如今，世界面临着高度传染性疾病的挑战，其中一种初步毒力机制是抑制先天免疫。因此，提升自然免疫力是一种良好的预防策略。我们对几种天然植物提取物 - 辣木、枸杞和旋覆花以及壳聚糖纳米粒子（CS NPs） - 以及与CS NPs结合的提取物对地塞米松免疫抑制（IS）雄性大鼠的免疫学参数进行了调查和比较。植物提取物的总黄酮、酚类和抗氧化活性进行了评估。利用颗粒大小、Zeta电位和傅里叶变换红外光谱分析对CS NPs及其共轭进行了表征。利用能源色散X射线荧光对植物提取物、CS NPs及其共轭的化学分析进行了评估，并在人类肺成纤维细胞（WI-38）和人胚胎肾（HEK-293）细胞系中评估其细胞毒性。对于体内评估，将72只成年雄性大鼠分为9组：对照组、IS组、三种植物提取物组、CS组以及三种植物提取物与CS NPs的共轭组。口服补充剂（日复一日）持续28天。收集肝脏、肾脏和脾脏组织样本进行组织病理学和Ki-67表达分析。结果显示，植物提取物和CS改善了28天时的总白细胞计数、补体3、补体4、干扰素-γ和肿瘤坏死因子水平。然而，植物提取物-CS NPs共轭物在第14天更快并且具有更高的免疫刺激效果。此外，地塞米松引起的脾脏白色髓样萎缩得到缓解，并且所有治疗组中Ki-67的表达升高。总之，Moringa oleifera、Ziziphus spina christi和Saussurea costus提取物与CS NPs的共轭物在低剂量和浓度下表现出更强的和更快的免疫反应，而不会引起肝脏或肾脏损伤。因此，建议在考虑安全性的前提下以较低的剂量和浓度补充这些共轭植物提取物，以提高免疫力。版权所有© 2023 Elsevier B.V.发表。

Nowadays, the world is challenged with highly contagious diseases, one of their preliminary virulence mechanisms is the suppression of innate immunity. Therefore, promoting natural immunity is a good precautionary strategy. we investigated and compared the effects of several natural herbal extracts -Moringa oleifera, Ziziphus spina christi, and Saussurea costus, and chitosan nanoparticles (CS NPs)- as well as conjugated extracts with CS NPs on the immunological parameters of dexamethasone immunosuppressed (IS) male rats. The plant extracts were assessed for total flavonoids, phenolics, and antioxidant activity. The CS NPs and their conjugates were characterized using particles size, zeta potentials, and Fourier-transform infrared spectroscopy analyses. The chemical analysis of the plant extracts, CS NPs, and their conjugates was performed using energy dispersive X-ray fluorescence, and their cytotoxicity was evaluated in human lung fibroblast (WI-38) and human embryonic kidney (HEK-293) cell lines. For in vivo evaluations, 72 adult male rats were divided into 9 groups: control, IS, three plant extracts, CS, and conjugates of the three plant extracts and CS NPs. Oral supplementation (day after day) lasted for 28 days. Liver, kidney, and spleen tissue samples were collected for histopathology and Ki-67 expression analyses. The results revealed that the plant extracts and CS improved the total leukocyte counts, complement 3, complement 4, interferon-gamma, and tumor necrosis factor levels at day 28. However, the plant extract-CS NPs conjugates faster and have higher immunostimulatory effects at day 14. Furthermore, the atrophied white pulp of the spleen induced by dexamethasone was alleviated, and Ki-67 expression was elevated in all the treated groups. Conclusively, the conjugates of Moringa oleifera, Ziziphus spina christi, and Saussurea costus extract with CS NPs demonstrated more potent and rapid immune responses at lower doses and concentrations compared to the plant extracts or CS NPs alone, without causing liver or kidney injuries. Thus, supplementation of these conjugated plant extracts at lower doses and concentrations is recommended to improve immunity while considering safety considerations.Copyright © 2023. Published by Elsevier B.V.