Specific immune response in the respiratory tract after administration of an oral polyvalent bacterial vaccine

Abstract

An oral killed polyvalent bacterial vaccine was assessed in a double-blind trial involving healthy volunteers. Three courses of oral vaccine were given over a 2month period; each course contained 1010 Haemophilus influenzae and 7 x 109 Staphylococcus aureus organisms. Immunity was assessed by monitoring antibody in saliva and serum over a 3-month period. No evidence of a nonspecific effect on immune parameters (immunoglobulin levels and Escherichia coli antibody) was detected in saliva or serum. An increase in H. influenzae antibody in saliva was detected in 55% of subjects receiving the vaccine compared with 6.7% of the placebo group. Antibody was associated with immunoglobulin A (IgA), IgG, and IgM, but the greatest increases over preimmunization levels were detected in the IgA class. No increase in serum antibody levels was detected. Subjects with higher preimmunization levels of salivary antibody to H. influenzae were less likely to respond to the oral bacterial vaccine. No increase in S. aureus antibody was detected in saliva or serum.

Protective effects of orally administered, Klebsiella-containing bacterial lysates in mice

“…The immunogenicity of the Klebsiella, but not the Moraxella component in LW50020, suggests the presence of a Klebsiella-associated immuno-logical adjuvant. According to the current concepts concerning oral immunogenicity [10][11][12]16,17], this adjuvant would target immunodominant antigens of Klebsiella via M cells to the Peyer's patches in the gut, resulting in priming of T cells and the production of Klebsiella-specific IgA in the gut and, eventually, in other mucosal organs. Further study will be directed toward the identification and mode of action (interaction with M cells, priming of T cells, etc.)…”

“…Our interest is in the pathogenesis of opportunistic infections and the possibility to prevent such afflictions by the oral intake of multi-or mono-valent bacterial lysates. The efficacy of such preparations is believed to involve both specific and nonspecific defense mechanisms [16][17][18][19]. In this paper, we concentrate on the protective activity in mice of the Klebsiella-containing, heptavalent lysate LW50020 and of a monovalent Klebsiella lysate, both administered via an intraesophageal catheter.…”

Vaccines for the Future — An Update

“…The oral route potentially has broad applications, as oral immunization may induce immune responses at other mucosal surfaces. Specific local IgA responses in the upper respiratory tract have followed oral immunization with Streptococcus mutans (76), influenza virus (77) and Hemophilus influenzae (78). The concept of a common mucosal immune system involving an intermucosal cell circuit underlies these responses (79) and provides a rationale for utilizing the oral route to protect against mucosal infections at any site.…”

The bacterial lysate Lantigen B reduces the number of acute episodes in patients with recurrent infections of the respiratory tract: The results of a double blind, placebo controlled, multicenter clinical trial

“…Since the first in vivo studies, it was hypothesized that the clinical effects observed were related to the capacity of BL to elicit a specific immune-response against bacterial antigens. Along this line, since the mid 1970s, specific IgA directed against bacterial antigens have been observed in the salivary fluid of treated patients [1][2][3][4] following the oral administration of bacterial lysates. During the 1990s, the description of the toll-like receptor (TLR) family and its functions [5] within the larger context of the pattern recognition receptor (PRR) system explained how the innate immune system was alerted by the presence of different stimuli, mainly represented by bacterial derived structures.…”