Protein Malnutrition Alters Spleen Cell Proliferation and IL-2 and IL-10 Production by Affecting the STAT-1 and STAT-3 Balance

Abstract

Protein malnutrition (PM) is an important public health problem that affects resistance to infection by impairing a number of physiological processes. PM induces structural changes in the lymphoid organs that affect the roles of the immune and inflammatory responses in a crucial way. The activation of different transcription factors, including signal transducer and activator of transcription (STAT) family members, leads to the production of different cytokines, which are mediators essential to mounting adequate immune and inflammatory responses. In this study, malnourished animals presented anemia, leukopenia, and a severe reduction in spleen cellularity, with reduced numbers of most cell populations, as well as increased percentages of CD3(+) and CD4(+) cells. The proliferation rates were reduced, and cells were increasingly observed in the G0/G1 cell cycle phase; further, IL-2 production was reduced, while IL-10 production was increased. In spleen cells from malnourished animals, STAT-3 protein expression was increased, with a concomitant reduction in STAT-1 expression. Knowing that STAT-1 and STAT-3 are key transcription factors in both immunity and inflammatory pathways, these results infer, at least in part, a mechanistic pathway that affects the manner or intensity of the immune response in malnourished individuals, increasing susceptibility to infection.

Nutritional status and immune response in murine experimental Jorge Lobo's disease

“…7,10 An important finding of the present study was the marked reduction in the spontaneous production of IL-2 in inoculated malnourished mice (G1) compared to the other groups, suggesting a deficient Th1 immune response during malnutrition in conjunction with infection. Separate analysis of malnutrition revealed no difference in the spontaneous production of IL-2 between malnourished (G2) and nourished (G4) animals, in agreement with Mello et al [44].…”

“…Separate analysis of malnutrition revealed no difference in the spontaneous production of IL‐2 between malnourished (G2) and nourished (G4) animals, in agreement with Mello et al . .…”

Monoclonal antibody against human Tim‐3 enhances antiviral immune response

“…We also examined the underlying mechanisms by which L3G promotes the expression of pro-inflammatory cytokines. We found that STAT1, which is a transcription factor that regulates the expression of interferons and interleukins, [50][51][52] was involved in the L3Gpromoted cytokine upregulation ( Figure 4). As discussed above, the interaction between Tim-3 and Gal-9 is a negative interaction.…”

A participação da autofagia na regulação da célula-tronco hemopoética em camundongos knockouts para Atg7 e transglutaminase 2

“…Além disso, a desnutrição pode ocasionar alterações psico-motoras, alterações morfológicas e funcionais em diversos órgãos: baço (MELLO et al,2014) pulmões (LIU et al,2014), fígado (GIUSTO et al,2014,alterações no sistema imunológico (MELLO et al,2014) e na matriz extracelular (MEC) (BORELLI et al, 2009). Alterações hematológicas e na MEC pode contribuir para a hipoplasia observada na medula óssea em camundongos desnutridos.…”