Donor immunization with Haemophilus influenzae type b (HIB)-conjugate vaccine in allogeneic bone marrow transplantation

Abstract

Bone marrow transplant patients are at increased risk for infections with polysaccharide encapsulated organisms and respond poorly to polysaccharide vaccines. We evaluated the effect of donor immunization with Haemophilus influenzae type b (HIB) polysaccharide-conjugate vaccine on recipient antibody responses following allogeneic bone marrow transplantation. Thirty-two allogeneic transplant patients and their donors were immunized before transplantation with HIB-conjugate, tetanus toxoid and 23-valent pneumococcal vaccines. Following transplantation, patients received HIB-conjugate and tetanus toxoid vaccines at 3, 6, 12, and 24 months and 23-valent pneumococcal vaccine at 12 and 24 months. Thirty-three patients with unimmunized donors were immunized following transplantation in an identical manner. Patients whose donors were immunized had significantly higher total anti-HIB antibody concentrations at 3 months (P = .0001), 6 months (P = .0001), 12 months (P = .0001), and 24 months (P = .002) after transplant compared with patients whose donors were unimmunized. Higher antitetanus toxoid antibody concentrations were also noted in patients with immunized donors, whereas donor immunization with pneumococcal vaccine had no effect on antibody concentrations following transplantation. Donor immunization with HIB-conjugate vaccine resulted in higher antibody concentrations in patients as early as 3 months after allogeneic transplantation and may be an effective strategy to prevent HIB infections.

Use of Licensed Vaccines for Active Immunization of the Immunocompromised Host

“…This supports other studies suggesting that donor immunization primes recipients for early antibody responses to protein-polysaccharide conjugates (285), and may explain why others failed to demonstrate an effect of donor vaccination when recipients were vaccinated 1 year after transplantation (176). It has been suggested that donor immunization with T-independent purified polysaccharide antigens does not prime the recipient to respond to polysaccharide vaccination (176,189).…”

“…The most significant correlate of decreased antibody responses in BMT recipients appears to be T-cell depletion. Neither intravenous immunoglobulin therapy nor graft-versus-host disease has been consistently shown to have an effect on Hib conjugate-induced antibody responses (116,189). Vaccination with a Hib conjugate vaccine has been suggested at 12 and 24 months after either autologous or allogeneic transplantation (8).…”

“…Although their antibody responses were decreased compared to normal subjects, 85% of allogeneic BMT recipients responded to two doses of a PRP-T (HIB-T; Pasteur Merieux) conjugate with antibody levels greater than 1 g/ml (28). Donor and recipient vaccination with Hb-OC before allogeneic BMT followed by recipient vaccination 3, 6, 12, and 24 months after transplantation resulted in higher anti-Hib antibody levels in donor-immunized versus donor-unimmunized recipients (189). This supports other studies suggesting that donor immunization primes recipients for early antibody responses to protein-polysaccharide conjugates (285), and may explain why others failed to demonstrate an effect of donor vaccination when recipients were vaccinated 1 year after transplantation (176).…”

“…In this study, the recipients who received bone marrow from Pneumovax-immunized donors did not have better antibody responses, but the recipients were vaccinated 1 year after donor vaccination. The success of recipient immunization with a Hib conjugate soon after donor vaccination (189) suggests that earlier recipient vaccination might elicit higher antibody levels.…”

Immunization for Bone Marrow Transplant Recipients

“…In a similar study, allogeneic BMT recipients were allocated to one of two groups where the donor was or was not immunized before bone marrow harvest. Patients whose donors were immunized with Hib-conjugate vaccine and TT had higher antibody levels after transplantation and immunization than did patients with unimmunized donors (24). The authors suggested that recipient and/or donor immunization before bone marrow harvest and transplantation may be a strategy to prevent these and other infections in BMT patients (23,24).…”