Key immunity characteristics of diverse stages of brucellosis in rural population from Inner Mongolia, China

Abstract

Background Brucellosis poses a serious threat to human and animal health, particularly in developing countries such as China. The Inner Mongolia Autonomous Region is one of the most severely brucellosis-endemic provinces in China. Currently, the host immune responses functioning to control Brucella infection and development remain poorly understood. The aim of this study is to further clarify the key immunity characteristics of diverse stages of brucellosis in Inner Mongolia. Methods We collected a total of 733 blood samples from acute (n = 137), chronic (n = 316), inapparent (n = 35), recovery (n = 99), and healthy (n = 146) groups from the rural community of Inner Mongolia between 2014 and 2015. The proportions of CD4+, CD8+, Th1, Th2, and Th17 T cells in peripheral blood and the expression of TLR2 and TLR4 in lymphocytes, monocytes and granulocytes were examined using flow cytometry analysis. The differences among the five groups were compared using one-way ANOVA and the Kruskal–Wallis method, respectively. Results Our results revealed that the proportions of CD4+ and CD8+ T cells were significantly different among the acute, chronic, recovery, and healthy control groups (P < 0.05), with lower proportions of CD4+ T cells and a higher proportion of CD8+ T cells in the acute, chronic, and recovery groups. The proportion of Th1 cells in the acute, chronic, and inapparent groups was higher than that in the healthy and recovery groups; however, there was no significant difference between patients and healthy individuals (P > 0.05). The proportion of Th2 lymphocytes was significantly higher in the acute and healthy groups than in the inapparent group (P < 0.05). The proportion of Th17 cells in the acute group was significantly higher than that in the healthy control, chronic, and inapparent groups (P < 0.05). Finally, the highest expression of TLR4 in lymphocytes, monocytes and granulocytes was observed in the recovery group, and this was followed by the acute, chronic, healthy control, and inapparent groups. There was a significant difference between the recovery group and the other groups, except for the acute group (P < 0.05). Moreover, a correlation in TLR4 expression was observed in lymphocytes, monocytes and granulocytes among the five groups (r > 0.5), except for the inapparent group between lymphocytes and granulocytes (r = 0.34). Conclusions Two key factors (CD8+ T cells and TLR4) in human immune profiles may closely correlate with the progression of brucellosis. The detailed function of TLR4 in the context of a greater number of cell types or tissues in human or animal brucellosis and in larger samples should be further explored in the future. Graphical Abstract

The challenge of managing ischemic stroke in brucellosis: a case report

“…Currently, there is a growing interest in studying immune protection mechanisms involving CD4 + and CD8 + T lymphocytes after Brucella infection ( 5 ). Recent studies have found that patients with brucellosis have a reduced proportion of CD4 + T lymphocytes in their peripheral blood but an increased proportion of CD8 + T lymphocytes ( 6 ). Some studies have suggested that Brucella infection disrupts the interaction between B lymphocytes and CD4 + T lymphocytes, thereby increasing the host’s susceptibility to Brucella ( 7 ).…”

Brucella infection and Toll-like receptors

“…The interaction of Brucella with TLR4 on host cells affects the induction of the immune response, and TLR4 plays a role in resistance to Brucella infection ( Campos et al., 2004 ; Dueñas et al., 2004 ; Copin et al., 2007 ; Martirosyan et al., 2012 ; Ma et al., 2015 ; Zhu et al., 2022 ). B. melitensis OMP25 interacted with ferritin heavy polypeptide 1 (FTH1) in human placenta trophoblastic cells (HPT−8) and led to the increase of the levels of TLR4 and inflammatory factors, suggesting that OMP25 serves an important role in intracellular parasitism of Brucella ( Zhang et al., 2022 ).…”

Spatiotemporal distribution and ecological factors of brucellosis among children from 2016 to 2020 in Inner Mongolia, China Short Title： Epidemiological characteristics of brucellosis in children

“…In recent years, the global incidence of brucellosis has risen annually, with 1.6 to 2.1 million new cases of human brucellosis being reported each year [2] . Brucellosis posed a serious threat to human and animal health and was a widespread problem in some developing countries [3] . In 2014, the reported incidence rate of brucellosis was 4.22/100,000 in China, marking the highest rate ever recorded [4] .…”