Asymptomatic Borrelia-seropositive individuals display the same incidence of Borrelia-specific interferon-gamma (IFN-gamma)-secreting cells in blood as patients with clinical Borrelia infection.
Borrelia Lyme disease is a complex disorder that sometimes becomes chronic. There are contradictory reports of experimental Borrelia infections regarding which type of T cell cytokine responses, i.e. Th1 or Th2, are needed to eradicate the Borrelia spirochaetes. In human borreliosis a predominance of Borrelia-specific Th1-like responses has been shown. In this study, spontaneous, as well as Borrelia-specific, secretion of IFN-gamma (Th1) and IL-4 (Th2) in Borrelia-seropositive healthy asymptomatic individuals (n = 17) was investigated in peripheral blood by a sensitive ELISPOT assay, and compared with previously reported responses in patients with clinical Borrelia infection (n = 25). The seropositive asymptomatic individuals displayed the same predominance of Borrelia-specific IFN-gamma-secreting cells as the patients with clinical Borrelia infection. Interestingly, the proportion of spontaneously IL-4-secreting cells, reflecting the unstimulated in vivo secretion, was lower in the seropositive asymptomatic individuals compared with patients with chronic Borrelia infections (n = 13, P = 0.02), whereas no such difference was found compared with subacute Borrelia infections (n = 12). These findings indicate that IFN-gamma secretion alone is not sufficient to eliminate Borrelia spirochaetes in humans, although IFN-gamma may still have a beneficial role in borreliosis acting in concert with other mechanisms.
Ekerfelt
C
C
Department of Neuroscience and Locomotion, Faculty of Health Sciences, University Hospital, Linköping, Sweden.
Forsberg
P
P
Svenvik
M
M
Roberg
M
M
Bergström
S
S
Ernerudh
J
J
D000328:Adult; D000368:Aged; D000907:Antibodies, Bacterial / Q000097:blood; D000942:Antigens, Bacterial; D015748:Borrelia burgdorferi Group / Q000276:immunology*; D005260:Female; D006801:Humans; D007371:Interferon-gamma / Q000097:blood / Q000378:metabolism*; D015847:Interleukin-4 / Q000097:blood / Q000378:metabolism; D008193:Lyme Disease / Q000097:blood / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D018417:Th1 Cells / Q000276:immunology; D018418:Th2 Cells / Q000276:immunology
D000907:Antibodies, Bacterial; D000942:Antigens, Bacterial; D015847:Interleukin-4; D007371:Interferon-gamma