These findings highlighted the possibility of paracrine production of 1,25-dihydroxyvitamin D3 production in the CNS. The glial cell expression of the 25(OH)D3 24-hydroxylase gene, CYP24A1, producing the enzyme needed to inactivate calcitriol, suggested further control of 1,25-dihydroxyvitamin D3 levels in the CNS [10]. In a rodent model, Staurosporine manufacturer Spach and Hayes varied the plasma 25-OHD level by varying dietary vitamin D3 and reported that CNS calcitriol correlated with plasma 25-OHD but not with plasma calcitriol [11]. These data provided evidence for calcitriol synthesis in situ in the CNS. Therefore, the presence of 25-hydroxylase and 1-α-hydroxylase

required to synthesize 1,25-dihydroxyvitamin D3 and 24-hydroxylase needed

to degrade 25-hydroxyvitamin D3 and 1,25-dihydroxyvitamin D3 in the brain, along with evidence of in situ CNS calcitriol synthesis, consolidated the idea that the CNS is poised to locally metabolize (and regulate) the active form of vitamin D implicating the importance of this active hormone in brain health and disease. Calcitriol exerts its nuclear effect via the vitamin D receptor (VDR). The discovery of the VDR (mRNA and protein) throughout the brain and spinal cord consolidated the importance of this hormone in modulating nervous system function. Studies from adult rats and hamsters provided a detailed topography of the distribution of VDR in the CNS [2, 3], later shown to Opaganib datasheet be similar in humans [8, 12] (see Figure 2). VDR expression was noted in both neurones and triclocarban glial cells (microglia, astrocytes, oligodendrocytes) in different CNS regions,

including: (i) cortex [temporal (that is, auditory, olfactory, entorhinal), frontal (that is, prefrontal, orbitofrontal, primary motor), parietal, cingulated]; (ii) deep grey matter (thalamus, basal ganglia, hypothalamus, hippocampus, amygdala); (iii) cerebellum (granular and Purkinje cell layers); (iv) brainstem nuclei; (v) spinal cord (anterior horn cells); and (vi) ventricular system (that is, choroid plexus ependymal cells) [13, 14]. VDRs have also been reported in the nuclei of Schwann cells and in peripheral neurones [15, 16]. The VDR is a member of the steroid/thyroid hormone superfamily of transcription regulation factors. On binding of calicitriol, VDR heterodimerizes with the retinoid X receptor (RXR), and subsequently binds specific genomic sequences known as vitamin D response elements (VDREs) to influence gene transcription [17]. Recent construction of a genome-wide map of VDR binding provided evidence of enrichment of VDR-binding sites near autoimmune and cancer-associated genes identified from genome-wide association studies [17] (Figure 3).

These findings indicate that continued malaria infections Idasanutlin solubility dmso are required to maintain antibody titres in an area of intense malaria transmission. Inhabitants of areas with stable malaria transmission develop clinical and parasitological immunity after repeated exposure to Plasmodium falciparum. In areas exposed to intense malaria transmission, protection against severe life-threatening malaria is acquired early in

life after relatively few malaria episodes [1] while protection against mild malaria or asymptomatic infection develops later in life [2, 3]. Despite many years of research on this topic, it is unclear which antibodies are associated with protection and how their development is influenced by natural exposure. A major problem in the interpretation of field studies is that antibody responses are related to both protection and exposure. While protection against clinical malaria episodes is associated with the breadth and magnitude of antibody responses [4], these antibodies are acquired after exposure to blood-stage infections; individual variation in antibody repertoires and titres therefore also reflects individual variations in malaria exposure [5-7]. As cumulative malaria exposure may reduce susceptibility to clinical disease through mechanisms unrelated to the antibodies

being studied, interpretation of findings from cross-sectional and even longitudinal studies [8] is complicated and likely explains why antibodies to specific malaria antigens have inconsistent selleck screening library associations with protection and risk of clinical malaria [7, 9-11]. As expected, the prevalence and/or titre of antibodies is consistently higher in individuals who have microscopically buy Staurosporine detectable parasites at the time of sampling compared with parasite-free individuals [6, 12]. Similarly, individuals with submicroscopic infections may have higher antibody prevalences and titres compared with parasite-free individuals [13]. These associations are sometimes interpreted as evidence for immune boosting by recent infection. It is, however, unclear to what extent these associations are explained by the current infection

or by historic differences in exposure, because individuals who are parasitaemic at the time of sampling may simply have had a higher cumulative antigen exposure [7]. The aim of this study was to examine the effect of malaria infection patterns on malaria-specific antibody acquisition and dynamics in an all-age cohort exposed to intense malaria transmission. For this purpose, we determined antibody prevalence and titre against a selection of three blood stages, one sporozoite and one mosquito salivary antigen at three time points. The study was conducted in 2010 in the Abedi parish in Apac district, northern Uganda, a rural area situated between Lake Kyoga and the Victoria Nile (latitude 1·985; longitude 32·535).

This disparity could be attributed to lack of sensitivity with the assays or related Olaparib supplier to the timing of blood collection, disease progression or other unknown factors causing an immune response in the host. However, as for IgG levels, measurement of total serum IgE appears to be of no benefit in the preliminary clinical investigation into a suspected host. Conversely, dramatic increases in total IgE levels have been documented for crusted scabies (4,27,33,34). Roberts et al. (3) document 96% of 52 cases with elevated IgE, with 73% 10× above normal levels, and 10% 100× above normal levels. Immunoblotting studies demonstrated that sera from patients

with crusted scabies showed strong IgE binding to 21 unidentified S. scabiei var. canis proteins in comparison with ordinary scabies in which only six proteins were weakly recognized (35). Studies using S. scabiei

var. canis whole mite extract to measure scabies-specific IgE binding observed elevated levels in approximately 50% of patients with active ordinary scabies (36). Recent serology results using S. scabiei var hominis recombinant proteins indicate patients with both crusted scabies and ordinary scabies have a defined IgE and IgG4 response to a number of scabies mite recombinant antigens (Walton S.F., unpublished data). Significantly greater IgE binding to a number of these proteins was observed in the sera of patients with crusted scabies compared with ordinary scabies and control groups, and similarly significantly see more increased IgE binding of the sera of patient with ordinary scabies was observed compared with control sera. Immunohistochemistry for staining of mite-infested skin biopsies from patients with crusted scabies has shown human IgG and IgE localizing in the mite gut and flooding the mite burrow (37) (Walton S.F., unpublished data).

In addition, polyclonal antibody to multiple S. scabiei var. hominis recombinant proteins has been demonstrated binding to the gut, external cuticle and burrow of the scabies mite (9,38) (Walton S.F., unpublished data). Immediate wheal reactions have been elicited by intradermal injection of scabies mite extracts in patients with both ordinary scabies and crusted scabies but not normal volunteers (39,40). This response was observed to wane with time, and patients injected 15–24 months after infestation did not react. IgE antibody to allergens induces early allergen-specific mast cell degranulation and contributes to the late-phase reactions by chronic tissue damage via the downstream effect of mast cell mediators and by facilitating allergen presentation to T cells. Mast cell activation also leads to the recruitment and activation of basophils and eosinophils, both of which express the Fc receptor on their surface and can therefore contribute to the IgE-mediated immune response.

Mice were housed and bred in the Biomedical Research Facility at University of North Dakota. All the animal procedures have been approved by the UND IACUC committee. K. pneumoniae (ATCC 43816 serotype II) was provided by Dr. V. Miller (Washington University, St. Louis) [[41]]. Bacteria were grown overnight in LB broth at 37°C with shaking. The bacteria were pelleted by centrifugation at 5000 × g. We then anesthetized mice with 45 mg/kg ketamine and intranasally instilled 2 × 105 colony-forming units (CFUs) of K. pneumoniae in

PBS (50 μl). BAL was performed 5 times with 1.0 mL volumes of lavage fluid, while the first 0.5 mL was saved separately for cytokine detection. A cell smear was made from PR-171 order see more the BAL fluid and stained with HEMA-3 (Fisher, Rockford, IL) for cell differential counting. AMs were collected

from the BAL fluid precipitate after centrifuging at 2000 × g for 5 min at 4°C and cultivated in RPMI 1640 medium supplemented with 10% newborn calf serum and penicillin/streptomycin in a 5% CO2 incubator. After BAL procedures, the lung, liver, and kidneys were aseptically harvested for homogenization or fixed in 10% formalin or OCT [[42]]. For evaluating bacterial burdens in BAL AMs, and lung tissue, BAL was performed to get rid of the free bacteria. Homogenization of lung tissue was done using liquid nitrogen and samples kept on dry ice before dissolving in RIPA buffer for western blotting analysis or in PBS for CFU and superoxide analysis. For western blotting, the samples were sonicated for three times at 10 s each. Histology slides were made after formalin fixation, and stained with the standard hematoxylin-eosin method [[43]]. For immunohistochemistry assays, we performed OCT fixation and cryosection and stained the slides using the methods described previously [[44]]. AMs were resuspended in lysis solution. Lung or other tissues were homogenized by pestle/mortar in liquid nitrogen and followed

by brief sonication. AMs from BAL fluid or homogenized tissues of the lung, liver, and kidneys were spread on LB plates to enumerate the bacteria that have invaded into AMs or tissues. Free bacteria were killed with polymycin B (200 μg/mL) for 1 h and washed away by lavage. Selected unlavaged ADP ribosylation factor samples were also saved and assessed to evaluate the differences in cell signaling. The plates were cultured in a 37°C incubator for 18 h, and bacterial colonies were counted [[22]]. Triplicates were done for each sample and control. Cytokine concentrations in BAL fluids (the first 0.5 mL lavage solution) or tissues were measured by standard ELISA kits according to the manufacturer’s instructions (eBioscience company, San Diego, CA) [[45]]. To overcome detection limits (5 pg/mL), we have only used the initial 0.5 mL of lavage solution to determining cytokine concentrations.

A further limitation to the LCM is that genes expressed in both, FDC and B cells, such as Cd21 cannot be identified by this approach and are therefore missing from selleck chemicals llc the set of genes defined as FDC expressed. The gene expression profile showed that FDC express various extracellular matrix proteins (Fig. 3), known to control the availability of cytokines, chemokines and growth factors 29–31. Indeed, by expressing collagens and fibronectin essential for assembling conduits, FDC may help to regulate the transport of low-molecular-weight proteins 32. The pericellular

localization of biglycan (Fig 4A) is in line with the notion that biglycan functions as an extracellular regulator of cytokines and growth factors 29, 30. Beyond this, FDC may contribute to the mobility of B cells in the GC. Thus, two-photon microscopy has Ensartinib concentration shown that fibroblastic reticular cells guide the migration of T cell through the T-cell zone 33 and FDC may regulate B-cell motility in a similar way 34, 35. As shown for adhesion molecules such as Vcam-1

and Madcam-1, upregulation of the extracellular proteins Periostin and Coch may also ensure a tight association of B cells with FDC during the GC reaction (Fig. 2B) 2, 36, 37. A more global function of regulating lymphocyte migration within the immune compartments involves sphingosine-1-phosphate (S1P) 38. However, expression of S1P-generating sphingosin-lipases was not detected in FDC networks (no “present” calls) nor in any other compartment of the spleen 39. Instead, our analyses showed that stromal cells in the B-cell follicle express Enpp2 an ectoenzyme that hydrolyzes both lysophosphatidylcholine and sphingosinphosphorylcholine (Fig. 2A) 40. It is most likely that FDC control S1P-mediated egress of lymphocytes from the spleen. Altogether, these findings emphasize that antigen presentation by FDC is only one of the many functions in B-cell

development. Defining a new set of genes specifically expressed in FDC allows us to determine different developmental stages of stromal cell differentiation. In the absence Amobarbital of LTα, only weak expression of CXCL13 defines the area where B cells localize (Fig. 4H and Table 1). In CXCR5-deficient mice, LTα is expressed but in the absence of the LTα/CXCL13 feedback-loop the level of LTα is not sufficient for normal development of follicular structures and differentiation of reticular cells into mature FDC 26, 27. Nonetheless, the CXCL13+ stromal cells upregulate the FDC genes BP3, Enpp2 and Bgn (Fig. 4C and G, Table 1). In the SCID mouse, although lymphocytes are missing, the stromal cell compartment does segregate into a BP3hi Bgnhi and a BP3lo Bgnlo area (Fig. 4B). Indeed, with the exception of Serpina1, all of the analyzed FDC genes are expressed also in BP3hi stromal cells, although in most cases at a lower expression level (Fig. 3 and Table 1).

The epidermis

also contains some immune cells, including Langerhans cells and CD8+ T cells, while the underlying dermis exhibits a more complicated histology due to the presence of a variety of immune cells, such as CD4+ Th cells, MΦs, and DC, in addition to fibroblasts 1. CD4+ Th cells can be classified into at least four subsets: Th1, Th2, Th17, and Treg, which coordinate immunity Crizotinib cost by producing unique sets of cytokines 2, 3. They are derived from naïve CD4+ T cells through exposure to specific cytokines and antigen presentation by DC 1, 3. IFN-γ and IL-4 promote the development of Th1 and Th2 cells, respectively, and Th1 and Th2 cells produce IFN-γ and IL-4, respectively, as their signature cytokines. On the other hand, Th17 cells are derived in the presence of TGF-β plus IL-6 for mice or TGF-β plus IL-21 for humans and produce IL-17 3, 4. They also produce IL-22 when

stimulated with IL-23 4. High concentration of TGF-β results in induction of the transcription factor Foxp3 and promotes the development of Treg, BMN 673 ic50 which negatively regulate immune responses through production of IL-10 3, 5. Deregulated cytokine production in the skin leads to inflammatory diseases exemplified by psoriasis and atopic dermatitis in humans, which are T-cell-mediated skin diseases with unknown origin 6, 7. Cytokines derived from Th1 and Th17 cells are implicated in the pathogenesis of psoriasis, while those from Th2 cells are implicated in the pathogenesis of atopic dermatitis 8, 9. Moreover, cytokines derived from keratinocytes are recognized to have an important pathogenic role. For

instance, IL-23 is highly produced by epidermal keratinocytes as well as by Langerhans cells, dermal DC, and MΦs 10, and is implicated in the pathogenesis of psoriasis 1, 7. In addition, keratinocytes release not only chemokines exemplified by CC chemokine ligand (CCL)-20, a chemoattractant for DC precursors 11, but also a large amount of peptides exemplified by LL-37 12 and S100A7 (also known as psoriasin) 13, which are implicated click here in the pathogenesis of psoriasis. Phosphoinositide-specific phospholipase C (PLC) catalyzes the hydrolysis of phosphatidylinositol 4,5-bisphosphate into two vital second messengers, diacylglycerol and inositol 1,4,5-trisphosphate, thereby playing a pivotal role in intracellular signaling. There are six families of mammalian PLC isoforms (β, γ, δ, ε, ζ,and η) 14. PLCε was first identified by others and us as a direct downstream effector of Ras family small GTPases: Ras, Rap1, and Rap2 14, 15. In the skin, PLCε is expressed in resident skin cells but not in leukocytes 16–18. By using PLCε−/− mice, in which PLCε was inactivated by gene targeting, we showed that PLCε plays a crucial role in cutaneous carcinogenesis and inflammation.

Cells were harvested and proliferation and secreted cytokines analysed as described Selleck EPZ6438 previously. Proteins were immobilized on the beads, as per the manufacturer’s instructions. Briefly, 0·5 ml of the provided Dynabeads were washed twice with phosphate-buffered saline (PBS), resuspended in 200 µl of PBS per tube, and 20 µg of anti-CD3ε and/or the indicated µg amount of anti-BTLA test antibody (or antibodies) reagent was absorbed passively to the beads, mixed well and incubated at room temperature for 60 min. The tube was vortexed (bench top) every 3 min to ensure

mixing. Then 100 µl of a 0·5% bovine serum albumin (BSA) solution in PBS was added to each tube and the volume adjusted to 500 µl with PBS to block any unoccupied bead surface. The beads were incubated at 4°C for

3 days with shaking and then washed three times with 0·1% BSA in PBS buffer. They were finally resuspended in 500 µl of 0·1% BSA in PBS to yield a final bead concentration of 4 × 108/ml and the final bead : cell ratio in the well was adjusted to 1:1. For the mixed lymphocyte reaction (MLR) in vitro assay, T cells Selleckchem BMN 673 were isolated from the spleens of C57BL/6 mice with a pan T cell-negative selection isolation kit (Miltenyi Biotech); antigen-presenting cells (APC) were selected negatively from the spleens of BALB/c mice (Miltenyi Biotech). The APC were incubated with mitomycin C (Sigma) at 25 µg/ml for 30 min at 37°C and then washed three times. T cells were cultured with mitomycin C-treated APC at a 1:1 ratio, with 2 × 105 cells per well in 200 µl volume for 5 days. For the last 16 h, 1 µCi of [3H]-thymidine (MP Biomedicals, Inc., Irvine, CA, USA) was added to each well. The cells were then harvested and [3H]-incorporation measured using a 1450 Microbeta Liquid Scintillation and Luminescence Counter Protein kinase N1 (Perkin Elmer, Sherton, CT, USA). For the ovalbumin (OVA) antigen-specific T cell proliferation in vitro assay, CD4 T cells were isolated from the spleens of DO11.10 mice by CD4 T cell-negative selection (Miltenyi Biotec) and APCs were isolated from same mice with an AutoMACS T cell depletion

kit (Miltenyi Biotec). The APCs were incubated with mitomycin C at 25 µg/ml for 30 min at 37°C and then washed three times. The T cells were stimulated by 0·1 µg/ml OVA peptide in the presence of mitomycin C-treated APC at a 1:1 ratio, with 2 × 105 cells per well in a 200 µl volume. Cell proliferation was measured at day 3 as described above. Mouse B cells were purified from C57BL/6 mouse splenocytes by AutoMACS-negative selection (Miltenyi Biotec) and 100 000 cells were incubated in duplicate in 96-well flat-bottomed plates in RPMI-1640 (Invitrogen, Inc.) with 10% heat-inactivated fetal bovine serum (FBS) (54°C for 45 min), 1 mM HEPES and 55 µM β-mercaptoethanol (all from Gibco). Cells were stimulated with 2 µg/ml of lipopolysaccaride (List Biological Laboratories, Inc.

However, of all the Vβ subpopulations analysed, three (Vβ 5·2, 11 and 24) displayed a significantly higher frequency of TNF-α-producing cells compared to all but one of the other Vβ (that defined by Vβ 12) subpopulations (Fig. 5a). The same general profile was seen for the frequency of cells expressing

IFN-γ, with T cells expressing Vβ 5·2, 11 and 24 also having a higher commitment to IFN-γ production compared to at least four other Vβ families (Fig. 5b). In order were Vβ 5·2 (greater than Vβ 2, 5·1, 8 and 17), followed by Vβ 11 and 24 (greater than Vβ 2, 5·1, 8 and 17). Finally, given that our earlier published studies have shown a consistent co-production of IL-10 together with IFN-γ and TNF-α[1], Histone Methyltransferase inhibitor we analysed the frequency of IL-10-producing cells among the same Vβ subpopulations (Fig. 5c). Again, the same Birinapant ic50 Vβ-expressing CD4+ T cells (Vβ 5·2, 11 and 24) displayed a higher frequency of antigen-induced

IL-10-producing T cells than at least four of the other Vβ-expressing T cells. In order were Vβ 5·2 (greater than Vβ 2, 5·1, 8 and 17), followed by Vβ 11 and 24 (greater than Vβ 2, 3, 5·1, 8, 12 and 17). In all cases we reported only Vβ subpopulations that displayed a significantly higher percentage of cells through analysis of all pairs using the Tukey–Kramer anova test. Thus, these results suggest a disproportionate role for a group of CD4+ T cells expressing nearly Vβ 5·2, 11 and 24 that are highly committed to the response against Leishmania, and express cytokine and activation profiles consistent with a regulated, yet activated T cell response. To investigate the possibility that specific subpopulations of CD4+ T cells defined by Vβ expression were involved in the formation of the co-regulated cytokine response among T cells producing IFN-γ and TNF-α,

as we demonstrated for the total CD4+ T cell population in an earlier publication [10], we performed a correlation analysis between the frequency of specific CD4+ Vβ-expressing T cells producing IFN-γ or TNF-α with one another following SLA stimulation. Of the three Vβ subpopulations that showed a higher SLA-specific production of IFN-γ and TNF-α compared to the other Vβ subpopulations, both CD4+ T cells expressing Vβ 5·2 and 11, but not Vβ 24, showed a positive correlation between the frequency of T cells expressing TNF-α and IFN-γ (Fig. 6a and b). Of all the subpopulations analysed, in addition to these two subpopulations, only T cells expressing Vβ regions 8 and 17 also had this correlation (Fig. 6c and d). Interestingly, Vβ 17-expressing cells, despite showing an expansion following SLA stimulation in CL patients, did not display higher frequency of activated or cytokine-producing cells compared to the other subpopulations.

GC-B cells stimulated FDCs to enhance the expression of the cytokines and the adhesion molecules as much as TNF-α did (Fig. 4a). The enhanced secretion of IL-6 and IL-8 and elevated surface expression of ICAM-1 by TNF-α treatment in our experiment (Fig. 4a) is consistent with previous reports.51,52 In addition, GC-B cells can induce secretion of IL-16 and CCL22, which were not increased by the TNF-α. This suggests that GC-B cells produced more factors stimulating the FDCs other than TNF-α. Together, the results in Fig. 4(a) indicate

that our co-culture system is a useful in vitro model to investigate the function of FDCs. The second purpose is to ensure that the change of IL-15 blocking originated from FDC not from GC-B cells. The co-culture experiment

has its own limitations. BMS-777607 datasheet Testing anti-IL-15 can affect stimulator GC-B cells not only FDCs, resulting in the alteration of cytokine profiles in the check details culture supernatant as the result of contaminating GC-B cell factors, and because of FDC factor consumption by GC-B cells. We can determine the exclusive effect of the change of the cytokine profile of IL-15 on FDC in the co-culture experiment by comparing the result with that of the TNF-α set because FDC is the only cellular component in the TNF-α set. For this reason, we only included the secreted factors augmented by both GC-B co-culture and TNF-α addition for the analysis in Fig. 4(b,c). In Fig. 4(b), we suggest that IL-15 signalling is necessary for the increased production of some chemokines. However, it is not definite whether IL-15 alone is sufficient to the increased production of those cytokines. Interleukin-15 can be a co-factor of GC-B-cell factors because there are other GC-B-cell factors including TNF-α in our co-culture experiments. Alternatively, increased amounts of surface IL-15 per se can be sufficient for augmented production of the cytokines because IL-15 expression on the surface of FDCs is increased remarkably upon co-culturing with GC-B cells or addition of TNF-α.13 The effect of IL-15 blocking without GC-B-cell factors cannot be determined

effectively in our system because very low or undetectable amounts of cytokines Reverse transcriptase are produced in cultured FDCs without stimulation. Interestingly, the altered production of CCL-2, CCL-5 and CXCL-8 by blocking of IL-15 signalling corresponds well with findings from earlier studies, which reported that IL-15 increased production of these chemokines from human T cells and monocytes.59,60 There are also reports that IL-15 is a potent inducer of chemokines involved in chemotaxis in other cellular systems.25,61–63 Further investigation of the functional roles of these chemokines produced by FDCs with IL-15 may provide important clues regarding development of the GC reaction. Protective immune responses against an invading pathogen are a race against time.

interactive-biosoftware.com). Primers and PCR conditions

were shown in Table 2. Sequence data were analysed using Sequencher version 5.0 (Gene Codes Corporation, Ann Arbour, MI, USA). Mutations found in the patients were confirmed by direct sequencing of the genomic DNA using a set of primers and parameters according to their mutation sites. Identified mutations were confirmed by direct sequencing in the opposite direction. The available parents were also tested for the identified mutation by PCR-sequencing. The nucleotide position is in accordance with the WASP mRNA (Genbank Accession No. NM_000377). All patients had clinical features consistent with the classic WAS, including thrombocytopenia with small-sized platelets, recurrent infections and eczema. The patients’

age of onset ranged from 6 days to 8 months. Bleeding was the first manifestation in the majority of https://www.selleckchem.com/screening/kinase-inhibitor-library.html cases (85.7%, 6/7 cases) in which bloody stool was the most frequent presenting symptoms (71.4%, 5/7 cases). One patient was initially presented with pneumonia and hepatosplenomegaly. Cytomegalovirus (CMV) infection was subsequently confirmed. Of all the patients with recurrent infections, pneumonia was the most commonly found (85.7%, 6/7 cases). Other infections included central nervous system infections, infective diarrhoea caused by Salmonella, otitis media, sepsis and perianal abscess. The patients’ clinical features are summarized in Table 1. Immunoglobulin Atezolizumab levels and lymphocyte subsets were evaluated in all patients (Table 3). Of these seven patients, higher IgE levels were detected in six (85.7%). Most however had normal IgG, IgA and IgM levels. A CD4/CD8 ratio < 1 was detected in three patients (42.9%). Two patients had a score of 5 as they developed autoimmune haemolytic anaemia (AIHA) at the age of 7 years (case 1) and 1 year and a half (case 6). Regular intravenous immunoglobulin (IVIG) with a dose of 400 mg/kg/month was given to all patients. None underwent splenectomy.

Two (cases 2 and 4) received HSCT at the age of 3-mercaptopyruvate sulfurtransferase 1 year and 4 months and 2 years and 5 months, respectively. The stem cell source was bone marrow from unrelated cord blood (case 2) or an HLA-matched sibling (case 4). Both had normal platelet counts within 2 months after HSCT and were alive. Of the patients without HSCT, one died at the age of 4 years due to intracerebral bleeding. Cytomegalovirus infection was found in one patient (case 7) who presented with tachypnea at 2 months of age. He was the first child and born at term to nonconsanguineous parents after an uneventful pregnancy and delivery. His birth weight was 2970 g with head circumference of 30 cm (< 3rd centile). At the age of 2 months, his weight was 3220 g (< 3rd centile) with a length of 52 cm (< 3rd centile) and head circumference of 33 cm (< 3rd centile). He was moderately pale without petechiae.