Severe combined immunodeficiency with abnormalities in expression of the common leucocyte antigen,CD45

Accepted 16 September 1996
Children presenting with disseminated viral infections should be carefully investigated because they almost invariably have an underlying immunodeficiency. A child is reported who had disseminated cyto-megalovirus and a novel form of severe co-mbined immunodeficiency with abnormal expression of the common leucocyte antigen, CD45.

     

Abnormal cell surface antigen expression in individuals with variant CD45 splicing and histiocytosis

Hemophagocytic lymphohistiocytosis (HLH) and Langerhans cell histiocytosis (LCH) are members of a group of rare heterogenous disorders, the histiocytoses, characterized by uncontrolled accumulation of pleomorphic infiltrates of leukocytes. The etiology of these diseases is mainly unknown. CD45 is a hemopoietic cell specific tyrosine phosphatase essential for antigen receptor mediated signaling in lymphocytes and different patterns of CD45 splicing are associated with distinct functions. Recently a polymorphism (C77G) in exon 4 of CD45 causing abnormal CD45 splicing and a point mutation affecting CD45 dimerization were implicated in multiple sclerosis in humans and lymphoproliferation and autoimmunity in mice respectively. Here we show that two patients with HLH exhibited abnormal CD45 splicing caused by the C77G variant allele, while a further 21 HLH patients have normal CD45. We have also examined 62 LCH patients and found three to have the C77G mutation. Peripheral blood thymus-derived (T) CD8(+) cells from normal individuals carrying the C77G mutation show a significant decrease in the proportion of cells expressing L-selectin and increased frequency of cells with LFA-1(hi) expression. It remains to be established whether C77G is a contributing factor in these histiocytic disorders.     

Severe combined immunodeficiency: A cohort of 40 patients

Severe Combined Immunodeficiency (SCID) consists of a heterogeneous group of genetic disorders characterized by an arrest in T lymphocyte development which is variably associated with an abnormal differentiation of B and NK cells. In order to depict the clinical state of Iranian patients with SCID, records of forty patients were reviewed. Patients were classified based on the flow cytometry data in two groups of B− and B+. In thirty two families (80%) parents were consanguine and in 17 families (50%) there were affected members other than proband. We showed that autosomal forms of SCID might be more frequent due to higher rate of consanguineous marriages. Alongside several infective complications, complicated Bacillus Calmette-Guérin (BCG) vaccination was documented in 18 cases (45%) following the routine vaccination at birth. BCG immunization is still a part of standard vaccination for newborns in developing countries; whereas in communities with a better health condition it could be held for a few months and performed for kids whose immune system sounds intact. We discuss where consanguine mating is common, a test of screening should be run timely. A complete blood count of cord blood could reveal lymphocytopenia at birth; this helps early diagnosis. Genetic consultation would help the families with affected members preventing new SCID offspring.     

Severe combined immunodeficiency in a child with a healthy adenosine deaminase deficient mother

We investigated adenosine deaminase (ADA) deficient severe-combined immunodeficiency (SCID) in an 8-month-old child with ADA deficient mother. The ADA deficiency in the child was unusual in that the thymic histology was normal. In addition, the thymocytes formed E-rosettes with sheep erythrocytes and were stimulated by T-cell mitogens. ADA activity could not be detected in the child's thymocytes. Studies on the family indicated that the father had about one-half of the normal erythrocyte ADA activity. All the family members with detectable ADA activity appeared to have, according to starch gel electrophoresis of erythrocyte lysates, the common ADA-1 phenotype; however, rigorous identification of phenotype was not possible in this study. The mother had less than 1% of normal ADA activity in both erythrocyte and lymphocyte extracts, but her whole peripheral blood lymphocytes demonstrated about 6% of normal activity. Normal concentrations of ATP and small amounts of dATP were found in the mother's erythrocytes. Deoxyadenosine excretion in her urine was elevated and approximately 5-10% of that excreted by individuals with ADA deficient SCID. These studies suggest that low amounts of ADA activity in erythrocytes and blood lymphocytes of certain individuals may be compatible with good immune function and longevity.     

Severe combined immunodeficiency: a cohort of 40 patients.

Severe Combined Immunodeficiency (SCID) consists of a heterogeneous group of genetic disorders characterized by an arrest in T lymphocyte development which is variably associated with an abnormal differentiation of B and NK cells. In order to depict the clinical state of Iranian patients with SCID, records of forty patients were reviewed. Patients were classified based on the flow cytometry data in two groups of B- and B+. In thirty two families (80%) parents were consanguine and in 17 families (50%) there were affected members other than proband. We showed that autosomal forms of SCID might be more frequent due to higher rate of consanguineous marriages. Alongside several infective complications, complicated Bacillus Calmette-Guérin (BCG) vaccination was documented in 18 cases (45%) following the routine vaccination at birth. BCG immunization is still a part of standard vaccination for newborns in developing countries; whereas in communities with a better health condition it could be held for a few months and performed for kids whose immune system sounds intact. We discuss where consanguine mating is common, a test of screening should be run timely. A complete blood count of cord blood could reveal lymphocytopenia at birth; this helps early diagnosis. Genetic consultation would help the families with affected members preventing new SCID offspring.     

Cognitive and behavioral abnormalities in adenosine deaminase deficient severe combined immunodeficiency.

OBJECTIVE: The objective was to evaluate the cognitive, behavioral, and neurodevelopmental function in patients with adenosine deaminase deficient severe combined immunodeficiency (ADA-SCID) and to compare the findings with those of a case control group of patients without ADA-SCID. STUDY DESIGN: Case-matched pairs of patients with ADA-SCID (n = 11) and patients without ADA-SCID who had undergone bone marrow transplantation were recruited. Subjects were assessed by age-appropriate standard tests of intelligence, behavior, and neurodevelopment. RESULTS: Cognitive ability was not significantly different between the 2 groups, but patients with ADA-SCID showed a significant inverse correlation between deoxyadenosinetrisphosphate levels at diagnosis and IQ (P =.048). Behavioral assessment showed that patients with ADA-SCID functioned in the pathologic range on all domains, whereas mean scores for the control group were within normal limits. Behavioral impairment in patients with ADA-SCID also showed a significant positive correlation with age (P =.026). CONCLUSIONS: Cognitive function in ADA deficiency is adversely affected by the severity of metabolic derangement at the time of diagnosis. In addition, patients with ADA-SCID have significant behavioral abnormalities after transplantation. These defects are not due to the transplant procedure but reflect the systemic nature of ADA deficiency. These findings have important implications for future medical and nonmedical management strategies.     

Severe combined immunodeficiency — the experience of the Royal Children's Hospital, Melbourne, 1969–1979

ABSTRACT. Severe combined immune deficiency is a rare disease involving the B and T cell compartments of the immune system. This paper reviews the local experience of nine such patients and relates the findings to those in the literature.
Of the nine patients, three are alive — all having been successfully transplanted with sibling bone marrow. One of the three transplated patients was so lymphopenic prior to transplant that histocompatibility testing could only be performed after transformation of the patient's lymphocytes to a lymphoid cell line using Epstein Barr (EB) virus.     

Transient decrease in the CD45RA expression on T lymphocytes in neonates with fetal distress

To determine the expression of CD45 isoforms on T lymphocytes in neonates with fetal distress and to evaluate its diagnostic accuracy, peripheral blood samples were examined in 53 neonates who were classified into one of three groups: group I: 'control' group (n = 23), group II: 'mild distress' group (n = 15), and group III: 'moderate distress' group (n = 15). The expression of CD3 (mean +/- SD 24.2 +/- 10.1%), CD4 (23.0 +/- 5.7%), and CD45RA (27.3 +/- 9.6%) on total lymphocytes and the expression of CD45RA on CD4+ T lymphocytes (13.7 +/- 4.7%) in group III were significantly lower than in the other two groups 0-3 days after birth. Sensitivity and specificity of the CD45RA expression on CD4+ T lymphocytes for discrimination of group III were calculated as 0.79 and 1.0, respectively, when the cutoff value was 22.7%. The low CD3, CD4, and CD45RA expression returned to normal levels 10 days and more after birth. There were no differences in the CD8 and CD45RO expression between the groups. We conclude that CD4+ T lymphocytes from neonates with fetal distress show a transient decrease in the CD45RA expression without an increase in the CD45RO expression, and, therefore, analysis of the CD45 isoform expression is useful for laboratory evaluation of fetal distress.     

Severe combined immunodeficiency signalized by eosinophilia and lymphopenia in rotavirus infected infants

BACKGROUND: Severe combined immunodeficiency (SCID) is a heterogeneous disease consisting of several different subtypes. Most subtypes present during infancy and without treatment, infections usually lead to early death. Diagnosis of SCID can be difficult as new subtypes are expected to be discovered soon. Late diagnosis is associated with a poorer outcome. Infections like rotavirus enteritis cannot be cleared in children with SCID due to impaired immunity. The aim of our study was to identify clues in children with rotavirus enteritis that aid to diagnose SCID early. PATIENTS AND METHODS: Total white blood counts in a cohort of SCID patients with persistent rotavirus infection at diagnosis (n=18) were compared to total white blood counts in matched control patients without SCID but with rotavirus infection. RESULTS: Relative and absolute lymphopenia and eosinophilia were more common in SCID patients (p<0.005). CONCLUSION: In infants with rotavirus infection, a full blood count should be performed: Eosinophilia and/or lymphopenia raise a high suspicion of SCID.     

Severe gastrointestinal involvement in children with the acquired immunodeficiency syndrome

Five children with the acquired immunodeficiency syndrome (AIDS) and unusual gastrointestinal disease are described. Two children presented with malnutrition, abdominal distention, and diarrhea. One was found to have moderately severe villus atrophy on jejunal biopsy and was initially thought to have celiac disease. Jejunal biopsy from the second child revealed infiltration of the mucosa with acid-fast bacilli-laden macrophages. A third child suffered recurrent abdominal pain, progressive weight loss, diarrhea, and severe gastrointestinal hemorrhage secondary to infection with cytomegalovirus. Pseudomembranous necrotizing jejunitis associated with overgrowth of Klebsiella pneumoniae in the duodenal fluid occurred in one patient. The fifth child presented in the newborn period with Serratia marcescens cholecystitis. Gastrointestinal disease in children with AIDS may be due to idiopathic villus atrophy and bacterial or opportunistic infection.     

High CD4/CD45RO+ and CD8/CD45RO+ frequencies in children with vaccine-modified measles

BACKGROUND: Despite availability and wide vaccine coverage, measles infections still occur especially in developing countries. An outbreak of measles occurred among previously immunized older Ghanaian children who had milder clinical symptoms with measles-specific IgG antibodies that could have been attributed to secondary vaccine failure, suggesting that the infection was vaccine-modified measles (VMM). METHODS: Two-color immunophenotyping of the peripheral blood mononuclear cells was performed at acute, recovery and convalescence phases for 19 VMM patients (mean age 6.2 +/- 3.5 years) using flow cytometry, and compared with that of 20 healthy, sex- and age-matched controls. RESULTS: The results showed a significantly higher memory helper (CD4(+)/CD45RO(+)) cell frequency and increased suppressor cell (CD8(+)/CD45R0(+)) frequency in VMM patients compared to healthy controls. There were no complications and all the patients recovered completely. CONCLUSIONS: These findings show that the mild symptoms in patients with VMM may have correlated with the increase of memory T cells, which is in sharp contrast with previous reports on acute measles infection. This may suggest that the intact immunologic memory cells could have been crucial for the resolution of VMM.     

RSV感染患儿外周血CD_4~*”CD_(45)RO~+CD_(45)RA~+表达变化的研究

目的：探讨下呼吸道感染呼吸道合胞病毒(RSV)患儿外周血辅助性T淋巴细胞(CD4),原始T细胞(CD45RA+),记忆性T细胞(CD45RO+)表达的变化。方法：用单克隆抗体免疫荧光标记,流式细胞仪检测30例RSV下呼吸道感染患儿急性期外周血单个核细胞(PBMCs)CD4+,CD45RA+细胞,其中11例同时检测CD45RO+细胞,同期检测9例年龄、性别无差异的健康儿为对照。结果：RSV下呼吸道感染组患儿CD4为(32.74±10.60)%,明显低于对照组(40.76±6.82)%,2组有显著性差异(P0.05)。结论：RSV感染急性期存在免疫功能紊乱,外周血CD4,CD45RO+下降,而CD45RA+明显增加,这可能是CD45RO+向呼吸道迁移的结果。     

CD27分子在常见变异型免疫缺陷病发病机制中的作用及其临床意义

CD27分子是记忆型B细胞的表面标志,近年来的研究发现,其在B细胞分化发育过程中和常见变异型免疫缺陷病(CVID)的发病机制中都起了重要作用.CVID患者IgD-IgM-CD27+类别转换记忆型B细胞数量降低的发现,以及根据IgD-IgM-CD27+类别转换记忆型B细胞所提出的新的CVID分类方法,对于预测临床并发症及指导治疗有重要意义.     

Severe combined immunodeficiency and adenosine deaminase deficiency: failure of enzyme replacement therapy

A first-born baby boy presented at age 3 months with persistent diarrhoea, failure to thrive, and recurrent bacterial and fungal infections. Severe combined immunodeficiency was demonstrated. A deficiency of adenosine deaminase (ADA) activity was suggested by the presence of extensive skeletal abnormalities, and the ADA activity in erythrocyte and leucocyte lysates was < 0.005 nmol/h per mg protein. Culture of ADA-negative peripheral blood mononuclear cells, together with purified calf ADA, did not alter the absent phytohaemagglutinin response. Treatment with immunoglobulin, pentamidine, and co-trimoxazole was started and a programme of ADA enzyme replacement, with infusions of plasma and frozen irradiated erythrocytes, was begun at age 4 months and achieved blood ADA levels in excess of 30 nmol/h per mg haemoglobin. Although resolution of the interstitial pneumonitis and skeletal abnormalities was observed, there was no evidence of immunological reconstitution. The patient died at age 17 months after a parainfluenza pneumonitis. Features of importance in predicting lack of benefit from enzyme replacement by erythrocyte infusion in ADA-negative severe combined immunodeficiency appear to be early clinical presentation with associated severe skeletal abnormalities, a very low level of residual ADA activity in peripheral blood mononuclear cells, and lack of effect of exogenous ADA on the absent in vitro mitogen response of ADA-negative blood mononuclear cells.     

D4+T淋巴细胞表面CD4+CD45RA和CD4+CD45RO在支气管哮喘患儿外周血中的表达

目的 探讨CD4 CD45RA和CD4 CD45RO分子在支气管哮喘患儿中的表达及其意义.方法 分别收集支气管哮喘发作期28例、支气管哮喘缓解期27例、健康对照儿童20例抗凝静脉血100μL,采用异硫氰酸荧光素(FITC)标记的抗CD4单抗、藻红蛋白(PE)标记的抗CD45RA单抗和PE-菁蓝色素荧光素(PE-Cy5)标记的抗CD45RO单抗,流式细胞仪检测各组儿童外周血CD4T淋巴细胞表面CD45RA和CD45RO的表达.采用SPSS13.0软件进行统计学分析.结果 与健康对照和支气管哮喘缓解组患儿比较,支气管哮喘发作组患儿CD4 CD45RA T细胞明显减少(q=12.47,8.39 Pa<0.05),CD4 CD45RO T细胞显著升高(q=9.50,8.30 Pa<0.05),CD4 CD45RA /CD4 CD45RO 细胞比值显著降低(q=8.96,6.21 Pa<0.05);支气管哮喘缓解组患儿CD4 CD45RA T细胞较健康对照组明显升高(q=3.08 P<0.05),CD4 CD45RO T细胞及CD4 CD45RA /CD4 CD45RO 细胞比值与健康对照组比较差异无显著性(q=0.45,2.02 Pa>0.05).结论 外周血CD4 CD45RA 和CD4 CD45RO T淋巴细胞平衡失调可能参与支气管哮喘的发病.