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Background: Metabolic syndrome (MetS) is a set of conditions associated with an increased cardiovascular risk. Several serum fatty acids (FAs) seem to play an essential role in the development of cardiometabolic diseases and mortality. Thus, it is imperative to explore the impact of FAs on MetS parameters, using an early MetS screening tool such as MetScore, which is readily available in clinical practice., Aim: The aim of this study was to assess the potential correlation between serum FAs and cardiovascular risk using a MetScore., Methods: This cross-sectional study involved 41 women with severe obesity. The MetScore was calculated, and participants were categorized into high- and low-cardiovascular-risk groups based on the median MetScore value. Gas chromatography was used to quantify serum FAs. Generalized Linear Models were used to compare group means. The association was assessed through simple logistic regression, and an adjusted logistic regression was conducted to validate the association between Metscore and serum FAs., Results: The high-cardiovascular-risk group exhibited elevated values of HOMA-IR, palmitic, oleic, cis-vaccenic, and monounsaturated fatty acids, as well as the SCD-18C, indicating a heightened cardiovascular risk. Conversely, HDL-c, QUICK, gamma-linolenic, and eicosatetraenoic fatty acids showed lower values compared to the low-risk group., Conclusions: Women with severe obesity and high cardiovascular risk have lower values of some omega-3 and omega-6 FAs, considered cardioprotective and anti-inflammatory, and have higher lipogenic activity and FAs, correlated with high cardiovascular risk. These findings emphasize the need to address lipid metabolism in this population as a therapeutic target to reduce cardiovascular risk. Future research should explore clinical interventions that modulate fatty acid metabolism to mitigate cardiometabolic complications.

Background: Inflammation plays a central role in many chronic diseases that characterize modern society. Leptin/adiponectin and adiponectin/leptin ratios have been recognized as notable markers of dysfunctional adipose tissue and, consequently, an inflammatory state. Methods: Blood samples were collected from 41 adult volunteers (40.2 ± 8.3 years) diagnosed with severe obesity (BMI 46.99; 42.98-51.91 kg/m 2 ). The adipokines were quantified using an enzyme-linked immunosorbent assay, while the serum fatty acid analysis was conducted using chromatography. Results: The results unveiled a positive correlation between the leptin/adiponectin ratio and the 20:3n6 fatty acid (r = 0.52, p = 0.001), as well as a similar positive correlation between the adiponectin/leptin ratio and the 22:6n3 fatty acid (r = 0.74, p = 0.001). In the regression analysis, the 22:6n3 fatty acid predicted the adiponectin/leptin ratio (β = 0.76, p < 0.001), whereas C20:3 n-6 was a predictor for inflammatory markers (β = 4.84, p < 0.001). Conclusions: In conclusion, the 22:6n3 fatty acid was demonstrated to be a predictive factor for the adiponectin/leptin ratio and C20:3 n-6 was a predictor for inflammatory markers. This discovery, novel within this population, can help develop new intervention strategies aimed at controlling the inflammatory status in individuals classified as having severe obesity.

Background: The increase in the prevalence of obesity is associated with the increase in the consumption of ultra-processed foods and may be related to the increase in the disorders involving metabolism and the transport and storage of fatty acids., Objective: To evaluate the effect of processed food consumption according to the degree of processing on the serum fatty acid levels and lipid profile of women with severe obesity., Methods: This was a cross-sectional study. Data were collected from anthropometric assessments, the food frequency questionnaire (FFQ), and blood tests for lipidogram studies and serum fatty acid measurements. The foods consumed were identified through the FFQ and classified according to the degree of processing based on the NOVA rating, and the frequencies of consumption were transformed into scores, as proposed by Fornés methodology. Data were analyzed using IBM SPSS Statistics, version 21. The significance level for the analysis was set at 5%., Results: This study included 44 women with a mean age of 40.59 years and mean body mass index of 48.61 kg/m 2 . An inverse association was observed between the consumption of unprocessed and the occurrence of hypertriglyceridemia ( p  = 0.021) and levels of triglycerides ( p  = 0.047), total cholesterol ( p  = 0.030), and very low-density lipoprotein-cholesterol ( p  = 0.039). The consumption of processed foods was positively associated with the presence of hypertriglyceridemia ( p  = 0.044) and omega 6/3 ratio ( p  = 0.001) and negatively associated with total omega 3 levels ( p  = 0.011). The consumption of processed foods was positively associated with total cholesterol ( p  = 0.041) and negatively associated with the omega 3/6 ratio ( p  = 0.001). A negative correlation was found between the average consumption of ultra-processed foods (at least once a week) and serum level of high-density lipoprotein ( p  = 0.035)., Conclusion: The consumption of processed and ultra-processed foods was associated with unfavorable lipid profiles and fatty acid levels in women with severe obesity. These results emphasize the importance of promoting the consumption of unprocessed food to mitigate metabolic disorders linked to processed food intake., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Lopes, Figueiredo, Kattah, Lima, Oliveira, Horst, Oyama, Dâmaso, Whitton, de Souza Abreu, Duarte, Pimentel and Corgosinho.)

Introduction: Microbial systems, such as Escherichia coli , as host recombinant expression is the most versatile and the cheapest system for protein production, however, several obstacles still remain, such as recovery of soluble and functional proteins from inclusion bodies, elimination of lipopolysaccharides (LPS) contamination, incomplete synthesis, degradation by proteases, and the lack of post-translational modifications, which becomes even more complex when comes to membrane proteins, because they are difficult not only to produce but also to keep in solution in its active state. T-cell Immunoglobulin and Mucin domain 3 (TIM-3) is a type I transmembrane protein that is predominantly expressed on the surface of T lymphocytes, natural killer (NK) cells, dendritic cells, and macrophages, playing a role as a negative immune checkpoint receptor. TIM-3 comprises a single ectodomain for interaction with immune system soluble and cellular components, a transmembrane domain, and a cytoplasmic tail, responsible for the binding of signaling and scaffolding molecules. TIM-3 pathway holds potential as a therapeutic target for immunotherapy against tumors, autoimmunity, chronic virus infections, and various malignancies, however, many aspects of the biology of this receptor are still incompletely understood, especially regarding its ligands. Methods: Here we overcome, for the first time, the challenge of the production of active immune checkpoint protein recovered from bacterial cytoplasmic inclusion bodies, being able to obtain an active, and non-glycosylated TIM-3 ectodomain (TIM-3-ECD), which can be used as a tool to better understand the interactions and roles of this immune checkpoint. The TIM-3 refolding was obtained by the association of high pressure and alkaline pH. Results: The purified TIM-3-ECD showed the correct secondary structure and was recognized from anti-TIM-3 structural-dependent antibodies likewise commercial TIM-3-ECD was produced by a mammal cells system. Furthermore, immunofluorescence showed the ability of TIM-3-ECD to bind to the surface of lung cancer A549 cells and to provide an additional boost for the expression of the lymphocyte activation marker CD69 in anti-CD3/CD28 activated human PBMC. Discussion: Taken together these results validated a methodology able to obtain active checkpoint proteins from bacterial inclusion bodies, which will be helpful to further investigate the interactions of this and others not yet explored immune checkpoints., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Lima, Chura-Chambi, Morganti, Silva, Cabral-Piccin, Rocha, Medina, Ramos and Luz.)

Obesity, a complex disease that involves energy imbalance and chronic low-grade inflammation, is implicated in the pathogenesis of several chronic non-communicable diseases. As dietary components modulate the human body's inflammatory status, the Dietary Inflammatory Index (DII ® ), a literature-derived dietary index, was developed in 2009 to characterize the inflammatory potential of a habitual diet. Abundant research has been conducted to investigate the associations between DII and obesity. In this narrative review, we examined the current state of the science regarding the relationships between DII and the inflammatory pathophysiological aspects related to obesity. DII is associated with inflammation in obesity. The most pro-inflammatory diet was directly related to higher levels of pro-inflammatory markers, which included C-reactive protein (CRP), interleukin-6 (IL-6), IL-1β, and tumor necrosis factor-α (TNF-α). Therefore, evidence suggests that the use of the DII may be useful for understanding the relationship between diet and the inflammatory process related to obesity.

In swine production, parasites, especially gastrointestinal helminths, generate considerable economic losses. Therefore, effective control measures, such as the use of the correct anthelmintics, are of paramount importance for maintaining profitability. The aim of the present study was to evaluate the efficacy of the anthelmintic oxibendazole, administered orally, in pigs (non-industrial) naturally infected with gastrointestinal nematodes. To that end, we selected 18 pigs naturally parasitized by gastrointestinal nematodes, as determined by examination of fecal samples (eggs per gram (EPG > 500) of feces), and divided them into two groups: treated (with a 10-day course of oxibendazole) and control (untreated). After the treatment period, the animals were euthanized. During necropsy, the helminths in the gastrointestinal tract were identified and quantified. The species identified were, in order of occurrence, Ascaris suum, Trichuris suis, Oesophagostomum dentatum, and Hyostrongylus rubidus. In Brazilian swine herds, traditional (non-industrial) production systems can favor the transmission of helminths. We found that treatment with oxibendazole was 100% effective against A. suum and H. rubidus, whereas it was 99.65% effective against O. dentatum and 99.20% effective against T. suis, significantly reducing helminth counts (P < 0.01 for all). We conclude that oxibendazole is effective in controlling the main helminths in swine.

Serological testing is a powerful tool in epidemiological studies for understanding viral circulation and assessing the effectiveness of virus control measures, as is the case of SARS-CoV-2, the pathogenic agent of COVID-19. Immunoassays can quantitatively reveal the concentration of antiviral antibodies. The assessment of antiviral antibody titers may provide information on virus exposure, and changes in IgG levels are also indicative of a reduction in viral circulation. In this work, we describe a serological study for the evaluation of antiviral IgG and IgM antibodies and their correlation with antiviral activity. The serological assay for IgG detection used two SARS-CoV-2 proteins as antigens, the nucleocapsid N protein and the 3CL protease. Cross-reactivity tests in animals have shown high selectivity for detection of antiviral antibodies, using both the N and 3CL antigens. Using samples of human serum from individuals previously diagnosed by PCR for COVID-19, we observed high sensitivity of the ELISA assay. Serological results with human samples also suggest that the combination of higher titers of antiviral IgG antibodies to different antigen targets may be associated with greater neutralization activity, which can be enhanced in the presence of antiviral IgM antibodies., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Peroni, Toscaro, Canateli, Tonoli, de Olivera, Benedetti, Coimbra, Pereira, Marques, Proença-Modena, Lima, Viana, Borges, Lin-Wang, Abboud, Gun, Franchini and Bajgelman.)

Immunotherapy explores several strategies to enhance the host immune system's ability to detect and eliminate cancer cells. The use of antibodies that block immunological checkpoints, such as anti-programed death 1/programed death 1 ligand and cytotoxic T-lymphocyte-associated protein 4, is widely recognized to generate a long-lasting antitumor immune response in several types of cancer. Evidence indicates that the elimination of tumors by T cells is the key for tumor control. It is well known that costimulatory and coinhibitory pathways are critical regulators in the activation of T cells. Besides blocking checkpoints inhibitors, the agonistic signaling on costimulatory molecules also plays an important role in T-cell activation and antitumor response. Therefore, molecules driven to costimulatory pathways constitute promising targets in cancer therapy. The costimulation of tumor necrosis factor superfamily receptors on lymphocytes surface may transduce signals that control the survival, proliferation, differentiation, and effector functions of these immune cells. Among the members of the tumor necrosis factor receptor superfamily, there are 4-1BB and OX40. Several clinical studies have been carried out targeting these molecules, with agonist monoclonal antibodies, and preclinical studies exploring their ligands and other experimental approaches. In this review, we discuss functional aspects of 4-1BB and OX40 costimulation, as well as the progress of its application in immunotherapies., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Mascarelli, Rosa, Toscaro, Semionatto, Ruas, Fogagnolo, Lima and Bajgelman.)

Studies involving foods associated with pain reversal and anti-inflammatory effects using zebrafish are rarely reported in the literature. This study aimed to evaluate the effect of graviola ( Annona muricata L.) fruit bar (GFB) and GFB added with acerola ( Malpighia glabra L) seed extract (ASE) on acute nociception and abdominal inflammation in adult zebrafish ( Danio rerio) . Acute nociception was induced by formalin, capsaicin, cinnamaldehyde, acidic saline, glutamate (cutaneous models), and hypertonic saline (corneal model), and inflammation was induced by carrageenan. Both GFB and ASE exhibited antinociceptive effect modulated by the nitrergic system, guanylate cyclase, and transient receptor potential ankyrin 1 and acid-sensing ion channels. The antinociceptive effect of GFB also appears to be modulated by the opioid system and glutamatergic receptors (N-methyl-D-aspartate receptor). Only ASE presented corneal antinociceptive effect. Both samples showed anti-inflammatory effect, being more significant the effect of GFB. The addition of acerola by-product extract in GFB results in a product with greater biological potential.

Grape pomace obtained as a byproduct of industrial processing of grapes retains nutrients and substances with anthelmintic potential such as saponins, tannins, and flavonoids. Therefore, this study evaluated the in vitro ovicidal and larvicidal activity of hydroalcoholic grape pomace extract against gastrointestinal nematodes of sheep. The anthelmintic evaluation was performed by in vitro assays with eggs and larvae of nematodes obtained from naturally infected donor sheep. The grape pomace extract showed high in vitro ovicidal and larvicidal activity with LD 50 values of 0.30 mg/mL for egg hatching inhibition, 1.01 mg/mL for larval development inhibition and 100% efficacy in larval migration inhibition assays at all concentrations evaluated. The effect of tannins was evaluated by the addition of 50 mg/mL polyvinyl polypyrrolidone to grape pomace extract at the concentration of 12.5 mg/mL. The in vitro ovicidal activity of grape pomace was reduced by only 15% after polyvinyl polypyrrolidone addition, indicating that other phytochemicals also contribute to the ovicidal activity displayed by the extract. Our results demonstrate that grape pomace exhibits in vitro anthelmintic activity, suggesting that, beyond its nutritional potential, this pomace can also be an ally for gastrointestinal nematode control in sheep.

No specific therapeutics are available for the treatment of sepsis-induced liver dysfunction, a clinical complication strongly associated with the high mortality rate of septic patients. This study investigated the effect of the essential oil of Hyptis crenata (EOHc), a lamiaceae plant used to treat liver disturbances in Brazilian folk medicine, on liver function during early sepsis. Sepsis was induced by the cecal ligation and puncture (CLP) model. Rats were divided into four groups: Sham, Sham+EOHc, CLP, and CLP+EOHc. EOHc (300 mg/kg) was orally administered 12 and 24 h after surgery. The animals were sacrificed for blood collection and liver tissue samples 48 h after surgery. Hepatic function was evaluated by measuring serum bilirubin, alkaline phosphatase (ALP), aspartate aminotransferase, and alanine aminotransferase (ALT) levels. The levels of malondialdehyde and the activity of superoxide dismutase, catalase, and GSH peroxidase (GSH-Px) were measured for assessment of oxidative stress. Liver morphology was analyzed by hematoxylin and eosin staining. EOHc normalized serum ALP, ALT, and bilirubin levels and inhibited morphological changes. In addition, we observed that EOHc inhibited elevation in hepatic lipid peroxidation and reduction of the glutathione peroxidase activity induced by sepsis. Our data show that EOHc plays a protective effect against liver injury induced by sepsis.

Introduction: Tuberculosis, particularly multi-drug-resistant tuberculosis, is a major cause of morbidity and mortality worldwide. To the best of our knowledge, however, no study to date has assessed the combined use of the four available drugs for tuberculosis treatment, which is an issue of great clinical relevance., Objective: To determine whether the four-drug fixed-dose combination is safer or more effective than separate drugs for treatment of pulmonary tuberculosis., Methods: A systematic review of the literature was performed in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines., Results: In pooled results from five randomized controlled trials with 3502 patients across Africa, Asia, and Latin America, four-drug fixed-dose combination therapy was no better than separate drugs therapy in terms of culture conversion after 2 and 6 months of treatment. There were no significant differences between the groups in overall incidence of adverse effects. However, the meta-analytic measure (log odds ratio) revealed that separate drugs treatment had a 1.65 [exp (0.5)=1.65] increased chance of gastrointestinal adverse effects compared to four-drug fixed-dose combination treatment., Conclusions: The reviewed studies showed that four-drug fixed-dose combination therapy provides greater patient comfort by reducing the number of pills and the incidence of gastrointestinal adverse effects, as well as simplifying pharmaceutical management at all levels., (Copyright © 2016 Sociedade Brasileira de Microbiologia. Published by Elsevier Editora Ltda. All rights reserved.)

Background: Diabetic retinopathy (DR) is the major cause of blindness among working age adults. The aim of the study was to investigate risk factors for development of DR., Methods: A case-control study was performed based on data from 240 individuals (80 cases and 160 controls) attending the Outpatient Specialty Clinic of the University of South Santa Catarina (UNISUL), between Mar/2010 and May/2014. Data collection occurred through review of medical charts for presence or absence of DR, determined by an ophthalmologist. Study protocol included demographic characteristics, metabolic control, diabetes mellitus (DM) profile and comorbidities. Statistical analysis used Chi square test for qualitative variables and multivariate logistic regression analysis to select independent variables (SPSS ® 18.0 software). Odds ratio (OR) was used as measure of association. The study was approved by research ethics committee of UNISUL., Results: Mean age of group case was 59.5 years with a slight female predominance. Gender, age, body mass index were not associated with outcome. Individuals with poor glycemic control were more likely to DR (OR 3.83; 95 % CI 1.57-9.37). It was observed a positive relationship between duration of DM and DR, with higher chances in 11-15 years of disease (OR 7.52, 95 % CI 3.03-18.68) and >15 years (OR 9.01, 95 % CI 3.58-22.66). Regarding comorbidities, only diabetic nephropathy showed higher chance for DR (OR 3.32; 95 % CI 1.62-6.79)., Conclusions: Diabetic patients after 10 years of disease with poor glycemic control and nephropathy have a higher chance of DR.

Objectives: Describe the overweight frequency (overweight and obesity) and identify the factors associated with this in children and adolescents with type 1 diabetes mellitus (T1DM) treated at a University Children's Hospital in Rio de Janeiro., Methods: This is an analytical cross-sectional study, which included patients diagnosed with T1DM who had complete anthropometric data (weight and height) and excluded those using drugs with effect on weight gain, genetic syndromes, celiac disease, hypothyroidism, renal failure and other chronic diseases, and pregnant women. The data collection was referring to the last consultation, and with respect to laboratory tests, the most recent data was collected. The dependent variable was the overweight, defined as Z score ≥1. The independent variables were gender, age, insulin dose, duration of disease, lipid profile, glycated hemoglobin, type of prescribed food planning, and place of residence. A logistic regression model was built for each outcome studied, considering significant associations those with p < 0.05., Results: The study included 195 patients with a mean age of 10.6 (±3.8) years, and 49.7 % (n = 97) aged less than 10 years. The overweight frequency was 40 % (n = 78). The age ≥10 years (OR 0.41; 95 % CI 0.20-0.86; p = 0.019) and the dose of insulin/kg ideal weight (OR 3.38; 95 % CI 1:55-7:39; p = 0.002) were considered the variables associated with overweight., Conclusions: There was a high prevalence of overweight, which explains strategies for promoting healthy eating habits and changing lifestyle with a focus on children and adolescents with diabetes.

Background: Alpha-pinene (α-pinene) is a monoterpene commonly found in essential oils with gastroprotective activity obtained from diverse medicinal plants, including Hyptis species. The genus Hyptis (lamiaceae) consists of almost 400 species widespread in tropical and temperate regions of America. In the north and northeastern Brazil, some Hyptis species are used in traditional medicine to treat gastrointestinal disturbances., Objective: The present study has investigated the gastoprotective effect of purified α-pinene in experimental gastric ulcer induced by ethanol and indomethacin in mice., Materials and Methods: Gastric ulcers were induced in male Swiss mice (20-30 g) by oral administration of absolute ethanol or indomethacin 45 min after oral pretreatment with vehicle, standard control drugs or α-pinene (10, 30, and 100 mg/kg). One hour after the ulcerative challenges, the stomach were removed, and gastric lesions areas measured. The effects of α-pinene on the gastric juice acidity were determined by pylorus ligation model. The gastrointestinal motility and mucus depletion were determined by measuring the gastric levels of phenol red and alcian blue, respectively. Hematoxylin and eosin stained sections of gastric mucosa of the experimental groups were used for histology analysis., Results: α-pinene pretreatment inhibited ethanol-induced gastric lesions, reduced volume and acidity of the gastric juice and increased gastric wall mucus (P < 0.05). Furthermore, we showed an interesting correlation between concentration of α-pinene and gastroprotective effect of Hyptis species (P Pearson = 0.98)., Conclusion: Our data showed that the α-pinene exhibited significant antiulcerogenic activity and a great correlation between concentration of α-pinene and gastroprotective effect of Hyptis species was also observed.

[Purpose] The study analyzed the electroencephalographic (EEG) data of the central cortical areas, during execution of the motor gestures of feeding, activation of the system of mirror neurons, and imagery between a right hemiparetic volunteer (RHV) and a healthy volunteer (HV). [Subjects and Methods] The volunteers' EEG data were recorded with their eyes open for 4 minutes while they performed five experimental tasks. [Results] The alpha band, absolute power value of HV was lower than that of RHV. In the beta band, during the practice condition, there was an increase in the magnitude of the absolute power value of HV at T3, possibly because T3 is representative of secondary motor areas that work with cortical neurons related to planning and organizing sequence of movements performed by the hands. The gamma band is related to the state of preparation for movement and memory. The results of this study indicate that there was increased activation of the gamma frequency band of HV. [Conclusion] The findings of this study have revealed the changes in pattern characteristics of each band which may be associated with the brain injury of the hemiparetic patient.

Staphylococcal food poisoning is one of the most frequent foodborne illnesses worldwide and it is caused by the ingestion of food contaminated with enterotoxins produced by some strains of Staphylococcus (S.) aureus. In the State of Rio Grande do Sul (RS), Southern Brazil, S. aureus has been identified as the second most frequent agent of foodborne illnesses in the last two decades. The aim of the present study was to assess and analyse the epidemiological data of S. aureus food poisoning occurred in the State of RS during the years of 2000 to 2002. The official records of epidemiological investigations carried out by the Sanitary Surveillance Services of the State of RS were analysed. Among foodborne outbreaks for which aetiology was determined, S. aureus was identified as the responsible agent of 57 foodborne outbreaks, being 42 (74%) confirmed by microbiological analyses and 15 (26%) confirmed by clinical symptoms and/or epidemiological data. Staphylococcal outbreaks were responsible for the exposition of 5,991 persons, of which 1,940 (32%) were interviewed by the Sanitary Surveillance officers. The most affected age group corresponded to people with 20 to 49 years old (48%), where men (48%) and women (52%) were affected similarly. The main involved food vehicles were meats servings (35%), followed by pastries (25%), cheese (23%), pasta (11%) and potato salad with homemade mayonnaise (11%). The majority of the outbreaks occurred inside private homes (33%) followed by commercial food establishments (28%). Inadequate control of temperature and failures in general hygiene practices were identified as the main factors responsible for the outbreaks. In conclusion, S. aureus was an important food poisoning etiological agent in the State of RS during 2000 to 2002 and its prevention depends on control measures involving different parts of the food chain.

Allergic bronchopulmonary aspergillosis is a lung disease occurring in patients with asthma or cystic fibrosis, triggered by a hypersensitivity reaction to the presence of Aspergillus fumigatus in the airways. We report herein the case of a patient presenting a clinical profile suggestive of asthma and meeting the clinical, laboratory testing and radiological criteria for a diagnosis of allergic bronchopulmonary aspergillosis. The importance of such findings is that early diagnosis can reduce the risk of respiratory exacerbations and fibrosis.

Since its initial description, the laparoscopic retroperitoneal lymph node dissection has evolved considerably, from a purely diagnostic tool performed to stage germ cell testicular cancer to a therapeutic operation that fully duplicates the open technique. Herein, we describe the current technique employed at our institution, along with illustrations of all surgical steps, and delineate the refinements of the technique over time.

Leishmania major specific murine T cell blasts and clones maintained in vitro were tested for their ability to adoptively transfer delayed type hypersensitivity (DTH) reactions to normal mice. These effector cells exhibited a Lyt 1+2- cell surface phenotype. They induced specific DTH reactions in syngeneic DBA/2 mice after local transfer in the footpad, (together with parasite antigens) or intravenous injection followed by challenge with parasite antigens in the footpad. The DTH reactions were specific for L. major antigens and required H-2 identity between the injected T cells (clones) and the adoptively transferred host. Using radioactively labelled T cell blasts for intravenous transfer, it was demonstrated that a large fraction of these functionally active cells localized in the spleen and footpad which had been challenged with parasite antigens.