Nora Hilda Segura-Méndez

Expression of resistin, CXCR3, IP-10, CCR5 and MIP-1α in obese patients with different severity of asthma.

Asthma studies suggest that alteration in the inflammation pattern may be associated with the severity of asthma. The aim of this study was to compare in vitro the expression of chemokines, chemokine receptors and cytokine production from CD4+ T human lymphocytes of asthmatic, both obese and non-obese patients with different severity levels of asthma. Lymphocytes were labeled with monoclonal anti-human CXCR3/IP-10, MIP-1a/CCR5 antibodies and were analyzed by flow cytometry. Cell culture supernatants were used to measure production of interleukin IL-6 and resistin by ELISA. CXCR3/IP-10 expression increased in non-obese patients with mild persistent asthma (2.2%, p<0.05), moderate persistent asthma (3%, p<0.003) and severe persistent asthma (4%, p<0.004); this effect was stronger in obese patients with severe persistent asthma (35%, p<0.004). MIP-1 α / CCR5 increased in non-obese patients with intermittent asthma (0.65%, p<0.05) and severe asthma (1.4%, p<0.03); in obese patients, this expression was greater in intermittent asthma (8%, p<0.05) and severe persistent asthma (12%, p<0.04). Resistin production strongly increased in obese patients with intermittent (976 ng/ml) and severe persistent asthma (795 ng/ml). IL-6 increased in both lean and obese persons; however, the highest value was registered in the group of severe persistent obese asthmatics (992 pg/ml). Obesity per se increased the inflammatory profile of chemokines / cytokines secreted by cells of the blood, increasing the inflammatory status in asthmatic patients. Resistin showed characteristics of a pro-inflammatory cytokine mainly in severely obese asthmatics.

Clinical and mutational features of X-linked agammaglobulinemia in Mexico.

X-linked agammaglobulinemia (XLA) is caused by BTK mutations, patients typically show <2% of peripheral B cells and reduced levels of all immunoglobulins; they suffer from recurrent infections of bacterial origin; however, viral infections, autoimmune-like diseases, and an increased risk of developing gastric cancer are also reported. In this work, we report the BTK mutations and clinical features of 12 patients diagnosed with XLA. Furthermore, a clinical revision is also presented for an additional cohort of previously reported patients with XLA. Four novel mutations were identified, one of these located in the previously reported mutation refractory SH3 domain. Clinical data support previous reports accounting for frequent respiratory, gastrointestinal tract infections and other symptoms such as the occurrence of reactive arthritis in 19.2% of the patients. An equal proportion of patients developed septic arthritis; missense mutations and mutations in SH1, SH2 and PH domains predominated in patients who developed arthritis.

Impaired selective cytokine production by CD4+ T cells in Common Variable Immunodeficiency associated with the absence of memory B cells

Common Variable Immunodeficiency (CVID) is a primary immunodeficiency characterized by B cell dysfunction and decreased serum immunoglobulin. CVID patients are classified by the absence or presence of memory B cells. In addition, T cell defects have been demonstrated in only a proportion of CVID patients. The aim of this study was to evaluate the function of CD4(+) T cells from CVID patients and its association with memory B cells. Patients were classified according to their Freiburg groups: group Ia and Ib, with decreased switched memory B cells (<0.4 of PBL), and group II, with normal B cell subsets. Their T cell function was evaluated after stimulation. We observed normal and even increased CD4(+) T cell proliferation in group Ia (p=0.0277). The proliferation positively correlated with the clinical severity score (r=0.4796). We observed lower levels of IL-17A and IL-10 in group Ia (p=0.0177, 0.0109) and Ib (p=0.0009, 0.0084) patients. Group Ib patients also had low levels of IL-13 and IL-9 (p=0.0169, 0.010). Group II patients had similar cytokine production to that of the controls. BAFFR expression was reduced in groups Ia (p=0.0001) and Ib (p=0.0002) and showed an inverse correlation with the severity score (p=0.0262; r=0.5371). ICOS expression was reduced in group Ia (p=0.0364), and PD-1 was increased in group Ib (p=0.0432) patients. This study shows a selective impairment in cytokine production in group Ia patients, which was more extensive than in group Ib patients. The impairment was associated with BAFFR expression in B cells, with ICOS and PD-1 in T cells and, remarkably, with the absence of memory B cells and with the disease severity. Our results suggest that the evaluation of cytokine expression by T cells in combination with the study of B cell memory could be important for understand the pathogenesis of CVID patients.

Delayed diagnosis in X-linked agammaglobulinemia and its relationship to the occurrence of mutations in BTK non-kinase domains

ABSTRACT Background: X-linked agammaglobulinemia (XLA) is characterized by the absence of immunoglobulin and B cells. Patients suffer from recurrent bacterial infections from early childhood, and require lifelong immunoglobulin replacement therapy. Mutations in BTK (Bruton’s Tyrosine Kinase) are associated with this phenotype. Some patients that present XLA do not show typical clinical symptoms, resulting in delayed diagnosis due to the lack of a severe phenotype. This study presents a report of five XLA patients from four different families and attempts to determine a relationship between delayed diagnosis and the occurrence of BTK mutations. Methods: Samples from patients with antibody deficiency were analyzed to determine BTK expression, immunophenotyping and mutation analysis. Clinical and laboratory data was analyzed and presented for each patient. Results: Most patients presented here showed atypical clinical and laboratory data for XLA, including normal IgM, IgG, or IgA levels. Most patients expressed detectable BTK protein. Sequencing of BTK showed that these patients harbored missense mutations in the pleckstrin homology and Src-homology-2 domains. When it was compared to public databases, BTK sequencing exhibited a new change, along with three other previously reported changes. Conclusions: Delayed diagnosis and atypical manifestations in XLA might be related to mutation type and BTK expression.