COMPARISON OF IMMUNE-RESPONSES IN PATIENTS INFECTED WITH VIBRIO-CHOLERAE O139 AND O1

Vibrio cholerae O139 has recently emerged as the second etiologic agen t of cholera in Asia, A study was carried out to evaluate the inductio n of specific immune responses to the organism in V. cholerae O139-inf ected patients, The immune responses to V. cholerae O139 Bengal were s tudied in patients by measuring antibody-secreting cells (ASC), as wel l as vibriocidal and antitoxic antibodies in the circulation, These re sponses were compared with those in patients with V. cholerae O1 disea se, Strong immunoglobulin A (IgA) and IgM ASC responses were seen agai nst the homologous lipopolysaccharide or serogroup of V. cholerae. The magnitude and isotype of the responses were similar in O139- and Ol-i nfected patients. Vibriocidal antibody responses were seen against bac teria of the homologous but not heterologous serogroup, and these resp onses reflect the lack of cross-protection between the infections caus ed by the two serogroups, The two groups of patients showed comparable cholera toxin-specific ASC responses, with the Ige isotype dominating over the IgA isotype, as well as comparable antitoxic immune response s in plasma, These results suggest that despite having a polysaccharid e capsule, V. cholerae O139 induces systemic and intestine-derived ASC responses in peripheral blood comparable to those seen in patients wi th V. cholerae O1 disease.