Host Modification of the Adherence Properties of Chlamydia trachomatis

Abstract

The adherence of Chlamydia trachomatis LGV440(Ll) to human HeLa 229 and mouse McCoy cells was stimulated by the lectin wheat germ agglutinin (WGA) and inhibited by the sugars Nacetyl-D-glucosamine, N-acetyl-D-galactosamine and chitobiose, but only when the chlamydiae had been passaged several times in HeLa cells. After passage in McCoy cells, the lectin and the sugars elicited little response. The non-LGV serovar UW-3 1 (K), however, differed from LGV440(L1) in that, regardless of passage, the lectin and sugar effects were observed only in HeLa cells. Affinity chromatography on W GA-agarose confirmed that HeLa-grown LGV-44O(L1) bound to a significantly greater extent relative to McCoy-grown chlamydiae. In addition, participation of heterogeneous chlamydia1 ligands was suggested by the observation that the adherence of heated (60 "C, 5 min) UW-3l(K) to HeLa cells at 37 "C was not inhibited at all, but at 5 "C, the adherence rate was greatly reduced, indicating the participation of heatstable as well as heat-labile ligands. These data are interpreted to indicate that the passage history of C. trachomatis results in the acquisition of altered surface components that participate in the initial interaction of the bacterium with the host.

Extensive heterogeneity of the protein composition of Chlamydia trachomatis following serial passage in two different cell lines

“…We had speculated that this intracellular pathogen might acquire surface antigens that enable it to escape the host's immune surveillance system (Bose & Goswami, 1986). The surface protein labelling and the immunoblotting data presented here reinforce this hypothesis, implying that host-specific proteins may be involved in the immune response mechanism.…”

“…another genital serovar, U W 3 l ( K ) , in the alternative host cell McCoy, a mouse fibroblastic cell line, the chlamydiae neither bound to the lectin columns nor showed the lectin-induced enhancement of adherence to the host cells (Bose & Goswami, 1986). Infectivity assays confirmed the affinity chromatography and the adherence data.…”

“…This study was initiated to determine if the host-passagedependent altered adherence of C. trachomatis to mammalian cells (Bose & Goswami, 1986) resulted from the acquisition of host-specified proteins that mediated this step, Data presented here indicate that numerous protein differences develop between the same serovar of chlamydiae after growth in different hosts. These unique host-specified chlamydial proteins include several that are surface-exposed (Figs 1 and 2, Table 1).…”

“…C . trachomatis serovars LGV440 (Ll) and E were grown in monolayer cultures of mycoplasma-free HeLa 229 and McCoy cells (Bose & Goswami, 1986). Infected cells were detached with sterile glass beads, disrupted by sonication, and the EB purified free of contaminating host material and chlamydial reticulate bodies (Vretou et al, 19896).…”

“…Using several lectins as probes to identify the chlamydial ligands responsible for the initial adherence of the elementary bodies (EB) to host cell membrane, we reported that treatment of the host cells with wheat germ agglutinin resulted in a lectin-dose-dependent enhancement of adherence (Bose et al, 1983). In a recent study we noted that the adherence of HeLa-but not McCoy-grown C. trachomatis was specifically stimulated when the host cells had been pretreated with the lectin (Bose & Goswami, 1986). In addition, affinity chromatography of 2P-labelled, highly purified EB on agarose-bound WGA showed that the purified EB of HeLa-grown C. trachomatis serovar LGV440 (Ll) bound to the lectin gel and could be eluted with buffer containing N-acetylglucosamine.…”