Effects of intrajejunal perfusion and chronic ingestion of Lactobacillus johnsonii strain La1 on serum concentrations and jejunal secretions of immunoglobulins and serum proteins in healthy humans.
OBJECTIVE
Link-Amster reported an increase in serum IgA when healthy subjects ingested a fermented dairy product containing Lactobacillus johnsonii La1. We aimed to assess the effects of La1 on the jejunal secretions and serum concentrations of total and specific immunoglobulins and proteins.


METHODS
Twelve healthy volunteers ingested a fermented milk containing La1 or a control from day 1 till day 28, following a randomised double blind protocol. At days 0 and 28, the jejunum was successively perfused with a control solution and with a La1 suspension. The serum concentrations and jejunal secretions of albumin, orosomucoid, transferrin, alpha 2-macroglobulin, m-IgA, p-IgA, IgG, IgM, secretory component, and specific antibodies against La1 were assessed.


RESULTS
Serum concentrations of IgA slightly increased between d0 and d28 in the group receiving La1 (1.85 +/- 0.64 g/L vs 1.76 +/- 0.76; P = 0.02). The other parameters were not altered.


CONCLUSIONS
This study shows that the immunomodulating effects of La1 ingestion in man are not due to modification of jejunal protein permeability.
Marteau
P
P
INSERM U 290, Hôpital Saint-Lazare, Paris, France.
Vaerman
J P
JP
Dehennin
J P
JP
Bord
S
S
Brassart
D
D
Pochart
P
P
Desjeux
J F
JF
Rambaud
J C
JC
D000907:Antibodies, Bacterial / Q000032:analysis; D001798:Blood Proteins / Q000032:analysis; D004311:Double-Blind Method; D006801:Humans; D007136:Immunoglobulins / Q000032:analysis* / Q000097:blood; D007263:Infusions, Parenteral; D007583:Jejunum / Q000276:immunology / Q000378:metabolism* / Q000502:physiology; D007778:Lactobacillus / Q000276:immunology; D011506:Proteins / Q000032:analysis*; D013997:Time Factors
D000907:Antibodies, Bacterial; D001798:Blood Proteins; D007136:Immunoglobulins; D011506:Proteins