Figueroa-Arredondo P, García-Lozano H, Gutiérrez-Cogco L, Valdespino-Gómez J L
Laboratorio de Bacteriología Entérica, Instituto Nacional de Diagnóstico y Referencia Epidemiológicos, México, D.F., Mexico.
Rev Latinoam Microbiol. 1994 Oct-Dec;36(4):277-81.
At the present time there is still in Mexico a diarrhoeal outbreak due to Vibrio cholerae O1. In INDRE we have isolated from the same outbreak last year (jan-apr), 70 strains of Vibrio cholerae Non-O1. These were isolated from patients with a diarrhoeal illness different from cholera. Patients were of different ages and sex, and from various geographic areas. The isolated strains were confirmed by serological agglutination test with polyclonal antisera, and they neither belong to O1 serogroup or O139. We assayed all the 70 strains in Vero cells, searching for cytotoxic effect, probably attributed to cholera toxin, or any other toxin. The strains were screened by PCR for cholera toxin gene detection, and negative results were obtained. We have found only one CT-producer strain, but it was a rough one so, we are not able to affirm that is not a V. cholerae O1 serotype. Vibrio cholerae Non-O1 strains, tested in Vero cells assay, produced cytotoxic effect within 24 h. It was found that 48/70 strains (66.6%), had cytotoxic activity, showing rounding and then lysis of cells. From our results we concluded that this cytotoxic effect, is not cholera toxin related, instead we propose it could be due to an unknown virulence factor, probably a different toxin in mexican Vibrio cholerae Non-O1 strains.
目前，墨西哥仍有由O1群霍乱弧菌引起的腹泻疫情。在国家流行病学、疾病控制和预防研究所（INDRE），我们从去年（1月至4月）的同一疫情中分离出了70株非O1群霍乱弧菌。这些菌株是从患有与霍乱不同的腹泻疾病的患者中分离出来的。患者年龄和性别各异，来自不同地理区域。分离出的菌株通过用多克隆抗血清进行血清学凝集试验进行确认，它们既不属于O1血清群也不属于O139血清群。我们在Vero细胞中对所有70株菌株进行了检测，寻找可能归因于霍乱毒素或任何其他毒素的细胞毒性作用。通过PCR对菌株进行霍乱毒素基因检测筛选，结果均为阴性。我们仅发现一株产霍乱毒素的菌株，但它是粗糙型的，所以我们无法确定它不是O1群霍乱弧菌血清型。在Vero细胞试验中检测的非O1群霍乱弧菌菌株在24小时内产生了细胞毒性作用。发现48/70株（66.6%）具有细胞毒性活性，表现为细胞变圆然后裂解。从我们的结果中我们得出结论，这种细胞毒性作用与霍乱毒素无关，相反，我们认为它可能是由于一种未知的毒力因子，可能是墨西哥非O1群霍乱弧菌菌株中的一种不同毒素。
