- Study of Immune Cells Involved in the Antitumor Effect of Kefir in a Murine Breast Cancer Model
-
Alimohammadi,1,*
- Introduction: Administration of kefir and a kefir cell-free fraction
(KF) to mice injected with breast tumor cells produced,
locally in the mammary gland, different profiles of cells
secreting cytokines. Here, the immune cell populations
in mammary glands affected by the cyclic consumption
of kefir or KF for 2 or 7 d were evaluated using a breast
tumor model. Apoptosis was also assayed as another
mechanism involved in tumor growth delay. The rate
development of tumor cells, IgA(+) cells, and CD4+ and
CD8+ T lymphocytes was monitored in mammary gland
tissues. The number of Bcl-2(+) cells in the mammary
gland was compared with the apoptosis observed in the tumor.
- Methods: Female BALB/c mice from Charles River Laboratories
(Montreal, Quebec, Canada), weighing 19 to 21 g,
were separated into 5 experimental groups: 1) a tumor
control group,istered this dilution showed the best intestinal immune
response without microbial translocation to the visceral
organs (Vinderola et al., 2005). The daily intake of kefir
was 3.1 ± 0.3 mL/mouse.
- Results: Different cytokine profiles were reported for mice injected
with the breast tumor cells that received 2 or 7
d of cyclical administration of kefir or KF. This result
suggests that oral administration of this fermented
product or its cell-free fraction induced the activation
of different cells in mammary glands compared with
those activated only for tumor injection
- Conclusion: The present study allows a better understanding of
the mechanisms involved in the antitumor effect observed
in mice administered kefir or KF. The importance
of an adequately balanced local immune response
in the mammary glands to avoid tumor growth was
shown. The importance of nonmicrobial components released
during milk fermentation and the period of administration
needed to obtain beneficial antitumor effects
was also reported. Other mechanisms related to
estrogen synthesis in the mammary gland could also
be involved in the effect observed with kefir administration.
- Keywords: kefir