Evaluation of T-cell subsets in pregnant women infected with SARS-CoV-2.

OBJECTIVE: Immune responses to SARS-CoV-2 are the main cause of tissue damage in coronavirus disease 2019. However, the pathophysiological mechanism of the disease has not been fully elucidated. The aim of this study was to examine T cell subsets of pregnant women infected with SARS-CoV-2 and evaluate the relationship between the possible differences in trimesters and clinical findings of the disease. MATERIALS AND METHODS: Fifty-six pregnant patients with SARS-CoV-2 and 61 healthy pregnant controls were included in the study. T cell subsets were analyzed by flow cytometry. RESULTS: The CD3+ total T cell (p = 0.006 and p = 0.027) of pregnant patients infected with SARS-CoV-2 in second and third trimesters was found to be lower than in the control group. CD3+CD4+ helper T cell (p = 0.035), Treg (p = 0.001), and Treg/Th17 ratio (p = 0.001) were found to be lower in the third trimester patients infected with SARS-CoV-2 than in the controls. Significant decreases were observed only in the Treg (p = 0.001) and Treg/Th17 ratio (p = 0.001) in the first trimester patients infected with SARS-CoV-2 compared to the controls. When trimesters were compared in terms of T subsets, no difference was found (p > 0.05). CONCLUSION: The CD3+ total T cell (p = 0.001), CD3+CD4+ helper T cell (p = 0.011), Treg (p = 0.001), and Treg/Th17 ratio (p = 0.001) were found to be lower in pregnant women infected with SARS-CoV-2. This difference was associated with the development of pneumonia but not with adverse pregnancy outcomes.

CD3G gene defects in familial autoimmune thyroiditis.

The patients with CD3γ deficiency can present with different clinical findings despite having the same homozygous mutation. We report three new CD3gamma-deficient siblings from a consanguineous family with a combined T-B+NK+ immunodeficiency and their variable clinical and cellular phenotypes despite the same homozygous mutation of the CD3G gene (c.80-1G>C). We also re-evaluate a previously reported non-consanguineous family with two CD3gamma-deficient siblings with the same mutation. The median age at diagnosis was 11 years (14 months-20 years). We found all five patients to display autoimmunity: autoimmune thyroiditis (n = 5), autoimmune haemolytic anaemia (n = 2), immune thrombocytopenia (n = 1), autoimmune hepatitis (n = 1), minimal change nephrotic syndrome (n = 1), vitiligo (n = 1) and positive antinuclear antibodies (n = 3) as well as high IgE (n = 2) and atopic eczema (n = 2). While CD3(+) TCRαß+T cell percentages were low in all patients, only one had lymphopenia and 3 had CD3(+) T cell lymphopenia. Strikingly, we report frequent and multiple autoimmunity in tested heterozygous carriers in both families (n = 6; in 67%), and frequent autoimmunity in family members not available for testing (n = 5, in 80%). The results suggest that CD3G should be studied as a candidate gene for autoimmunity and that CD3gamma deficiency should be considered among other primary immunodeficiencies with predominantly autoimmune manifestations.

Type III bare lymphocyte syndrome associated with a novel RFXAP mutation: a case report.

Type III bare lymphocyte syndrome (BLS) is a severe combined immunodeficiency disease caused by the absence of MHC Class II expression associated with low expression of class I molecules. Here, we report a case with type III BLS who lacked RFXAP (Regulatory factor X-associated protein) expression as a result from a novel mutation introducing a premature stopcodon in DE-region at amino acid 73.

The reliability and validity of Turkish version of Childhood Asthma Control Test.

INTRODUCTION: The reliability and validity of Turkish version of Childhood Asthma Control Test (C-ACT). PURPOSE: The management of asthma is an important as well as difficult issue of physician's daily practice particularly in busy clinical settings. C-ACT was created to identify asthma control levels in children aged 4-11 years. Our aim was to evaluate the reliability, validity and responsiveness of C-ACT in a Turkish sample of children with asthma. METHOD: In this multicenter study, 368 children were enrolled. C-ACT was completed every month by parents and patients who were evaluated in 3 visits within 2 month intervals. At each visit, physicians interpret the control level and decided for the treatment step as established in GINA guidelines. RESULTS: The internal consistency reliability of the Turkish version of C-ACT (C-ACT1 to C-ACT5) was found to be 0.82, 0.83, 0.82, 0.82 and 0.80, respectively (reliability statistics, Cronbach's alpha). Test-retest reliability was 0.71. There was significant correlation between C-ACT and physician's assessment of asthma control at visit 1 (r = 0.65, P < 0.001). CONCLUSIONS: Turkish version of C-ACT is an accurate and reliable tool to evaluate asthma control in children aged 4-11 years. Its widespread use may facilitate appropriate assessment of asthma control and may lead to decrease the number of uncontrolled patients.

B-cell maturation and antibody responses in individuals carrying a mutated CD19 allele.

Homozygous CD19 mutations lead to an antibody deficiency due to disruption of the CD19 complex and consequent impaired signaling by the B-cell antigen receptor. We studied the effects of heterozygous CD19 mutations on peripheral B-cell development and antibody responses in a large family with multiple consanguineous marriages. Sequence analysis of 96 family members revealed 30 carriers of the CD19 mutation. Lymphocyte subset counts were not significantly different between carriers and noncarriers in three different age groups (0-10 years; 11-18 years; adults). B cells of carriers had reduced CD19 and CD21 median expression levels, and had reduced proportions of transitional (0-10 years) and CD5(+) B cells (adults). CD19 carriers did not show clinical signs of immunodeficiency; they were well capable to produce normal serum Ig levels and had normal responses to primary and booster vaccinations. The frequency of mutated Vκ alleles was not affected. Heterozygous loss of CD19 causes some changes in the naive B-cell compartment, but overall in vivo B-cell maturation or humoral immunity is not affected. Many antibody deficiencies are not monogenetic, but likely caused by a combination of multiple genetic variations. Therefore, functional analyses of immune cell function should be carried out to show whether heterozygous mutations contribute to disease.

Vernal keratoconjunctivitis--a rare but serious comorbidity of allergic rhinitis and eustachian tube dysfunction.

OBJECTIVE: To determine the prevalence of symptoms and signs of allergic rhinitis (AR) in children with vernal keratoconjunctivitis (VKC) and evaluate eustachian tube (ET) function using tympanometry. METHODS: The patients underwent an otolaryngological examination and symptoms of rhinorrhoea, nasal obstruction, nasal itching and sneezing were evaluated for the diagnosis of AR. Tympanometry was performed by a middle ear analyzer (Impedance audiometer AZ 26, Interacoustics A/S, Assens, Denmark). Blood samples were collected for determination of peripheral blood eosinophil count (PBEC) and serum total immunoglobulin E (IgE). Allergen sensitivity was also determined by skin prick test. RESULTS: The study included 26 males (96.3%) and 1 female (3.7%) with a mean age of 12.1+/-4.4 years. Eight out of 27 subjects (29.6%) had blood eosinophilia and 11 out of 27 subjects had elevated serum IgE (40.7%). A positive skin prick test was identified for at least one allergen in 40% of patients (10/25 subjects). Symptoms and signs of AR were found in 10 subjects (37%). Median serum IgE level in subjects with AR (262.5 kU/L) was higher than without AR (40.2 kU/L) (p=0.08), whereas there were no differences in PBEC or eosinophilia percentage (p>0.05). Mean middle ear pressures in the right and left ears were -66.4 daPa (range between -268 and 4 daPa) and -57.3 daPa (range between -308 and 0daPa), respectively. The tympanometry results were abnormal in 5 subjects (18.5%) (3 type C and 2 type B tympanogram). Three out of 10 VKC patients with AR (30%) and 2 out of 17 VKC patients without AR (11.8%) had abnormal tympanograms (p=0.33). CONCLUSION: AR is commonly associated with VKC and subjects with AR are almost three times more likely to have ET dysfunction than those without. Therefore, opthalmologists should refer VKC patients to otolaryngologists to delineate associated AR and ET dysfunction. Conversely, patients with OME and/or AR who have persistent allergic eye symptoms may well benefit from opthalmologic evaluation for seasonal allergic conjunctivitis and VKC.

Down syndrome associated with severe combined immunodeficiency: a case report.

An 8-month-old boy was admitted to the hospital because of recurrent bronchopneumonia and gastrointestinal tract infections. On physical examination, he had hypotonia, mental retardation, microcephaly with flat facies, low nasal bridge, small nose, small ears. Laboratory evaluation revealed Down syndrome, lymphopenia, hypogammaglobulinemia, reduced proportions of the peripheral blood lymphocytes with an inverted CD4/CD8 ratio and markedly reduced mitogen response of the lymphocytes. We report here unique case of Down syndrome associated with severe combined immunodeficiency.

Transferrin receptor in proliferation of T lymphocytes in infants with iron deficiency.

The aim of this study was to contribute to clarify the mechanism of cellular immune insufficiency occurring during iron deficiency. We studied the expression of the transferrin receptor (TfR) which is called as CD71, on the surface of T lymphocytes in infants with iron deficiency (with and without anemia). A total of 33 infants, aged between 7 and 26 months were included in this study. These subjects were divided into three groups: (i) latent iron deficiency (LID) (group 1), (ii) iron deficiency anemia (IDA) (group 2), and (iii) healthy infants (group 3). Both CD3 levels and CD71 expression of T lymphocytes were analysed by flow cytometry before and after phytohaemagglutinin (PHA) stimulation. The percentage of CD3(+) lymphocytes in infants with IDA was lower than that in controls after PHA stimulation (mean +/- SD, 48.6 +/-10.5% vs. 70.7 +/-7.8%, P < 0.001). The TfR expression of T lymphocytes (CD3 + CD71%) increased in all three groups after PHA stimulation (P < 0.001). No significant difference was seen among the three groups with respect to CD3 + CD71%. Although there was a reduction in the proliferative capacity of T lymphocytes in infants with IDA, their ability to express transferrin receptor on T-lymphocyte cell surface was normal.