Background: Currently, colorectal cancer (CRC) ranks as the third most common cancer and the second leading cause of cancer-related mortality worldwide. CRC frequently metastasizes to the liver (50%), lungs (10–15%), peritoneum (4%), bones (10.7%–23.7%), brain (0.3%–6%), and spinal cord. Approximately 35% of CRC cases are diagnosed before distant metastasis, 36% upon lymph node involvement, and 23% after distant organ metastasis. Although several studies have established primary tumor models in mice in our country, there are limited studies on experimental lung metastasis models, prompting the need for this research. Aim: To establish and evaluate a lung metastasis model of colorectal cancer in C57BL/6J mice using the MC38 cell line. Materials and Methods: This study was conducted at the Institute of Biomedical Sciences, Mongolian National University of Medical Sciences. Approval was obtained from the Ethics Review Board of the Mongolian National University of Medical Sciences (2023/3-09) and all laboratory safety regulations and protocols were strictly followed. Male C57BL/6J mice bred at the Experimental Animal Center of Mongolian National University of Medical Sciences were used. MC38 murine colorectal carcinoma cells were cultured and injected intravenously (via the tail vein) at a concentration of 0.25×10⁶ cells per mouse (n=12) to induce lung metastasis. Histological analysis was subsequently performed. Results: Histological examination revealed significant alterations in lung tissue architecture, characterized by areas of dense infiltration by pleomorphic, hyperchromatic cells, disrupting the normal alveolar structure. No histological abnormalities were observed in other organs. Conclusion Intravenous injection of MC38 colorectal adenocarcinoma cells into the tail vein of C57BL/6J mice successfully induced lung metastases, characterized by hyperchromatic, pleomorphic cell infiltrates forming glandular structures within the lung parenchyma.

Background: Organ transplantation has been rapidly advancing in Mongolia in recent years. The number of successful kidney, liver, and bone marrow transplants performed in national central hospitals has been increasing annually. While the number of successful kidney transplants is increasing, post-transplant immune monitoring remains insufficiently studied. Aim: To assess post-transplant immune status by analyzing inflammatory cytokine levels in kidney transplant recipients Materials and Methods: A prospective cohort study was conducted at the First Central Hospital of Mongolia. Serum samples from kidney transplant recipients were analyzed using flow cytometry to measure the levels of 13 inflammatory cytokines, including TGF-β1, PAI-1, sTREM-1, PTX3, sCD40L, sCD25 (IL-2Ra), CXCL12 (SDF-1), sST2, sTNF-RI, sTNF-RII, sRAGE, CX3CL1 (Fractalkine), and sCD130 (gp130). Statistical analysis was performed to assess the results. Results: The mean creatinine level significantly decreased on post-transplant days 7 and 30 compared to pre-transplant levels (p<0.001, ANOVA). No statistically significant difference was found in the 13 cytokine levels between the high risk and low-risk groups based on creatinine levels on post-transplant day 30 (p>0.05). However, the levels of TGF-β1, CX3CL1, sTREM-1, and sTNF-RI showed statistically significant differences between post-transplant days 7 and 30 (p<0.05). No significant correlation was found between the measured cytokine levels and CRP (p > 0.05). On post-transplant day 7, sTREM-1 had a weak correlation with TGF-β1 (r=0.40, p=0.02) and sTNF-RI (r=0.36, p=0.05) but showed a strong correlation with CX3CL1 (r=0.65, p=0.0001). On post-transplant day 30, sTREM-1 remained strongly correlated with CX3CL1 (r=0.73, p=0.0001) and moderately correlated with sTNF-RI and TGF-β1 (r=0.45, p=0.01). Conclusions 1. The levels of TGF-β1, CX3CL1, sTREM-1, and sTNF-RI significantly varied between post-transplant days 7 and 30 (p< 0.05, T-test). 2. On post-transplant day 30, these cytokines were not correlated with CRP but were interrelated among themselves.

Background: Establishment of quantitative reference intervals of white blood cells and its subpopulations using a high accuracy analytic system is essential for clinical medicine, public health, and anthropology. We are unable to identify peer-reviewed literature sources describing white blood cell counts and their subpopulations using monoclonal antibodies to specific surface antigens in healthy Mongolians. This study aimed to measure the counts of white blood cells and their subpopulations in healthy Mongolians using flowcytometry. Materials and Methods: The absolute number (cell/L) of leukocytes (CD45+), granulocytes, monocytes and lymphocytes were measured by Magnetic Activated Cell Sorting Assay (MACSQuant Analyzer 10) in 287 blood donors (158 males and 129 females) 17-64 years of age (mean age 33.1±12.4). Peripheral blood samples were collected at the time of blood donation at the National Center for Transfusion Medicine. Results The mean values of leukocytes and granulocytes were lower in donors over 30 years of age (ANOVA: F=4.408, p=0.002 and F=5.685, p=0.001) and regression analysis demonstrated indirect correlation between counts of these cells and age of donors (r= - 0.198, p=0.001 and r=-0.221, p=0.001, respectively). Gender-related differences in white blood cell counts were not found.
Mean value of lymphocyte count in donors investigated in spring (May and March, n = 87; 2224.6±775.3) was significantly higher than those in winter (December – February, n=180; 1613.2±454.3, p=0.001) and autumn (October, n=20; 1576.1±438.6, p= 0.001).
Comparing of our findings with the data from available literature shown that healthy Mongolians have lower leukocyte count compared with Koreans, Chinese Han population and lower mean value of lymphocyte count comparing with Korean, Chinese Han population, and Arabian (Saudi Arabia) populations.

Background: The first confirmed case of COVID-19 in Mongolia was reported on November 11, 2020. In response, the government imposed a nationwide lockdown, which significantly impacted the population’s mental health. Heightened levels of stress, anxiety, loneliness, and depression during the pandemic altered individuals’ psychological stability and behavior. Personality traits—defined as relatively stable patterns of emotion, cognition, and behavior—play a key role in stress responses and emotional regulation under pressure. Emerging evidence suggests that these psychological factors may influence the immune system’s responsiveness, including vaccine-induced antibody production. Aim: To evaluate the association between post-vaccination antibody responses and personality types following two doses of COVID-19 vaccines. Materials and Methods: A total of 738 participants who received two doses of COVID-19 vaccines (AstraZeneca ChAdOx1, n=29; Pfizer-BioNTech, n=119; Sinopharm BBIBP, n=590) and had no prior SARS-CoV-2 infection were enrolled. Serum samples were collected 21–28 days after the second dose, and SARS-CoV-2 RBD (S) IgG antibodies were measured using ELISA (Proteintech Inc., USA). Personality types were assessed using a 56-item temperament questionnaire developed by A. Belov, categorizing individuals into classical temperament types (choleric, phlegmatic, sanguine, melancholic). Logistic regression and ROC analysis were used to examine associations between personality types and antibody response. Results: The presence of an antibody response was significantly higher among individuals with a melancholic temperament, and significantly lower among those with a phlegmatic temperament. Furthermore, antibody titers were higher in participants with melancholic and sanguine temperaments and lower in those with a phlegmatic type. Conclusions 1. During the early period following the second dose of COVID-19 vaccination, the antibody response was higher in individuals with a pure melancholic temperament, while it was lower in those with a phlegmatic temperament. 2. After the second dose of the Sinopharm BBIBP COVID-19 vaccine, antibody titers were higher in individuals with pure melancholic and sanguine temperaments, and lower in those with a phlegmatic temperament.

Background: Cancer incidence and mortality are steadily increasing both globally and in Mongolia. As these rates rise, traditional Mongolian medicine has long utilized herbal formulas for the treatment of gastric and esophageal cancers and precancerous conditions. One such formulation—Hot Natured 3 Herbs (HN3H)—comprises three species from the Ranunculaceae family: Atragene sibirica L., Ranunculus repens L., and Pulsatilla bungeana L.. However, scientific validation of its anti-tumor effects is essential. This study aimed to investigate the effect of HN3H in a tumor-induced animal model. Aim: To identify the biologically active compounds of HN3H and evaluate their effect in an experimentally induced tumor model in animals. Materials and Methods: The three herbs comprising HN3H—Atragene sibirica L., Ranunculus repens L., and Pulsatilla bungeana L.—were collected during their flowering stage (May–June) in Khishig-Undur, Bulgan province, and dried according to official procedures. Extraction was carried out by maceration in 96% ethanol at a 1:10 ratio. The concentrated extract was suspended in water (1:1) and successively fractionated with dichloromethane, ethyl acetate, butanol, chloroform, and n-hexane. The study was approved by the Research Ethics Committee of the Mongolian National University of Medical Sciences (Protocol №2020/03-04). A colorectal cancer model was established by subcutaneous injection of MC-38 cells (Kerafast, USA) into C57BL/6 mice. Immunohistochemistry was performed using CK20, CDX2, Ki67, and p53 antibodies at 1:100 and 1:200 dilutions. Results: The ethanol extract of HN3H contained 2.98±0.04% total phenolics and 2.16±0.05% total flavonoids. Body weight and tumor volume were measured daily with three repetitions. All groups showed a time-dependent increase in body weight. Mice in groups 1A and 1B received ethanol extract at 50 and 100 mg/kg doses; groups 2A and 2B received dichloromethane extract at the same doses. The negative control group was administered 0.5 mg/kg PBS orally, while the positive control group received intraperitoneal injections of 5-fluorouracil (5FU) at 10 mg/kg twice a week. Tumor growth increased in a time-dependent manner across groups. Compared to the negative control, tumor volumes in four treatment groups showed statistically significant reduction (p˂0.05), while no significant difference was observed when compared to the positive control (p=0.08). Histological analysis revealed necrosis in all groups, with variation in extent. Conclusion The ethanol extract of HN3H exhibited moderate levels of phenolic compounds and a high concentration of flavonoids. HN3H extract inhibited tumor progression and activated lymphocyte-predominant inflammation in tumor tissues, indicating potential anti-tumor activity (p˂0.05).