Immune and Iron Metabolism Responses During the Acute Phase of Experimental Hookworm Infection in the Ancylostoma ceylanicum-Hamster Model

Acta Parasitologica (2026) 71:103 https://doi.org/10.1007/s11686-026-01267-4 RESEARCH Immune and Iron Metabolism Responses During the Acute Phase of Experimental Hookworm Infection in the Ancylostoma ceylanicumHamster Model William Pereira Alves1 · Vivian Jordania da Silva2 · Élida Mara Leite Rabelo3 · Luis Fernando Viana Furtado4 Received: 20 January 2026 / Accepted: 11 March 2026 © The Author(s) 2026 Abstract Hookworm infections continue to impose a substantial burden on human and animal health, but the early host responses that influence parasite establishment are not fully characterized. Experimental models that reproduce key features of hookworm biology and host-parasite interactions remain essential for advancing translational research. In this study, we examined hematological, biochemical, immunological, and parasitological parameters during the acute phase of experimental hookworm infection using the Ancylostoma ceylanicum-Mesocricetus auratus model, a small-animal system widely employed for mechanistic studies of hookworm infection. Animals were evaluated at 7 and 20 days post-infection. Hematological indices and serum iron concentrations did not differ between infected and control groups during the acute phase. In contrast, infected animals showed increased splenic mass at 20 days post-infection, indicating immunological activation. Hepatic hepcidin expression was markedly reduced, suggesting an early alteration in systemic iron regulation. Analysis of inflammatory mediators revealed selective modulation of cytokine expression, with reduced interleukin-6 transcript levels at 20 days post-infection, whereas tumor necrosis factor alpha expression remained unchanged. Parasitological analyses demonstrated progressive parasite establishment, with fecal egg output detected from 14 days post-infection and reaching approximately 300 eggs per gram by day 18, consistent with the onset of patency. Taken together, these data indicate that acute hookworm infection induces coordinated changes in immune responses and iron metabolism before the development of overt hematological alterations. Keywords Ancylostoma ceylanicum · Hookworm infection · Iron metabolism · Hepcidin · Immune response · Experimental model Introduction Luis Fernando Viana Furtado 1 Universidade Federal de Minas Gerais, Hospital das Clínicas, Avenida Professor Alfredo Balena, 110, Santa Efigênia, Belo Horizonte, Minas Gerais CEP 30130-100, Brazil 2 Prefeitura Municipal de Sabará, Centro de Controle de Zoonoses, Avenida Charles Gonort, Rosario I, Sabará, Minas Gerais CEP 34505620, Brazil 3 Departamento de Parasitologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Avenida Presidente Antônio Carlos, 6627, Pampulha, Belo Horizonte, Minas Gerais CEP 31270-901, Brazil 4 Departamento de Análises Clínicas e Toxicológicas, Faculdade de Farmácia, Universidade Federal de Minas Gerais, Avenida Presidente Antônio Carlos, 6627, Pampulha, Belo Horizonte, Minas Gerais CEP 31270-901, Brazil Hookworm infection remains a major public health concern, particularly in low- and middle-income countries, where it is among the most prevalent neglected tropical diseases [5]. In humans, infection is mainly caused by three species, listed here according to their global prevalence: Necator americanus, Ancylostoma duodenale, and Ancylostoma ceylanicum [19, 30]. Several animal species also act as natural hosts for hookworms, especially dogs and cats, which are commonly infected by A. caninum, A. braziliense, and A. tubaeforme [21]. These hematophagous nematodes attach to the intestinal mucosa and feed on host blood, resulting in chronic intestinal blood loss [17]. As a consequence, hookworm disease remains one of the leading causes of iron-deficiency anemia worldwide [4, 27]. 13 103 Page 2 of 7 The development of hookworm-associated anemia reflects the interaction between iron metabolism, erythropoiesis, and host immune responses [3, 10]. Blood loss induces compensatory mechanisms aimed at maintaining iron availability and red blood cell production, including the regulation of hepcidin (HAMP), erythroferrone (ERFE), and erythropoietin (EPO) [18, 22]. In parallel, inflammatory cytokines may affect both erythropoiesis and iron distribution, contributing to anemia of inflammation [34]. How these pathways are coordinated during hookworm infection, particularly at early stages, remains incompletely understood. Previous studies have largely focused on the chronic phase of A. ceylanicum infection and have demonstrated sustained alterations in iron homeostasis and immune regulation [12]. In contrast, the early events that precede these long-term changes are less well characterized. The acute phase represents a critical window during which the host initially responds to infection, activating immune and metabolic pathways that may influence the subsequent development of anemia. In the present study, we investigated the regulation of iron metabolism and inflammatory mediators during the acute phase of experimental hookworm infection. These findings complement previous observations from the chronic phase and provide a more integrated view of the mechanisms linking parasite-induced blood loss to anemia. To address this question, we used the A. ceylanicum-Mesocricetus auratus experimental model, which supports intestinal establishment and patent infection and has been widely applied in mechanistic studies of hookworm disease [12, 29]. Although parasite establishment in hamsters is influenced by host age, this system remains suitable for controlled investigation of early host immunometabolic responses. Material and Methods Ethics Statement and Experimental Design All experimental procedures were conducted in accordance with the ethical principles established by the Brazilian National Council for the Control of Animal Experimentation (CONCEA) and national legislation governing the scientific use of animals (Law No. 11.794/2008). The study protocol was approved by the local Institutional Animal Care and Use Committee (Protocol No. 13/2017). Female golden hamsters (M. auratus), four to six weeks of age, were individually identified and randomly allocated to experimental groups according to infection status and sampling time. Animals were orally inoculated by gavage with 100 third-stage larvae (L3) of A. ceylanicum. 13 Acta Parasitologica (2026) 71:103 Two experimental time points were selected to evaluate the acute phase of infection: 7 days post-infection (dpi), corresponding to early parasite establishment, and 20 dpi, representing the transition to egg production. At each time point, infected and non-infected groups were analyzed as follows: NI7 (non-infected, 7 dpi; n = 7), AI7 (infected, 7 dpi; n = 7), NI20 (non-infected, 20 dpi; n = 7), and AI20 (infected, 20 dpi; n = 7). Fecal samples were collected starting at 10 dpi and subsequently every two days to monitor parasite establishment and egg shedd (...truncated)