Basophil activation test: Implementation and standardization between systems and between instruments.

The basophil activation test (BAT) is a good ex vivo alternative for measuring hypersensitivity to an allergen in sensitized patients but still lacks standardization. In this present study, we have implemented one of the systems and proposed inter-systems, inter-instrument standardization. Our method for basophil activation and labeling on whole blood: EDTA in one step using BasoflowEx® and FlowCast® . Setup on Navios and fluorescence targets converted to set up FACSCanto™ instrument. Our results: 1) A CD203c/CD63 (BasoflowEx) method was adapted for EDTA samples and simplified. 2) Final washing and concentration and use of time parameter help acquiring as many basophils as possible, spare acquisition time and noise. 3) The modified method was validated according to ISO15189 with a precision at 5.1% RCV, linearity between 1 and 1/8 of anti-IgE stimulation. Results were very close with CCR3/CD63 system (FlowCast). 4) Standardization, between systems and even between instruments. Mean Fluorescence Intensity targets are proposed using standard beads (Cytocal® ) middle peak: FITC = 19.4; PE = 28.8 on Navios® corresponding to FITC = 4,966; PE = 7,373 for FACSCanto. Data analyzed on common software (Kaluza® ) were very closely correlated. 5) Co-labeling of B cells (CD20+) gives the possibility to monitor a significant drop of basophils under stimulation that could explain some underestimation in case of strong hypersensitivity. In conclusion, BAT would strongly benefit from easy implementation [EDTA, one step stimulation/labeling, wash, full sample analysis over time parameter, B cell relative basophil count] and standardization of instrument settings on MFI targets whatever system or instrument is used. © 2017 International Society for Advancement of Cytometry.

Major influence of CD4 count at the initiation of cART on viral and immunological reservoir constitution in HIV-1 infected patients.

BACKGROUND: A persistent immune activation is observed in gut during HIV-1 infection, which is not completely reversed by a combined antiretroviral therapy (cART). The impact of the time of cART initiation may highly influence the size of the viral reservoir and the ratio of CD4(+)/CD8(+) T cells in the gut. In this study, we analyzed the characteristics of HIV rectal reservoir of long-term treated patients, regarding their blood CD4(+) T cells count at the time of cART initiation. RESULTS: Twenty-four consenting men were enrolled: 9 exhibiting a CD4(+) T cells count >350/mm(3) ("high-level CD4 group") and 15 < 350/mm(3) ("low-level CD4 group") in blood, at the start of cART. An immunophenotypical analysis of T and B cells subpopulations was performed in blood and rectal biopsies. HIV cell-associated DNA loads and qualitative intra-cellular RNA were determined in both compartments. The ratio of CD4(+)/CD8(+) T cells was significantly decreased in the blood but not in the rectum of the "low-level CD4 group" of patients. The alteration in ß7(+) CD4(+) T cells homing was higher in this group and was correlated to a low ratio of CD4(+)/CD8(+) T cells in blood. An initiation of cART in men exhibiting a low-level CD4 count was also associated with an alteration of B cells maturation. HIV blood and gut DNA reservoirs were significantly lower in the "high-level CD4 group" of men. A high HIV DNA level was associated to a detectable intracellular HIV RNA in rectum. CONCLUSIONS: An early initiation of cART could significantly preserve gut immunity and limit the viral reservoir constitution.

Brief Report: A High Rate of ß7+ Gut-Homing Lymphocytes in HIV-Infected Immunological Nonresponders is Associated With Poor CD4 T-Cell Recovery During Suppressive HAART.

OBJECTIVE: Correlation between GALT homing markers on lymphocytes and the low blood CD4 T-cell reconstitution in immunological nonresponders (INRs) has been studied. DESIGN: Thirty-one INRs, 19 immunological responders (IRs), and 12 noninfected controls were enrolled in this study. INRs were defined by an undetectable plasma viral load RNA less than 40 copies per milliliter and CD4 T-cell count <500 cells per cubic milliliter in at least 3 years. METHODS: A complete peripheral and mucosal lymphocyte immunophenotyping was performed on these patients with a focus on the CCR9, CCR6, and α4ß7 gut-homing markers. RESULTS: A highly significant upregulation of α4ß7 on INRs peripheral lymphocytes compared with that of IRs has been observed. This upregulation impacts different lymphocyte subsets namely CD4, CD8, and B lymphocytes. The frequency of ß7 Th17 and Treg cells are increased compared with IRs and healthy controls. The frequency of ß7 CD8 T cells in the blood is negatively correlated with integrated proviral DNA in rectal lymphoid cells in contrast to ß7 CD4 T cells associated with HIV integration. CONCLUSIONS: Alteration of lymphocyte homing abilities would have deleterious effects on GALT reconstitution and could participate to HIV reservoir constitution. These results emphasize the great interest to consider α4ß7-targeted therapy in INR patients to block homing of lymphocytes and/or to directly impair gp120-α4ß7 interactions.

Comparison of Screening Dilution and Automated Reading for Antinuclear Antibody Detection on HEP2 Cells in the Monitoring of Connective Tissue Diseases.

BACKGROUND: Indirect immunofluorescence plays a major role in the detection of antinuclear antibodies (ANAs) and follow-up of their titers in the context of connective tissue diseases. Given the numerous unfavorable features of the conventional manual reading of HEP2 slides (need of time and expert morphologists for the reading, lack of standardization, subjectivity of the interpretation), the biomedical industry has developed automated techniques of slide preparation and microscope reading. METHODS: We collected 49 sera beforehand analyzed by the conventional reading of slides. They were prepared again by QUANTA-Lyser(®) and reanalyzed in four different conditions: two dilutions of screening (1/40 and 1/80), two different systems of analysis, NOVA View(®) automated reading (INOVA Diagnostics), then confirmation by the operator, and conventional manual reading by two different qualified operators. The analysis was realized in blind of the first interpretation and clinical diagnosis. The sera were classified in four groups, on the basis of the results of the first analysis: negative sera (titer < 1/160; 11 patients), low positives (titer at 1/160; 18 patients), moderated positives (titers between 1/320 and 1/640; 10 patients), and strong positives (titers between 1/1,280 and 1/2,560; 10 patients). RESULTS: Among the 49 patients, 13 presented a connective tissue disease including 4 systemic scleroderma (SS), 3 rheumatoid arthritis (RA), 2 Goujerot-Sjogren (GS), 2 systemic lupus erythematosus (SLE), 1 polymyositis (PM), 1 Raynaud's syndrome (RS), and 1 CREST syndrome. One patient presented both an SLE and an SS. Regarding the screening dilution, the 1/40 dilution is less specific than the 1/80 dilution for both the systems of analysis (5.6% vs. 16.7% for the manual reading, and 27.8% vs. 50% for the automated reading). It also generates statistically more false positives (P = 0.037 for the conventional analysis and P = 0.003 for the automated system). The automated NOVA View(®) reading of slides allows a gain in specificity for both dilutions, and also statistically less false positives (P = 0.002 at the 1/40 and P = 0.0006 at the 1/80), and detriment of the sensitivity at the highest dilution (84.6% vs. 92.3% with manual reading). Thus, according to our analysis of 49 sera, the automated NOVA View(®) system of reading of slides at the dilution 1/80 seems to be a successful condition for the detection of ANAs on HEP2 cells, close to the significance (P = 0.067). CONCLUSION: The automated NOVA View(®) reading of slides allows saving time, and an improvement in the standardization. Nevertheless, it requires a confirmation by a qualified operator, to interpret mixed patterns in particular.

A Difficult and Rare Diagnosis of Autoimmune Enteropathy in a Patient Affected by Down Syndrome.

Patients with Down syndrome are more susceptible to autoimmune pathologies, in particular endocrine or digestive diseases such as celiac disease. Autoimmune enteropathy is another form of digestive autoimmune disease, non-gluten-dependant, more often diagnosed in male neonates with immunodysregulation and polyendocrinopathy such as the Immunodysregulation, Polyendocrinopathy, Enteropathy, X-linked syndrome. It also exists in the adult, but this pathology is less known and therefore frequently under-diagnosed. Clinical manifestations are similar to celiac disease, but not improved after a gluten-free diet. Autoimmune enteropathy is frequently associated with other autoimmune diseases, such as thyroiditis, myasthenia gravis, lupus or immune deficiencies, as Common Variable Immunodeficiency. Pathological analysis of intestinal biopsies can frequently distinguish autoimmune enteropathy and celiac disease. Autoimmune enteropathy usually has an important lymphoplasmacytic infiltration of the mucosa and a lack of intraepithelial lymphocytes in the gastrointestinal mucosal surface, while celiac disease usually has a polymorph infiltration of the mucosa and an important intraepithelial lymphocytes infiltration. Nevertheless, the two pathological patterns may overlap. Here we report the first case of a patient with Down syndrome associated to autoimmune enteropathy (initially diagnosed as celiac disease), chronic pancreatitis and cutaneous lupus erythematosus. Even if autoimmune pathologies are much more common in patients with Down syndrome, we would like to report on this rare and original association found in our patient.