Study of the Effect of Tumor Necrosis Factor Alpha (TNF-α) Antagonist (Adalimumab) on Giardiasis in Mice

• Published in: QJM : An International Journal of Medicine 2024-07, Vol.117 (Supplement_1)
• Main Authors: Habib, Faiza S M, Badawy, Abeer F, Abd Elhafiz, Hala E, Thabet, Engy E
• Format: Article
• Language: English
• ISSN: 1460-2725; 1460-2393
• DOI: 10.1093/qjmed/hcae070.435

Giardia lamblia (G. lamblia) is the most common worldwide intestinal protozoal. Serum TNF-α contributes to the recovery from Giardia lamblia infection especially in the first and second week of infection. TNF-α antagonists are biologics used to treat many inflammatory diseases as rheumatoid arthritis. The present study aimed to study the effect of TNF-α antagonist (Adalimumab) on experimental giardiasis in mice by parasitological and histopathological examination. A total of 45 parasite-free laboratory-bred Swiss albino mice included into 2 main groups: test group and control group were used. Test group included mice infected with G. lamblia and receiving three intraperitoneal Adalimumab injections from days 9 till 15 post infection (pi). This group was further subdivided into 3 subgroups (Ia, Ib, Ic) according to Adalimumab doses which were 1.5, 3 and 6 mg/kg BW, received, respectively. Control group (non-Adalimumab-treated group) included a non-infected healthy group and Giardia -infected group. Monitoring the serum TNF-α level in all mice was done on two occasions (day 16 and 28 pi) by ELISA to follow variation in its level with and without administration of the drug. Infection outcome was assessed by following cyst shedding in stools of infected mice on intermittent days, counting trophozoites in intestinal wash, registering weight of animals, and recording pathological changes occurring in histopathological sections from small intestine. Highly significant increase in serum TNF-α was recorded in infected control mice on day 16 post-infection than in normal control group. Similarly, a significant increase in TNF-α level in the 3 test subgroups but attaining significant lower levels. On day 28 post infection, serum TNF- α level decreased in all infected mice with no significant differences being higher in infected control group than in non-infected control group. On assessing the effect of decreased serum TNF-α by the drug on infection outcome, highly significant increases in cyst shedding were recorded in the test group specifically group receiving 3 mg/kg BW than in control infected group on day 16 pi, and in trophozoite counts on day 28 pi. Mice weight gain was highly significant being more in control non-infected group than in control infected group. It was significantly lower in test group than normal infection control. The intestinal sections of test subgroups showed moderate to severe inflammatory reaction with more inflammatory cellular infiltra