[Therapeutic mechanisms of interferon-beta and intravenous immunoglobulin for experimental peripheral neuropathy]

To explore the therapeutic mechanisms of interferon-beta (IFN-beta) and intravenous immunoglobulin (IVIG) for experimental peripheral neuropathy induced by Campilobacter jejuni (Cj) lipopolysaccharide (LPS).

Forty healthy Wistar rats weighing 205 - 230 g were divided into IFN-beta, IVIG, IFN-beta plus IVIG and control groups. After the immune neuropathy was induced in the rats by Cj LPS, IFN-beta (1.3 microg/kg) was given by subcutaneous injection to the rats every other day for 6 weeks; IVIG [400 mg/(kg x d)] was given to the rats for five days, every other week for two times and IFN-beta [1.3 microg/(kg x d)] and IVIG [400 mg/(kg x d)] were given to the rats on the same days. Meanwhile, the control group was given PBS. The sera were collected in the 2nd, 4th and 6th week after therapy, the titers of anti-GM(1) IgG, MMP-9 and TNF-alpha in sera of immunized rats were measured by ELISA; histological study of sciatic nerve was performed and IgG on sciatic nerve was detected by immunohistochemistry in the 6th week.

(1) There were no significant differences in titers of anti-GM(1) IgG, MMP-9 and TNF-alpha among the 3 therapeutic groups and control group after therapy for 2 weeks (P > 0.05). (2) The titers of anti- GM(1) IgG, MMP-9 or TNF-alpha in the control group were much higher than those of the IFN-beta group, the IVIG group or the IFN-beta and IVIG group after therapy for 4 weeks (P > 0.01) and there were no significant differences in titers of antibody among the 3 therapeutic groups (P > 0.05); the titers of MMP-9 or TNF-alpha in the IFN-beta and IVIG group were lower than those of the IFN-beta group or the IVIG group (P < 0.05). (3) The titers of anti-GM(1) IgG, MMP-9 or TNF-alpha in the control group were much higher than those of the IFN-beta group, the IVIG group or the IFN-beta with IVIG group after therapy for 6 weeks (P > 0.01); the IFN-beta with IVIG group had much lower levels of all indexes than the IFN-beta group or the IVIG group (P < 0.01).

IFN-beta and IVIG showed therapeutic effects on immune peripheral neuropathy through inhibiting the humoral and cellular immunity simultaneously in the peripheral neuropathy induced by CJ LPS, treatment with combined IFN-beta and IVIG was more effective.