Natural oscillatory modes of 3D deformation of the human brain in vivo.

Natural modes and frequencies of three-dimensional (3D) deformation of the human brain were identified from in vivo tagged magnetic resonance images (MRI) acquired dynamically during transient mild acceleration of the head. Twenty 3D strain fields, estimated from tagged MRI image volumes in 19 adult subjects, were analyzed using dynamic mode decomposition (DMD). These strain fields represented dynamic, 3D brain deformations during constrained head accelerations, either involving rotation about the vertical axis of the neck or neck extension. DMD results reveal fundamental oscillatory modes of deformation at damped frequencies near 7 Hz (in neck rotation) and 11 Hz (in neck extension). Modes at these frequencies were found consistently among all subjects. These characteristic features of 3D human brain deformation are important for understanding the response of the brain in head impacts and provide valuable quantitative criteria for the evaluation and use of computer models of brain mechanics.

A 3D Computational Head Model Under Dynamic Head Rotation and Head Extension Validated Using Live Human Brain Data, Including the Falx and the Tentorium.

We employ an advanced 3D computational model of the head with high anatomical fidelity, together with measured tissue properties, to assess the consequences of dynamic loading to the head in two distinct modes: head rotation and head extension. We use a subject-specific computational head model, using the material point method, built from T1 magnetic resonance images, and considering the anisotropic properties of the white matter which can predict strains in the brain under large rotational accelerations. The material model now includes the shear anisotropy of the white matter. We validate the model under head rotation and head extension motions using live human data, and advance a prior version of the model to include biofidelic falx and tentorium. We then examine the consequences of incorporating the falx and tentorium in terms of the predictions from the computational head model.

Streptococcus pneumoniae antibody titres in patients with primary antibody deficiency receiving intravenous immunoglobulin (IVIG) compared to subcutaneous immunoglobulin (SCIG).

Intravenous immunoglobulin (IVIG) and subcutaneous immunoglobulin (SCIG) are effective in the treatment of patients with primary antibody deficiency disorders (PAD). The purpose of this study was to evaluate Streptococcus pneumoniae (Spn) antibody titres to 14 serotypes in patients receiving IVIG compared to SCIG and to correlate Spn antibody levels to clinical outcome. The doses of immunoglobulin (Ig)G/kg/month were similar in both IVIG and SCIG groups. In 11 patients treated with IVIG, Spn antibody titres were ≥ 1·3 µg/ml to 99·4 ± 2·1% of the 14 serotypes at peak IVIG but decreased to 66·9 ± 19·8% at trough IVIG. Loss of Spn titres ≥ 1·3 µg/ml was most frequent for Spn serotypes 1, 4, 9V and 23. This correlated with lower Spn antibody titres to these serotypes at peak IVIG compared to the other serotypes. In 13 patients treated with SCIG, Spn antibody titres were protective to 58·2 ± 23·3% of the serotypes 3-5 days after infusion, similar to trough IVIG. Similarly, the Spn serotypes with the least protective percentages were the same as the ones observed in trough IVIG. There were no annualized serious bacterial infections (aSBI) in either group. However, there were significantly decreased annualized other infections (aOI) in the SCIG group compared to the IVIG-treated group, 0·8 ± 0·7 versus 2·2 ± 1·2 infections/patient/year (P = 0·004). Breakthrough aOI did not correlate with protective or higher serum Spn antibody titres.

How do different anterior tibial tendon transfer techniques influence forefoot and hindfoot motion?

BACKGROUND: Idiopathic clubfoot correction is commonly performed using the Ponseti method and is widely reported to provide reliable results. However, a relapsed deformity may occur and often is treated in children older than 2.5 years with repeat casting, followed by an anterior tibial tendon transfer. Several techniques have been described, including a whole tendon transfer using a two-incision technique or a three-incision technique, and a split transfer, but little is known regarding the biomechanical effects of these transfers on forefoot and hindfoot motion. QUESTIONS/PURPOSE: We used a cadaveric foot model to test the effects of three tibialis anterior tendon transfer techniques on forefoot positioning and production of hindfoot valgus. METHODS: Ten fresh-frozen cadaveric lower legs were used. We applied 150 N tension to the anterior tibial tendon, causing the ankle to dorsiflex. Three-dimensional motions of the first metatarsal, calcaneus, and talus relative to the tibia were measured in intact specimens, and then repeated after each of the three surgical techniques. RESULTS: Under maximum dorsiflexion, the intact specimens showed 6° (95% CI, 2.2°-9.4°) forefoot supination and less than 3° (95% CI, 0.4°-5.3°) hindfoot valgus motion. All three transfers provided increased forefoot pronation and hindfoot valgus motion compared with intact specimens: the three-incision whole transfer provided 38° (95% CI, 33°-43°; p < 0.01) forefoot pronation and 10° (95% CI, 8.5°-12°; p < 0.01) hindfoot valgus; the split transfer, 28° (95% CI, 24°-32°; p < 0.01) pronation, 9° (95% CI, 7.5°-11°; p < 0.01) valgus; and the two-incision transfer, 25° (95% CI, 20°-31°; p < 0.01) pronation, 6° (95% CI, 4.2°-7.8°; p < 0.01) valgus. CONCLUSION: All three techniques may be useful and deliver varying degrees of increased forefoot pronation, with the three-incision whole transfer providing the most forefoot pronation. Changes in hindfoot motion were small. CLINICAL RELEVANCE: Our study results show that the amount of forefoot pronation varied for different transfer methods. Supple dynamic forefoot supination may be treated with a whole transfer using a two-incision technique to avoid overcorrection, while a three-incision technique or a split transfer may be useful for more resistant feet. Confirmation of these findings awaits further clinical trials.

[Briard's sagittal sliding osteotomy of the lateral condyle in total knee arthoplasty of the severe valgus knee]. / Die sagittale Gleitosteotomie des lateralen Kondylus nach Briard beim Oberflächenersatz des kontrakten Valgusknies.

OBJECTIVE: Distalization of the insertion of the lateral collateral ligament and popliteus tendon by sliding osteotomy of the lateral femur condyle in order to correct a residual contracture in extension in total knee arthroplasty (TKA) of the severe valgus deformity. INDICATIONS: Genuine and other valgus deformity of the knee. CONTRAINDICATIONS: Severe laxity of the medial collateral ligament; common contraindications of joint replacement. SURGICAL TECHNIQUE: Lateral parapatellar approach and stepwise osteotomy of the tubercle of the tibia, subperiostal release of the lateral contracted structures such as iliotibial band (ITB) and lateral collateral ligament (LCL) in flexion. Tibia first technique, verification of a balanced and stable flexion gap parallel to the epicondylar line. Posterior cruciate ligament (PCL) is preserved. Referencing of the distal femoral cut by a spacer filled only in the medial extension gap. Finishing femoral chamfer cuts. If extension gap remains trapezoidal, further release of the residual lateral contracted structures in extension by means of sliding osteotomy of the lateral condyle and subperiostal release of the capsule and the lateral septum intermusculare is required. Termporary fixation of the lateral condyle by K-wires, resection of the bony excess, trial of test components, definite screw fixation. POSTOPERATIVE MANAGEMENT: Comparable to TKA in varus deformities by a medioparapatellar approach. RESULTS: A total of 79 patients (61 women, 18 men, average age 71 years at the time of surgery) with fixed valgus deformities were operated between June 2001 and December 2010 using TKA and sliding osteotomy of the lateral femoral condyle. The preoperative valgus angle under defined valgus and varus stress was 19.5° (8-40), postoperative 4.7° (2-11). Mean medial angle (valgus stress) of the follow-up was 2.1° (0.5-5°), lateral angle (varus stress) 2.3° (0.5-5°). A total of 35 patients were followed-up, at a mean of 73.3 month (24-109 months). The postoperative Knee Society Score was 95 points (56-100 points), while the postoperative Function Score was 90 points (55-100 points) postoperatively. The Oxford Score improved from 22 points (3-43 points) preoperatively to 45 points (21-48 points) postoperatively. One knee had to be revised due to infection, one knee due to non-union of the tibial tubercle. Finally, there were 3 cases with complications associated with the procedure due to the sliding osteotomy of the lateral femoral condyle; all were revised successfully. No conversion to a semi-constrained or constrained knee prosthesis was necessary.

Mold-sensitivity in children with moderate-severe asthma is associated with HLA-DR and HLA-DQ.

BACKGROUND: Several epidemiologic studies in the United States and Europe have linked Alternaria sensitivity to both persistence and severity of asthma. In this study, we examined T cell responses and HLA class II alleles in children with moderate-severe asthma. METHODS: Ninety-six children with moderate-severe asthma were compared to 90 children with mild asthma. HLA class II genotyping was performed to determine HLA allelic frequencies. Th1/Th2 Alternaria-specific T cell cytokine responses were determined by the use of Alternaria-stimulated cultures. HLA class II restriction was examined by inhibition of Alternaria-stimulated lymphoproliferative responses with blocking anti-HLA class II monoclonal antibodies. RESULTS: Children with moderate-severe asthma had significantly increased sensitivities to Aspergillus fumigatus; sensitivities to Alternaria were similar in both moderate-severe and mild asthmatics. The frequency of HLA-DRB1*13 alleles were increased in mold-sensitive moderate-severe asthmatic children. HLA-DRB1*03 tended to be increased in mold-sensitive moderate-severe asthmatics. The frequency of HLA-DQB1*03 alleles was significantly decreased in mold and Alternaria-sensitive moderate-severe asthma. HLA class II blocking monoclonal antibodies demonstrated HLA-DR restriction. Alternaria-stimulated IL-5 and IL-13 synthesis was significantly increased in moderate-severe asthmatics. IL-5 and IL-13 synthesis was significantly increased in Alternaria-stimulated lymphocyte cultures of HLA-DQB1*03- asthmatics compared to HLA-DQB1*03+ asthmatics. CONCLUSIONS: In children with Alternaria-sensitive moderate-severe asthma, there was increased Th2 sensitivity to Alternaria stimulation. This was associated with HLA-DR restriction and with increased frequency of HLA-DRB1*13 and HLA-DRB1*03. There was decreased frequency of HLA-DQB1*03 in Alternaria-sensitive moderate-severe asthma, suggesting HLA-DQB1*03 may be protective of the development of Alternaria-sensitive severe asthma.

Clinical and biological significance of angiogenesis and lymphangiogenesis in colorectal cancer.

BACKGROUND: Angiogenesis and lymphangiogenesis are essential for tumour development and progression. However, in colorectal cancer (CRC), the relationship between angiogenesis and clinical outcome is controversial, and the prognostic significance of lymphangiogenesis is not well examined because of the lack of specific a marker for lymphatic vessels. AIMS: To evaluate blood microvessel density (MVD) following the proposed standard method for MVD assessment given by the first international consensus and lymphatic vessel density (LVD), and investigate their clinicopathologic and biologic significance in CRC. METHODS: MVD and LVD in primary tumours (n=210), along with their corresponding adjacent normal mucosa (n=105) and distant normal mucosa (n=27) specimens, were immunohistochemically examined by using CD31 and D2-40 antibodies. RESULTS: Both MVD and LVD were higher in tumour compared with the corresponding normal mucosa. In tumours, MVD was positively related to particular interesting new cysteine-histidine-rich protein (PINCH) expression (P=0.006), but not with clinicopathologic variables. LVD, in both intratumoural and peritumoural areas of tumours, was reversely related to Dukes' stage. There was no association between MVD or LVD and patients' survival (P>0.05). CONCLUSIONS: Angiogenesis and lymphangiogenesis occurred in CRC development, but were not related to CRC patient prognosis. PINCH may play a potential role in tumour angiogenesis.

Successful umbilical cord blood stem cell transplantation in a patient with Rothmund-Thomson syndrome and combined immunodeficiency.

The ATP-dependent DNA helicase Q4 (RECQL4) belongs to a family of conserved RECQ helicases that are felt to be important in maintaining chromosomal integrity (Kitao et al., 1998, Genomics: 54 (3): 443-452). Deletions in the RECQL4 gene located on chromosome 8 region q24.3 have been associated with Rothmund-Thomson syndrome (RTS, OMIM 268400), a condition characterized by poikiloderma, sparse hair, small stature, skeletal abnormalities, cataracts and an increased risk of malignancy. We present a patient with a molecularly confirmed diagnosis of RTS with two unique genetic alterations in RECQL4 (IVS16-2A>T and IVS2+27_51del25), who at the age of 7 months nearly succumbed to Pneumocystis carinii pneumonia. Evaluation of his immune system demonstrated a T- B+ NK- phenotype with agammaglobulinemia consistent with combined immunodeficiency (CID). Studies to evaluate for known genetic causes of CID were not revealing. The patient received an umbilical cord blood (UCB) transplant with complete immune reconstitution. This report represents the first description of a CID phenotype and UCB transplantation in a patient with RTS.

Phylogenetic analyses of the Fusarium poae, Fusarium sporotrichioides and Fusarium langsethiae species complex based on partial sequences of the translation elongation factor-1 alpha gene.

Phylogenetic relationships between four Fusarium species were studied using parts of the nuclear translation elongation factor-1 alpha (EF-1alpha) gene as a phylogenetic marker. Sequences from 12 isolates of Fusarium poae, 10 isolates of Fusarium sporotrichioides and 12 isolates of Fusarium langsethiae yielded 4, 5 and 5 haplotypes, respectively. In addition, we included one isolate of Fusarium kyushuense. The aligned sequences were subjected to neighbor-joining (NJ), maximum parsimony and maximum likelihood (ML) analyses. The results from the different analyses were highly concordant. The EF-1alpha-based phylogenies support the classification of F. langsethiae as a separate taxon in the section Sporotrichiella of Fusarium, as the closest sister taxon to F. sporotrichioides, while F. kyushuense is the sister taxon to F. poae. This corresponds well with the ability of F. langsethiae and F. sporotrichioides to produce T-2 and HT-2 toxins. In contrast, morphological characters indicate a closer relationship between F. langsethiae and F. poae on the one hand, and between F. sporotrichioides and F. kyushuense on the other hand.

IgE antibody to Aspergillus fumigatus recombinant allergens in cystic fibrosis patients with allergic bronchopulmonary aspergillosis.

BACKGROUND: Allergic bronchopulmonary aspergillosis (ABPA) in cystic fibrosis (CF) is characterized by a heightened Th2 CD4+ T-cell response to Aspergillus fumigatus (Af) allergens and a hyper-immunoglobulin E (IgE) state compared with cystic fibrosis patients without ABPA. The IgE serologic differentiation of ABPA from atopic CF patients can be difficult. We propose as the reactivity with purified antigens varies qualitatively and quantitatively and that the antibody response is more specific than with crude Af antigen extract, the IgE responses to purified recombinant Af allergens may differentiate ABPA from atopic CF patients. METHODS: Serum IgE reactivity to seven recombinant purified allergens and to a crude extract of Af was measured in 15 ABPA, in 23 Af skin test positive (ST+), and in 19 Af skin test negative (ST-) CF patients. Four of the ABPA CF patients were studied before and after developing ABPA. Nine ABPA patients were studied during flares and remissions of ABPA. RESULTS: Allergic bronchopulmonary aspergillosis patients had significantly increased IgE reactivity to Asp f2, f3, f4, f6, and f16 compared with the Af ST+ and ST- non-ABPA CF patients. In the ABPA patients studied before and after developing ABPA, IgE reactivity also increased to Asp f2, f3, f4, and f6, and to the crude extract. In ABPA CF patients, IgE reactivity to Asp f1, f2, f3, and f6 significantly increased during periods of ABPA flares compared with periods of remission. Analysis of the receiver operating curve demonstrated that IgE reactivity to Asp f3 and f4 gave the best sensitivity and specificity and were better than IgE reactivity to a crude extract of Aspergillus. Furthermore, in ABPA patients studied during periods of remission the IgE reactivity to Asp f3 and f4 remained significantly elevated compared with Af ST+ non-ABPA patients. The IgE responses when considered either to be positive or negative to Asp f3 and f4 significantly differentiated ABPA from Af ST+ and ST- non-ABPA CF patients. In contrast, IgE reactivity was considered positive to the crude extract in 89% of ABPA, 61% of Af ST+, and 0% of Af ST- non-ABPA CF patients. CONCLUSIONS: Immunoglobulin E reactivity to a panel of purified Af allergens, especially to Asp f3 and f4, differentiates ABPA from atopic Af ST+ non-ABPA CF patients. Serial determinations of IgE reactivity to individual purified Aspergillus antigens, especially Asp f3, demonstrates that increases in IgE reactivity may provide improved distinction between stages of flares and remission compared with changes in IgE reactivity to a crude Aspergillus extract.

Increased sensitivity to IL-4 in cystic fibrosis patients with allergic bronchopulmonary aspergillosis.

BACKGROUND: Allergic bronchopulmonary aspergillosis (ABPA) is characterized by a heightened Th2 CD4+ T-cell response to Aspergillus fumigatus allergens and a hyper-immunoglobulin (Ig)E state compared with cystic fibrosis patients without ABPA. We hypothesize that one reason for this response is increased sensitivity to interleukin (IL)-4 in ABPA resulting in increased expression of CD23 and CD86 and leading to a positive amplification mechanism that increases Th2 CD4+ T cell responses. METHODS: Peripheral blood mononuclear cells (PBMC) were isolated from seven ABPA CF and 19 non-ABPA CF patients and 16 nonatopic controls and stimulated with rIL-4 (range 0.1-10 ng/ml) and rIL-13 (range 1-10 ng/ml) for 48 h. The number of CD23 molecules and percentages of CD23+ B cells were quantified by flow cytometry. Both phorbol 12-myristate 13-acetate (PMA)/ionomycin (IO) and antigen stimulated, toxoid and Asp f2/f3/f4, PBMC were examined for cytoplasmic cytokine synthesis enumerated by cytokine staining using flow cytometry to measure Th2 and Th1 CD3+ T cells. RESULTS: The numbers of CD23 molecules on B-cells were significantly elevated at time 0 in ABPA CF patients compared with both non-ABPA CF patients and nonatopic controls. Following IL-4 stimulation in vitro, the numbers and percentages of CD23 expression on B cells were significantly up-regulated in ABPA CF patients compared with non-ABPA CF patients and controls. The IL-13 stimulation up-regulated CD23 expression; however, there was no significant difference in ABPA CF patients compared with non-ABPA CF patients and controls. The percentages of interferon (IFN)-gamma+ CD3+T cells following PMA/IO stimulation were significantly decreased in both ABPA and non-ABPA CF patients compared with controls. There were no significant differences of IL-4+ and IL-13+ CD3+ T cells between ABPA and non-ABPA CF patients. When tetanus toxoid stimulated T cells were examined, both ABPA and non-ABPA CF patients had significantly decreased IFN-gamma+ CD3+ T cells compared with controls. In Asp f2/f3/f4 stimulated T cells, ABPA CF patients had significantly increased IL-4+ CD3+ T cells compared with non-ABPA CF patients and controls. CONCLUSIONS: ABPA CF patients have increased sensitivity to IL-4 but not to IL-13 up-regulation of CD23 molecules compared with non-ABPA CF patients. There were decreased percentages of IFN-gamma+ and IL-2+ Th1 T cells in CF patients compared with nonatopic controls but similar percentages of IL-4+ Th2 T cells in all three groups. However, ABPA CF patients had increased frequency of Aspergillus-stimulated Th2 T cells. This indicated that there is skewing of Th2 T cells in ABPA CF patients. Thus, in CF ABPA patients there is increased Th2 T cells and increased sensitivity to IL-4.

Umbilical cord blood transplantation in severe T-cell immunodeficiency disorders: two-year experience.

Hematopoietic stem cell transplantation is the treatment of choice for severe primary T-cell immunodeficiencies. When an HLA-identical sibling as the donor is not available, an alternative donor stem cell source is needed. In primary T-cell immunodeficiencies, T-cell-depleted HLA-haploidentical bone marrow transplantation has been particularly successful in reconstituting the immune system in many but not all of the severe T-cell immune deficiency disorders. This study reports the use of umbilical cord blood (UCB) stem cell transplantation in severe T-cell immune deficiency. Umbilical cord blood was evaluated as a stem cell source for immune reconstitution in children with severe primary T-cell immunodeficiency disorders, such as severe combined immunodeficiency syndrome (SCID), reticular dysgenesis, thymic dysplasia, combined immunodeficiency disease (CID), and Wiskott-Aldrich syndrome (WAS) when a matched sibling donor was unavailable. From 1/96 through 5/98, eight children received unrelated cord blood stem cell transplantation following a preparative regimen for the treatment of combined immunodeficiency diseases. The patients ranged in age from 2 weeks to 8 years. The cord blood units were 3/6 HLA antigen matches in two children. 4/6 in four children, and 5/6 in two child, with molecular HLA-DR mismatch in three of the children. The average time for neutrophil engraftment (absolute neutrophil count >500/mm3) was 12 days (range 10-15 days) and the average time for platelet engraftment (platelet count >20,000/mm3) was 36 days (range 24-50 days). A patient with reticular dysgenesis failed to engraft following her first transplant, but fully engrafted after a second unrelated donor cord blood transplantation. Five of six patients exhibited grade I graft-versus-host disease (GvHD). while one child had grade IV skin and gut GvHD. Immunologic reconstitution demonstrated that cord blood stem cell transplantation resulted in consistent and stable T-, B- and natural killer (NK) cell development. The kinetics of development were such that T-cell development occurred between 60 to 100 days. Initial T-cell engraftment consisted predominantly of CD45RO+, CD3+, and CD4+ T cells, and at 12 to 24 months changed to CD45RA+, CD3+, and CD4+ T cells, indicating de novo maturation of T cells. NK cell development occurred at approximately 180 days. B cells engrafted early, and study of functional B-cell antibody responses revealed that five of six patients in whom intravenous immune globulin has been discontinued have low detectable antibody responses to tetanus and diphtheria toxoid immunizations at 18 to 24 months posttransplantation. Unrelated umbilical donor cord blood is an alternative source of stem cells for transplantation in children with severe T-cell immune deficiency disorders when a suitable HLA-matched donor is not available and when a T-depleted haploidentical preparation is not beneficial. Benefits of UCB include rapid and reliable recovery of immune function, low risk of GvHD, and low viral transmission rate.

Increased sensitivity to IL-4 in patients with allergic bronchopulmonary aspergillosis.

BACKGROUND: Allergic bronchopulmonary aspergillosis (ABPA) is characterized by a heightened Th2 CD4+ cell response to Aspergillus fumigatus allergens and a hyper-IgE state compared to atopic asthmatic and cystic fibrosis patients without ABPA. We hypothesized that one reason for this response is increased sensitivity to IL-4 in ABPA, resulting in increased expression of CD23 and CD86, leading to a positive amplification mechanism which increases Th2 CD4+ T cell responses. METHODS: Peripheral blood mononuclear cells isolated from 10 ABPA, 9 atopic, and 8 nonatopic subjects and stimulated for 48 h with varying concentrations of rIL-4 ranging from 0.1 to 50 ng/ml. The percentages of CD23+ and CD86+ B cells and the number of CD23+ molecules on CD20+ and CD86+CD20+ B cells were quantified by flow cytometry. RESULTS: Total serum IgE levels were elevated in ABPA patients compared to atopic and nonatopic controls. At day 0 prior to culture, CD23 molecules per CD20+ B cell were significantly elevated in ABPA patients compared to atopic and to nonatopic patients. CD23 molecules per CD20+ B cell in ABPA and atopic patients decreased after 48 h in culture without IL-4 added and were similar. With IL-4 stimulation, ABPA patients had significantly increased rates of CD23 expression per B cell compared to atopic and nonatopic subjects (p < 0.001). Furthermore, ABPA had significantly increased numbers of CD23+ molecules per B cell and CD86+ B cell following IL-4 stimulation compared to atopic and nonatopic patients. Both ABPA and atopic patients at day 0 prior to culture had increased expression of CD86+ and CD23+CD86+ B cells compared to nonatopic patients. After 48 h in culture without IL-4, the percentages of CD86+ and CD23+CD86+ B cells decreased in ABPA and atopic patients. After stimulation with IL-4, ABPA patients had significant upregulation of CD23+CD86+ B cells compared to atopic and nonatopic patients. Similarly, the number of CD23 molecules per CD86+CD20+ B cell was significantly upregulated following IL-4 stimulation in ABPA patients compared to atopic and to nonatopic subjects. CONCLUSIONS: This is the first study to demonstrate that ABPA patients have increased sensitivity to IL-4 stimulation compared to other atopic individuals, such that ABPA > atopic >> nonatopic patients. The B cells from ABPA patients were significantly more sensitive to IL-4 stimulation compared to atopic and nonatopic patients with upregulation of CD23 and CD86 expression. ABPA subjects had increased CD86+ and CD23+CD86+ B cell expression on day 0 prior to culture and with upregulation of CD23+ molecules on CD86+CD20+ B cells. IL-4 also stimulated upregulated CD86+ expression on B cells in atopic patients with little effect on nonatopic patients. This study supports the premise that IL-4, IL-4R alpha and CD86 are central targets in the treatment of ABPA and atopic disease.

Inhibition of thymopoiesis of CD34+ cell maturation by HIV-1 in an in vitro CD34+ cell and thymic epithelial organ culture model.

The mechanisms by which HIV-1 affects thymopoiesis were determined by preincubating CD34+ cells or cultured thymic epithelial (CTE) cells with lymphotropic (T-) and monotropic (M-) strains of HIV-1 in an in vitro CTE organ and CD34+ cell coculture model that allows for analysis of development of thymocytes and mature T cells. When purified CD34+ cells were precultured with either T- or M-tropic strains of HIV-1, thymopoiesis was impaired in a two-week coculture manifested by decreased cell number of thymocytes generated. However, the percentages of thymocyte subpopulations were comparable to control uninfected cocultures. Furthermore, HIV infection of thymocytes was predominantly observed in the CD44+CD3- population. However, in a four-week coculture experiment, HIV infection and depletion of more mature thymocytes were also observed. When CTE cells were preincubated with T- and M-tropic strains of HIV before addition of CD34+ cells, the number of thymocytes and subpopulations of thymocytes at early and later stages of maturation were markedly decreased. Furthermore, CD34+ and CD44+CD3- cells become HIV-infected. In summary, HIV-1 infection inhibited thymocyte maturation at early stages of thymocyte maturation CD44+CD25-CD3-. In addition, HIV also depleted later stages of CD4+ thymocyte subpopulations.

B-lymphocyte aggregates in alveoli from a child with hypersensitivity pneumonitis (bird breeders lung).

BACKGROUND: Hypersensitivity pneumonitis is an interstitial lung disease mediated through a patient's immunologic response to a variety of inhaled organic dusts. Studies of the cellular components of lavage fluid from patients with this disease show marked increases of CD8+ suppressor/cytotoxic T-lymphocytes. OBJECTIVE: In this study, we identified, in addition to the expected suppressor T-cells and natural killer cells, follicle-like aggregates of B-cells in the lung interstitium of an affected patient. METHODS: The patient was an 11-year-old non-asthmatic, Caucasian male who presented with a 4-month history of progressive dyspnea, cough, and fever. The home contained nine cockatiel and two doves. Admission pulmonary functions revealed a restrictive pattern with diminished diffusion capacity. Prior to a diagnosis, the patient underwent bronchoalveolar lavage and transbronchial biopsy. Serum precipitins were eventually positive to pigeon (which cross-reacts with dove) droppings. The symptoms resolved after a prolonged course of prednisone. RESULTS: Analysis of bronchoalveolar lavage lymphocyte population revealed a predominance of CD8+ cells (50%) with 85% expressing the activation marker HLA-DR. The percentage of CD4+ and CD56+ were 32% and 16%, respectively. The transbronchial biopsy revealed CD20+ follicle-like aggregates within the lung interstitium. CONCLUSIONS: The histopathologic findings confirm that in hypersensitivity pneumonitis, the predominant immune response is an infiltrate of CD8+ T cells. The presence of B cell aggregates, however, may indicate that the local synthesis of antibody may be involved in an antibody-dependent cellular cytotoxic mechanism.

Thymosin-alpha1 stimulates maturation of CD34+ stem cells into CD3+4+ cells in an in vitro thymic epithelia organ coculture model.

The effect of thymosin-alpha1 on thymopoiesis is largely unknown. Thymosin is found in the cortical and medullary thymic epithelia, as well as in nurse cells; thus, it is hypothesized that thymosin may affect both early and late stage of thymocyte maturation. In this study, the effect of thymosin-alpha1 on thymopoiesis was determined by coculturing in vitro CD34+ stem cells (SC) with allogeneic cultured thymic epithelia fragments (CTEF) for 1-4 weeks and analyzing T-cell maturation by flow cytometry. Thymosin-alpha1 significantly enhanced the cell number (e.g., proliferation) of mononuclear cells obtained at 2 and 4 weeks of the SC-CTEF cocultures (P < 0.01 and < 0.05, respectively). In particular, thymosin-alpha1 stimulated expression of CD3+ cells at 3 and 4 weeks (P < 0.05). The predominant subpopulation increased by thymosin stimulation was single positive mature CD4+ cells, which was confirmed to occur within the SC-CTEF thymic organ tissue by laser confocal immunofluorescence microscopy. Thymosin stimulation tended to enhance IL-7 synthesis, critical cytokine in the maturation of thymocytes. In summary, this is the first study to demonstrate that thymosin-alpha1 enhanced thymopoiesis of CD34+ stem cells in humans using an in vitro model of differentiation using stem cells and cultured thymic epithelial fragments cocultures. Furthermore, the thymosin significantly increased expression of CD3+4+ T cells.

Kinetics of T-cell development of umbilical cord blood transplantation in severe T-cell immunodeficiency disorders.

BACKGROUND: Hematopoietic stem-cell transplantation is the treatment of choice for severe primary T-cell immunodeficiencies. When an HLA-identical sibling donor is not available, an alternative donor stem-cell source is needed. In primary T-cell immunodeficiencies, T-cell-depleted HLA-haploidentical bone marrow transplantation has been particularly successful in reconstituting the T-cell immune system in many of the severe combined immunodeficiency syndrome types. However, there are some problems associated with this preparation as a stem donor source, such as increased resistance to engraftment, a long period of time for T-cell engraftment to occur, and failure to engraft B cells and B-cell functions. These problems can be especially troublesome if the patient is infected before the transplantation. OBJECTIVE: Umbilical cord blood was evaluated as a stem-cell source for immune reconstitution in children with severe primary T-cell immunodeficiency disorders, such as severe combined immunodeficiency syndrome, reticular dysgenesis, thymic dysplasia, and combined immunodeficiency disease, when a matched sibling donor was unavailable. METHODS: From January 1996 through July 1997, 6 children received unrelated cord blood stem-cell transplantation after a preparative regimen for the treatment of combined immunodeficiency diseases. The patients ranged in age from 2 weeks to 6 years. The cord blood units were 3 of 6 HLA antigen matches in 2 children, 4 of 6 HLA antigen matches in 3 children, and 5 of 6 HLA antigen matches in 1 child, with molecular HLA-DR mismatch in 3 of the children. RESULTS: The average time for neutrophil engraftment (absolute neutrophil count, >500/mm3) was 12 days (range, 10 to 15 days), and the average time for platelet engraftment (platelet count, >20,000/mm3) was 36 days (range, 24 to 50 days). In a patient with reticular dysgenesis, the first transplant failed to engraft but fully engrafted after a second unrelated donor cord blood transplantation. Five of 6 patients exhibited grade I graft-versus-host disease (GvHD), although 1 child experienced grade IV skin and gut GvHD. Immunologic reconstitution demonstrated that cord blood stem-cell transplantation resulted in consistent and stable T-cell, B-cell, and natural killer-cell development. The kinetics of recovery of phenotypic expression and function of T cells occurred between 60 to 100 days and that of natural killer cells at approximately 180 days. B cells engrafted early, and a study of functional B-cell antibody responses revealed that 2 of 2 patients in whom intravenous immune globulin was discontinued have low detectable antibody responses to tetanus and diphtheria toxoid immunizations more than 1 year after the transplantation. CONCLUSIONS: Unrelated umbilical donor cord blood is an excellent source of stem cells for transplantation of children with immune deficiency disorders. Benefits include rapid and reliable recovery of immune function, low risk of GvHD, and low viral transmission rate.

Selective antibody deficiency to bacterial polysaccharide antigens in patients with Netherton syndrome.

Three patients with Netherton syndrome, recurrent sinopulmonary infections, and humoral immune deficiency are described. Although quantitative serum immunoglobulin levels were generally normal, two patients had selective antibody deficiency to bacterial polysaccharide antigens, one associated with IgA-IgG-2 deficiency. A third patient had an antibody deficiency to protein antigens. This is the first report, to our knowledge, that describes antibody deficiency in patients with Netherton syndrome. This finding demonstrates the importance of evaluating functional antibody responses to both protein and bacterial polysaccharide antigens and not relying on IgG subclass determination.