Background/Objectives: The pandemic caused by SARS-CoV-2 boosted the development of different vaccine models. In parallel, yeasts stand out as a vaccine platform in healthcare biotechnology. Species such as Saccharomyces cerevisiae and Pichia pastoris can express heterologous proteins, which are capable of inducing specific antibodies and can perform as an attractive vaccine vehicle with immunomodulating properties due to their cell wall composition. Furthermore, the yeast surface display system facilitates antigen presentation to immune cells. We developed an oral vaccine based on P. pastoris displaying a synthetic antigen composed of Spike and Nucleocapsid epitopes. Methods: The vaccine was administered to BALB/c mice. Systemic immune response was measured through antibody detection in blood samples, and mucosal immunity was assessed via IgA levels in feces. Histopathological analysis of intestinal and gastric tissues was also conducted. Results: The yeast-based vaccine elicited a humoral immune response, reflected in the production of neutralizing antibodies and elevated levels of IgG2a and IgG2. No structural alterations or pathological changes were observed in gastrointestinal tissues. Conclusions: This study demonstrates the feasibility of using P. pastoris as an oral vaccine delivery system, supporting previous findings with other yeast species such as Saccharomyces cerevisiae, and highlighting its potential in developing effective mucosal vaccines.

Bronchoalveolar lavage (BAL) is a non-invasive bronchoscopic technique used to aspirate cells from the pulmonary interstitium, initially applied to detect neoplastic cells but later expanded for microbiological studies, leukocyte counts, molecular analyses, and immunophenotyping. This broader approach has linked BAL to the study of interstitial lung diseases (ILD). Despite its use since the 1970s, standardization of BAL cytopathological analysis is lacking, hindering its routine clinical application. The limited number of studies, particularly in Southern Hemisphere countries, reflects challenges in refining laboratory procedures and cytological findings. This article discusses the diagnostic potential of BAL when combined with clinical and radiological data. Integrating cytomorphologic findings with molecular techniques enhances its accuracy, particularly for cases with undefined etiopathogenesis, offering improved diagnostic and follow-up capabilities. The results make it clear that BALF cytology helps tell the difference between different types of ILDs. They also show that it is a useful tool for monitoring and diagnosing lung diseases.

The presence of thyroid nodules is a frequent finding in the adult population, most of which are benign lesions, while malignant tumors generally have a good prognosis. However, undetermined lesions generally lead to possibly unnecessary surgical procedures, reinforcing the need for complementary diagnostic methods capable of ensuring more assertive clinical approaches. Matrix metalloproteinases (MMPs) are endopeptidases associated with the remodeling of the tissue matrix, and are regulated by tissue inhibitors of metalloproteinases (TIMPs), both of which are involved in tumorigenic processes and neoplastic progression. This study analyzed cytological samples from 90 patients treated at the Hospital das Clínicas of the Federal University of Pernambuco (HC/UFPE) between 2015 and 2017. Clinical-pathological and immunocytochemical (ICQ) evaluations for MMP-9 and TIMP-2 were carried out, with statistical analysis including Spearman's correlation and logistic regression. Statistically significant differences in MMP-9 and TIMP-2 immunoreactivity between benign, atypical and malignant lesions were observed, with MMP-9 and TIMP-2 assisting in the probable exclusion or confirmation of papillary thyroid carcinoma (PTC), respectively. It was therefore concluded that MMP-9 and TIMP-2 are promising diagnostic biomarkers, able to complement pre-surgical cytological analysis of nodular thyroid lesions.

The healing of infected diabetic wounds with methicillin-resistant Staphylococcus aureus (MRSA) is one of the greatest challenges in medicine, mainly due to resistance to traditional antibiotics, requiring alternative strategies. This study aimed to evaluate the use of Cassia grandis galactomannan gel, with or without Cratylia mollis lectin (Cramoll), in skin wounds (Ø = 0.8 cm) on the backs of diabetic mice infected or not with MRSA. After confirmation of diabetes induced by a single dose of alloxan monohydrate (200 mg/kg), the animals were divided into 4 groups (n = 15) and treated as follows: saline solution, negative control (GDNC); galactomannan gel (GDG); Cramoll solution (100 µg/mL) (GDC); and galactomannan gel containing Cramoll (GDGC), in daily doses of 100 μL of each substance for 12 days. After macroscopic and microscopic evaluation of the wounds, GDGC demonstrated greater healing efficiency and was selected for the treatment of infected skin wounds with 50 μL of the 1x108 CFU/mL MRSA suspension. Infected diabetic animals (DI) were divided into 4 groups (n=15) and treated as follows: galactomannan gel containing Cramoll (GDIGC); galactomannan gel containing Cramoll+mupirocin (GDIGCM); saline, negative control (GDICN); mupirocin, positive control (GDIMPC). The results revealed that GDIGC presented greater wound contraction (p<0.05) compared to GDIMPC; however, histopathological analyses confirmed that the galactomannan gel containing Cramoll+mupirocin (GDIGCM) significantly accelerated the healing process due to the synergistic effect between gel, Cramoll, and the antibiotic, standing out as a promising alternative for the healing of infected wounds.

Thyroid cancer (TC) is the seventh most common cancer and the twenty-fourth most deadly, according to GLOBOCAN estimates for 2022. The diagnosis of TC is confirmed by histopathological analysis after surgical biopsy, in addition to previous ultrasound and cytopathological evaluations. Despite this, TC still lacks a definitive molecular classification, capable of not only identifying tumors in terms of their cellular origin, but also distinguishing them in terms of aggressiveness, benign or malignant nature and prognosis. This study investigated the potential of matrix metalloproteinase 26 (MMP-26) as a complementary biomarker for the diagnosis of nodular thyroid lesions. Fifty histological blocks, including healthy thyroid tissue, nodular goiter and papillary thyroid carcinoma (PTC), were analyzed using immunohistochemistry. The results showed significant differences in MMP-26 immunoreactivity between healthy thyroid tissue, nodular goiter and PTC, as shown by Spearman's analysis (p<0,001), Chi-square (p<0,001) and logistic regression (p<0,001). However, there were no significant differences between MMP-26 immunoreactivity and clinical-pathological data. MMP-26 showed good sensitivity (93,3% and 100%) and negative predictive values (90,91% and 100%) but low specificity (28,57% and 40%) for identifying nodular goiter and PTC, respectively. It is concluded that MMP-26 is a promising complementary biomarker for the diagnosis of thyroid tumors, highlighting its participation in the pathogenesis of lesions. However, more research is needed to determine its real impact as a diagnostic and prognostic biomarker.