## 4 Discussion
The observed increase in IL-10 expression following Con A treatment reflects a natural attempt by the immune system to counterbalance inflammation and maintain immune equilibrium. This physiological process highlights IL-10's crucial role in reducing inflammatory damage and maintaining homeostasis during immune responses. In this study, a 150 mg/kg CPA dosage (administered on days 0 and 3) was chosen based on established immunosuppressive models that demonstrate efficacy without excessive toxicity [23; 24]. This two-dose regimen aligns with widely used protocols designed to induce stable immunosuppression while minimizing adverse effects [25; 26; 27]. Furthermore, the post-CPA treatment duration varies across studies, with short-term protocols (\(\leq\)7 days) assessing early-phase immune responses [23; 28], while longer durations (>14 days) focus on extended immunomodulatory effects [29; 30]. Experimental evidence supports the use of 10-14 days of continuous treatment following CPA administration, a strategy that aligns with our study design [14; 31; 32; 33]. To further validate this approach, preliminary experiments were conducted using three different CPA doses (12.5 mg/kg, 70 mg/kg, and 150 mg/kg) (Supplementary Table S1). The results confirmed that administering CPA at 150 mg/kg on days 0 and 3, followed by a 14-day treatment period, provided the most effective and biologically relevant conditions for evaluating immunomodulatory effects. CPA-induced immunosuppression significantly impacts key hematological parameters, including WBC, NEU, LYM, MONO, and EOS, which play essential roles in immune function. WBCs are crucial for immune defense, and their reduction weakens the body'sability to combat infections [34]. NEUs, the primary defense against bacterial infections, are suppressed by CPA, increasing susceptibility to infections [35]. LYMs, including T and B cells, are vital for adaptive immunity, and their decline compromises both humoral and cell-mediated immune responses [36]. MONOs, which differentiate into macrophages and dendritic cells, contribute to pathogen clearance, and their reduction weakens immune surveillance [37]. Lastly, EOS, which are involved in allergic reactions and parasite defense, are also suppressed, potentially disrupting immune homeostasis [38]. Overall, the CPA-induced decline in these parameters indicates significant immunosuppression, underscoring the importance of evaluating the effects of PMT in mitigating these changes. PMT treatment partially restored these parameters, with WBC and EOS levels showing significant recovery in a dose-dependent manner. These findings suggest that PMT can aid in restoring hematological homeostasis, particularly through its effects on WBC and EOS counts, under immunosuppressive conditions. The thymus, a critical immune organ for T cell maturation, was significantly affected by CPA-induced immunosuppression, as evidenced by reduced thymus weight, thymus index, and structural disorganization. PMT treatment (100 and 200 mg/kg) dose-dependently reversed these effects, restoring the thymus weight and thymus index. Histological analysis demonstrated that PMT improved the thymic architecture by reestablishing the boundary between the cortex and the medulla, suggesting a protective effect on the thymus structure. Conversely, the spleen, a key organ responsible for filtering blood and orchestrating immune responses, exhibited reactive hypertrophy in response to systemic stress, inflammation, and cellular damage [39; 40]. CPA-induced cell death and tissue injury result in the release of cellular debris and inflammatory signals, which are processed by the spleen. This leads to the accumulation of immune cells, particularly macrophages and neutrophils, as well as an increase in splenic extramedullary hematopoiesis. These processes contributed to the observed splenic enlargement. Splenic hypertrophy following CPA treatment may also be linked to compensatory immune mechanisms [41; 42].