 suppresses indefinite division of nontumorigenic immortalized human fibroblast cell lines KMST-6 and SUSM-1

Molecular and Cellular Biology ◽

10.1128/mcb.13.10.6036-6043.1993 ◽

1993 ◽

Vol 13 (10) ◽

pp. 6036-6043

Author(s):

T Ogata ◽

D Ayusawa ◽

M Namba ◽

E Takahashi ◽

M Oshimura ◽

...

Keyword(s):

Cell Lines ◽

Human Cell ◽

Human Fibroblasts ◽

Fibroblast Cell ◽

Chromosome 7 ◽

In Vitro Mutagenesis ◽

Human Cell Lines ◽

First Case ◽

Normal Human

Using nontumorigenic immortalized human cell lines KMST-6 (KMST) and SUSM-1 (SUSM), we attempted to identify the chromosome that carries a putative senescence-related gene(s). These cell lines are the only ones that have been established independently from normal human diploid fibroblasts following in vitro mutagenesis. We first examined restriction fragment length polymorphisms on each chromosome of these immortalized cell lines and their parental cell lines and found specific chromosomal alterations common to these cell lines (a loss of heterozygosity in KMST and a deletion in SUSM) on the long arm of chromosome 7. In addition to these, we also found that introduction of chromosome 7 into these cell lines by means of microcell fusion resulted in the cessation of cell division, giving rise to cells resembling cells in senescence. Introduction of other chromosomes, such as chromosomes 1 and 11, on which losses of heterozygosity were also detected in one of the cell lines (KMST), to either KMST or SUSM cells or of chromosome 7 to several tumor-derived cell lines had no effect on their division potential. These results strongly suggest that a gene(s) affecting limited-division potential or senescence of normal human fibroblasts is located on chromosome 7, probably at the long arm of the chromosome, representing the first case in which a specific chromosome reverses the immortal phenotype of otherwise normal human cell lines.

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