[Immunotyping of lymphocytes in the gastric mucosa of patients infected by H. pylori in two regions with contrast in the risk of developing gastric cancer]. / Inmunotipificación de linfocitos en mucosa gástrica de pacientes infectados por H. pylori en dos regiones geográficas con contraste en el riesgo de desarrollar cáncer gástrico.

Helicobacter pylori (H. pylori) infection involves multiple factors internal and external to the host. Among the internal factors, the immune response plays a fundamental role in the process of antigen presentation, lymphocytic response and cytokine-mediated regulatory response that are directly as sociated with disease progression and prognosis. OBJECTIVE: To compare the immune response in gas tric mucosa of H. pylori infected patients in two regions comparing the risk of developing gastric can cer. PATIENTS AND METHOD: 71 participants with symptoms of dyspepsia were included. The samples for biopsies were collected from different regions of the gastric mucosa; the identification of H. pylori was carried out by culture and polymerase chain reaction (PCR) of the ureA gene. For the characteri zation of the histopathological alterations and the immunophenotyping of lymphocytes, anti-human mouse monoclonal antibodies specific for each antigen were used: T lymphocytes: CD3 and CD8; B lymphocytes: CD20; Natural Killer Cells: CD56; Macrophages: CD68. RESULTS: The prevalence of H. pylori was 83.1%, the predominant types of gastritis were chronic gastritis and multifocal atrophic gastritis with intestinal metaplasia (63.4% and 22.5%, respectively). The cellular response was charac terized mainly by polymorphonuclear lymphocytes and positive anti-CD8 reactivity both in stroma and epithelium. CONCLUSIONS: Multifocal atrophic gastritis was more prevalent in the high-risk region for gastric cancer (GC) while non-atrophic gastritis and the expression of CD3 and CD8 antigens in the foveolar epithelium was higher in the low-risk region.

[Immune response Th1/Th2 to Helicobacter pylori and Helminths in co-infected patients]. / Respuesta inmune Th1/Th2 en pacientes co-infectados con Helicobacter pylori y helmintos.

INTRODUCTION: Inflammation associated with Helicobacter pylori (H. pylori) infection is linked to the development of a gastric precancerous lesion. Helminth infections could influence the pro-inflam matory response to such infection from LTCD4+ Th1 to a less harmful LTCD4+ Th2 response. Ob jective: To characterize the polarization of the LTCD4+ Th2 immune response in co-infected pa tients with H. pylori and helminths from low-risk areas for developing gastric cancer. PATIENTS AND METHOD: We analyzed 63 patients infected by H. pylori (40 adults and 23 children). Through the Multiplex Analysis technology (xMAP), we determined the serum profiles of the interleukins asso ciated with the polarization of the immune response of LTCD4+ Th1 (IL-1Β, INF-γ, TNF-α) as well as the LTCD4+ Th2 (IL-4, IL-10, and IL-13). The ratio between helminths co-infection status in H. pylori-infected patients and the polarization of the immune response mediated by LTCD4+ Th1 and LTCD4+ Th2 was assessed using a Mixed Effects Logistic Regression Model. RESULTS: The frequency of helminths was similar between adults (15%) and children (17%). The polarization of the immu ne response was more prevalent in LTCD4+ Th1. Serum values of interleukins associated with the immune response polarization of LTCD4+ Th1 (IL-1Β, INF-γ, and TNF-α) and LTCD4+ Th2 (IL-4, IL-10, and IL-13) were independent of helminths infection status. CONCLUSION: The prevalence of in testinal parasitic infection was high and the immune response polarization was mainly LTCD4 + Th1.

Respuesta inmune Th1/Th2 en pacientes co-infectados con Helicobacter pylori y helmintos / Immune response Th1/Th2 to Helicobacter pylori and Helminths in co-infected patients

Resumen: Introducción: La inflamación asociada con la infección por Helicobacter pylori (H. pylori) se relaciona con la pro gresión de las lesiones precancerosas gástricas. Las infecciones por helmintos podrían modular la respuesta proinflamatoria a la infección por H. pylori desde un perfil tipo LTCD4+ Th1 hacia una respuesta menos perjudicial tipo LTCD4+ Th2. Objetivo: Caracterizar la polarización de la respuesta inmune tipo LTCD4+ Th1/Th2 de pacientes coinfectados por H. pylori y helmintiasis procedentes de áreas de bajo riego para el desarrollo de cáncer gástrico. Pacientes y Método: Se analizaron 63 pacientes, 40 adultos y 23 niños infectados con H. pylori. La determinación de los perfiles séricos de las interleucinas asociadas con la polarización de la respuesta inmune tipo LTCD4+ Th1 (IL-1Β, INF-γ y TNF-α) y tipo LTCD4+ Th2 (IL-4, IL-10 e IL-13) se realizó con Análisis Multiplex (xMAP). La relación entre el estado de coinfección por helmintos en pacientes infectados con H. pylori y la polarización de la respuesta inmune mediada por LTCD4+ Th1 y LTCD4+ Th2, se estudió con un modelo de regresión logístico de efectos mixtos. Resultados: La frecuencia de helmintos fue similar en adultos (15%) y niños (17%). La polarización de la respuesta inmune fue más prevalente hacia el tipo LTCD4+ Th1. Los valores séricos de las interleucinas asociadas con la polarización de la respuesta inmune tipo LTCD4+ Th1 (IL-1 Β, INF-γ y TNF-α) y tipo LTCD4+ Th2 (IL-4, IL-10 e IL-13) fueron independientes del estado de infestación por helmintos. Conclusión: La prevalencia de infección por parasitismo intestinal fue alta y la polarización de la respuesta inmune fue predominantemente hacia un perfil tipo LTCD4 + Th1.

Abstract: Introduction: Inflammation associated with Helicobacter pylori (H. pylori) infection is linked to the development of a gastric precancerous lesion. Helminth infections could influence the pro-inflam matory response to such infection from LTCD4+ Th1 to a less harmful LTCD4+ Th2 response. Ob jective: To characterize the polarization of the LTCD4+ Th2 immune response in co-infected pa tients with H. pylori and helminths from low-risk areas for developing gastric cancer. Patients and Method: We analyzed 63 patients infected by H. pylori (40 adults and 23 children). Through the Multiplex Analysis technology (xMAP), we determined the serum profiles of the interleukins asso ciated with the polarization of the immune response of LTCD4+ Th1 (IL-1Β, INF-γ, TNF-α) as well as the LTCD4+ Th2 (IL-4, IL-10, and IL-13). The ratio between helminths co-infection status in H. pylori-infected patients and the polarization of the immune response mediated by LTCD4+ Th1 and LTCD4+ Th2 was assessed using a Mixed Effects Logistic Regression Model. Results: The frequency of helminths was similar between adults (15%) and children (17%). The polarization of the immu ne response was more prevalent in LTCD4+ Th1. Serum values of interleukins associated with the immune response polarization of LTCD4+ Th1 (IL-1Β, INF-γ, and TNF-α) and LTCD4+ Th2 (IL-4, IL-10, and IL-13) were independent of helminths infection status. Conclusion: The prevalence of in testinal parasitic infection was high and the immune response polarization was mainly LTCD4 + Th1.

Punctual mutations in 23S rRNA gene of clarithromycin-resistant Helicobacter pylori in Colombian populations.

AIM: To characterize punctual mutations in 23S rRNA gene of clarithromycin-resistant Helicobacter pylori (H. pylori) and determine their association with therapeutic failure. METHODS: PCR products of 23S rRNA gene V domain of 74 H. pylori isolates; 34 resistant to clarithromycin (29 from a low-risk gastric cancer (GC) population: Tumaco-Colombia, and 5 from a high-risk population: Tuquerres-Colombia) and 40 from a susceptible population (28 from Tumaco and 12 from Túquerres) were sequenced using capillary electrophoresis. The concordance between mutations of V domain 23S rRNA gene of H. pylori and therapeutic failure was determined using the Kappa coefficient and McNemar's test was performed to determine the relationship between H. pylori mutations and clarithromycin resistance. RESULTS: 23S rRNA gene from H. pylori was amplified in 56/74 isolates, of which 25 were resistant to clarithromycin (20 from Tumaco and 5 from Túquerres, respectively). In 17 resistant isolates (13 from Tumaco and 4 from Túquerres) the following mutations were found: A1593T1, A1653G2, C1770T, C1954T1, and G1827C in isolates from Tumaco, and A2144G from Túquerres. The mutations T2183C, A2144G and C2196T in H. pylori isolates resistant to clarithromycin from Colombia are reported for the first time. No association between the H. pylori mutations and in vitro clarithromycin resistance was found. However, therapeutic failure of eradication treatment was associated with mutations of 23S rRNA gene in clarithromycin-resistant H. pylori (κ = 0.71). CONCLUSION: The therapeutic failure of eradication treatment in the two populations from Colombia was associated with mutations of the 23S rRNA gene in clarithromycin-resistant H. pylori.

Effect of treatment failure on the CagA EPIYA motif in Helicobacter pylori strains from Colombian subjects.

AIM: To evaluate effect of treatment failure on cagA and vacA genotypes in Helicobacter pylori (H. pylori) isolates from Colombia. METHODS: One hundred and seventy-six participants infected with H. pylori from Colombia were treated during 14 d with the triple-standard therapy. Six weeks later, eradication was evaluated by 13C-Urea breath test. Patients with treatment failure were subjected to endoscopy control; biopsies obtained were used for histopathology and culture. DNA from H. pylori isolates was amplified using primers specific for cagA and vacA genes. The phylogenetic relationships among isolates obtained before and after treatment were established by conglomerate analysis based on random amplified polymorphic DNA (RAPD) fingerprinting. RESULTS: Treatment effectiveness was at 74.6%. Of the participants with treatment failure, 25 accepted subjected to a second endoscopy. Prevalence of post-treatment infection was 64% (16/25) and 40% (10/25) by histology and culture, respectively. Upon comparing the cagA and vacA genotypes found before and after therapy, multiple cagA genotypes (cagA-positive and cagA-negative) were found before treatment; in contrast, cagA-negative genotypes decreased after treatment. vacA s1m1 genotype was highly prevalent in patients before and after therapy. The 3'cagA region was successfully amplified in 95.5% (21/22) of the isolates obtained before and in 81.8% (18/22) of the isolates obtained after treatment. In the isolates obtained from patients with treatment failure, it was found that 72.7% (16/22) presented alterations in the number of EPIYA motifs, compared to isolates found before treatment. CONCLUSION: Unsuccessful treatment limits colonization by low-virulence strains resulting in partial and selective eradication in mixed infections, and acts on the cagA-positive strains inducing genetic rearrangements in cagA variable region that produces a loss or gain of EPIYA repetitions.

Genomic variability of Helicobacter pylori isolates of gastric regions from two Colombian populations.

AIM: To compare the genomic variability and the multiple colonization of Helicobacter pylori (H. pylori) in patients with chronic gastritis from two Colombian populations with contrast in the risk of developing gastric cancer (GC): Túquerres-Nariño (High risk) and Tumaco-Nariño (Low risk). METHODS: Four hundred and nine patients from both genders with dyspeptic symptoms were studied. Seventy-two patients were included in whom H. pylori was isolated from three anatomic regions of the gastric mucosa, (31/206) of the high risk population of GC (Túquerres) and (41/203) of the low risk population of GC (Tumaco). The isolates were genotyped by PCR-RAPD. Genetic diversity between the isolates was evaluated by conglomerates analysis and multiple correspondence analyses. RESULTS: The proportion of virulent genotypes of H. pylori was 99% in Túquerres and 94% in Tumaco. The coefficient of similarity of Nei-Li showed greater genetic diversity among isolates of Túquerres (0.13) than those of Tumaco (0.07). After adjusting by age, gender and type of gastritis, the multiple colonization was 1.7 times more frequent in Túquerres than in Tumaco (P = 0.05). CONCLUSION: In Túquerres, high risk of GC there was a greater probability of multiple colonization by H. pylori. From the analysis of the results of the PCR-RAPD, it was found higher genetic variability in the isolates of H. pylori in the population of high risk for the development of GC.