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Introduction: Penicillin allergy is suspected in 10% of hospital inpatients but can be disproved in 90% of cases. Direct oral provocation without preceding tests among low-risk patients has proven to be safe in studies of both children and adults and is gaining use across the world. The aims of this study were to investigate the rate of severe allergic reactions to direct oral drug provocation, without preceding tests, in penicillin allergy patients stratified to be at low risk, as well as to examine if these patients have barriers to penicillin allergy de-labeling and future use of penicillins. Methods: Adult patients referred to a university hospital allergy clinic with a suspected penicillin allergy were prospectively risk evaluated. Patients stratified to be at low risk were offered a direct oral provocation with a single-dose amoxicillin followed by 4 days of continued treatment. The same risk stratification criteria were applied to a larger retrospective cohort. Results: In the prospective study population, 202 patients had a direct oral drug provocation and 20 (10%) were positive. There were no cases of anaphylaxis or severe delayed hypersensitivity. Fifteen reactions were benign rashes with onset >1 day after initial dosing, and 13 of these were maculopapular rashes. The same low-risk criteria were applied retrospectively to patients in a drug provocation database, and 1,759 patients fulfilled the criteria; of these, 10% had positive provocations, and there were no cases of anaphylaxis or severe delayed hypersensitivity. De-labeled patients in the prospective study reported not to fear future penicillin intake, after prolonged provocation. Conclusion: The risk stratification criteria for identifying low-risk patients for the oral drug provocation test without prior skin testing were safe in terms of avoiding anaphylaxis or severe delayed hypersensitivity. Benign delayed skin reactions still occurred, and access to allergy advice and follow-up is necessary. [ABSTRACT FROM AUTHOR]

Background: Intradermal testing with delayed reading (IDTdr), used routinely in many centers, may identify delayed reactions to penicillins. However, few studies have compared the results of IDTdr with drug provocation test (DPT). The aim of this study was to examine the proportion of provocation-positive patients testing positive on IDTdr. Methods: Fifty-seven patients with a positive DPT occurring >2 h after intake of penicillin V, dicloxacillin, pivampicillin, or amoxicillin had an IDTdr with penicillin G, amoxicillin, ampicillin, and dicloxacillin. A control group included 18 patients with negative DPTs with the suspected penicillin. Results: In total 25% (n = 14) of provocation-positive patients tested positive on IDTdr. Among patients with positive IDTdr, 9/14 (64%) versus 11/43 (26%) in the IDTdr negative group (p < 0.05) had required oral steroids to treat skin reactions following DPT. No other differences between IDTdr positive and negative groups were found. No controls had a positive IDTdr. Conclusion: Investigating with IDTdr would have identified 25% of patients with a DPT-verified allergy with delayed reactions. It is difficult to target subgroups who will test positive on IDTdr. There were more patients who tested positive on IDT who had received oral steroids after DPT, and this may be an indication that skin reaction severity plays a role in skin testing diagnostics. Further potential predictors for positivity of IDTdr, such as duration of skin symptoms, should be assessed in large studies in order to optimize the investigations of nonimmediate drug allergic reactions. [ABSTRACT FROM AUTHOR]

Tattoos have become increasingly popular worldwide making adverse effects from tattoos a growing concern. In our report, we present a 51-year-old man who developed an unusual allergic reaction to the red ink portions of his tattoos that coincided with the initiation of ledipasvir/sofosbuvir treatment for his hepatitis C. Clinical and histological features were consistent with a delayed-type hypersensitivity reaction to red ink. [ABSTRACT FROM AUTHOR]

Background: Food protein-induced enterocolitis syndrome (FPIES) is a non-IgE-mediated food allergy. The pathological mechanism of FPIES is intestinal inflammation, and cell-mediated hypersensitivity is presumed to play an important role in its development. Case Report: The first case in which significant fetal intestinal distension suggested fetal onset of FPIES is reported. A 2,334-g male was born at 34 weeks by vaginal delivery. Results: In utero, he had significant intestinal distension on ultrasonography and MRI. A few hours after the first feeding, he produced bloody stool and showed abdominal distension. In this case, FPIES was not only caused by cow's milk protein diagnosed clinically and by an allergen-specific lymphocyte stimulation test, but also by breast milk diagnosed by oral food challenge. The clinical course and laboratory results strongly suggested not only fetal sensitization but also fetal onset. Conclusion: This report might be helpful for prompt diagnosis and treatment and, furthermore, lead to elucidation of the pathogenesis and pathophysiology of FPIES. [ABSTRACT FROM AUTHOR]

Background: The double-blind, placebo-controlled food challenge (DBPCFC) is still considered to be the gold standard in food allergy diagnosis. This test is however not common practice in routine due to several practical limitations, especially for non-IgE-mediated food allergy with its typical delayed food allergic reactions. Objective: The aim of this study was to develop and evaluate DBPCFC matrices for the diagnosis of milk and egg allergies which can be applied at home for the diagnosis of delayed food allergic reactions. The main focus was the blinding of milk and raw egg and the development of matrices which can be prepared and consumed conveniently at home with a sufficiently long shelf life (+/– 6 months or longer). Methods: A sensory test evaluated the blinding of the egg and milk in the matrices. The microbiological analysis confirmed the safety and stability of the developed matrices. To assess the applicability of the matrices, a pilot DBPCFC study for milk including 7 patients was conducted. Results: Sensory tests confirmed that the masking of the allergenic ingredients was sufficient. Microbial safety and stability of the matrices were confirmed up to 6 months of storage at ambient temperatures in the dark. The DBPCFC for milk showed different outcomes and proved its applicability for use at home. Conclusion: A novel stable DBPCFC matrix for milk and raw egg has been developed that allows convenient use at the patients' home. [ABSTRACT FROM AUTHOR]

Background: Allergic contact dermatitis (ACD) is an inflammatory skin disease caused by repeated skin exposure to contact allergens. The severity and duration of this disease are associated with many different factors. Some of these factors may represent markers for monitoring disease activity and the individual response to an intervention. Methods: We used a targeted metabolomics approach to find such factors in the serum of individuals with ACD. Metabolomics profiles were examined and compared in the acute phase of the disease and also in the absence of disease activity. Results: Our study identified a significant remission phase of ACDassociated systemic biochemical shifts in 2 metabolic pathways: tryptophan-kynurenine and phenylalanine-tyrosine. Conclusions: Although the responsible mechanisms are unclear, these results suggest that the remission phase of ACD is linked to tryptophan metabolism via kynurenine and phenylalanine- tyrosine pathways. However, further replication studies with a larger number of subjects and their subgroups are necessary to validate our results. These studies may provide a new perspective with which to understand the mechanism of and find potential biomarkers of ACD, as well as a new reference for personalized treatment. [ABSTRACT FROM AUTHOR]

We present tocilizumab desensitization of a 47-year-old woman affected by rheumatoid arthritis with full body delayed erythematous urticarial reaction. Skin test for tocilizumab gave cutaneous reaction after 6 h at 20 mg/mL. The schedule of desensitization was then adapted for non-immediate reaction. We prepared a desensitization procedure reaching the cumulative dose of 516 mg in 5 weeks. After 6 months, the repetition of skin tests had a negative result, with demonstration of tolerance induction. Today the patient has good control of the disease. [ABSTRACT FROM AUTHOR]

Background: Egg allergy is one of the most common food allergies in children. The standard therapy for egg allergy is strict avoidance. Yet, there is considerable clinical and scientific interest in primary or secondary prevention. A major drawback of oral tolerance (OT) induction protocols, however, is the possibility of severe side effects; thus, we have formulated a hypoallergenic egg product and demonstrate its in vivo capacity to modulate the immune system in the current study. Methods: Hydrolyzed egg (HE) was produced using a combination of moderate heat treatment and enzymatic hydrolysis. The capacity of HE to induce OT was tested in experimental models and compared to whole egg (WE). Delayed-type hypersensitivity (DTH) responses, immune markers and potential early markers of OT were analyzed. Results: Allergic responses, assessed by both DTH responses upon OVA challenge and serum OVA-specific IgE and IgG1, were decreased after treatment with HE and WE compared to the control group. Additionally, feeding WE and HE significantly decreased Th2 cytokine induction and cell proliferation, induced the activation of effector CD4+ T cells and increased numbers and percentages of ICOS+CD4+CD25+Foxp3+ cells. Furthermore, DO11.10 mouse experiments showed that HE contains other peptides than the OVA323-339 peptide that are able to induce tolerance to OVA. Conclusions: Altogether, results showed that HE induces OT in mice in a dose-dependent manner. Due to its low allergenicity compared to WE, it may represent a safer alternative for OT induction in at-risk subjects or oral immunotherapy in allergic patients. © 2014 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: Patients with allergic bronchial asthma can develop various types of asthmatic response to bronchial challenge with allergens, such as immediate (IAR), late (LAR) or delayed (DYAR) response, due to different immunological mechanisms. Objective: The DYAR, beginning within 26- 32 h after the challenge, reaching its maximum between 32 and 48 h and resolving within 56 h (p < 0.001), differs from IAR and LAR regarding the clinical features, diagnostic and immunological parameters. Methods: The repeated DYAR (p < 0.001) in 28 patients was supplemented with recording of cytokine concentrations in the serum before and up to 72 h after the bronchial challenge by means of enzyme-linked immunoassay. Results: The DYAR was accompanied by a significant increase in the serum concentration (p < 0.05) of IL-2 at 24, 36 and 48 h; IL-10 at 12, 24, 36 and 48 h; IL-18 at 12 and 24 h; IFN-γ at 24, 36, 48 and 56 h; G-CSF at 1 and 12 h; TNF-α at 12, 36 and 48 h and TGF-β at 12 and 36 h, and a significant decrease in the concentration (p < 0.05) of IL-7 at 36 and 48 h and IL-12p70 at 12 h, as compared both with the prechallenge and with PBS control values. No significant changes in the serum cytokines were recorded during the PBS controls (p > 0.2). Conclusions: These results support the evidence for an active involvement of the Th1 cells, neutrophils, monocytes, macrophages, epithelial cells and endothelial cells, upon cooperation of other cell types, in the immunological mechanism(s) underlying the DYAR. Copyright © 2012 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: Bottle-fed infants sometimes develop intestinal cow's milk allergy (ICMA). Because cow's milk-specific IgE antibody (CM-IgE) levels are normal, the lymphocyte stimulation test (LST) has been proposed as an alternative diagnostic test for ICMA. The present study evaluated the diagnostic value of LST in a large number of patients with ICMA in Japan. Methods: Ninety-six infants who developed intestinal symptoms after ingestion of cow's milk formula and showed remission of symptoms after elimination of this food were enrolled as patients with probable ICMA. Seventy-two subjects with normal CM-IgE levels and a positive result in an oral food challenge test (OFCT) for cow's milk formula were diagnosed with ICMA. Another 10 infants with normal CM-IgE levels and a negative OFCT result were diagnosed with nonspecific intestinal symptoms (NIS). The status of cell-mediated immunity against cow's milk proteins was estimated by LST for κ-casein. Results: In the 72 patients with ICMA (38 boys and 34 girls), the median age at onset was 9 days. Sixty-two of 72 (86.1%) patients with ICMA tested positive in the LST for κ-casein. In contrast, only 2 of the 10 NIS infants tested positive. The incidence of a positive LST result was significantly higher in the ICMA group than in the NIS group (p < 0.0001). The area under the receiver-operating characteristic curve for this test was as high as 0.856. Conclusions: This study strongly suggests that the LST for κ-casein is a useful diagnostic test for ICMA. Copyright © 2011 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: In patients with allergic bronchial asthma, different immunologic mechanisms may participate and lead to different types of asthmatic response to allergen challenge, such as immediate/early (IAR/EAR), late (LAR) or delayed asthmatic response (DYAR). Objectives: In 55 of 397 asthmatics, DYAR has been recorded (p < 0.001) and confirmed by repeated bronchial challenge with the same allergen (p < 0.001). DYAR began between 26 and 32 h, reached a maximum between 32 and 48 h and resolved within 56 h after the challenge. DYAR was associated with various clinical symptoms and diagnostic parameters having diverged from those recorded during the IARs/EARs and LARs. Methods: In 25 of 55 patients, repeated DYAR has been supplemented with the recording of leukotriene B4 (LTB4), LTC4, LTE4, prostaglandin D2 (PGD2), PGE2, PGF2α, thromboxane B2, lipoxin A4, eosinophil cationic protein, eosinophil-derived neurotoxin/eosinophil protein X, eosinophilic peroxidase, myeloperoxidase, histamine and tryptase in peripheral blood, and of LTC4, thromboxane B2, eosinophil-derived neurotoxin and 9α,11β-PGF2 in urine, before and up to 72 h after the bronchial allergen challenge, by means of enzyme-linked immunoassay (ELISA/EIA) or ImmunoCAP. Results: DYAR was accompanied by a significant increase in the plasma concentrations of LTB4 (p < 0.05) and myeloperoxidase (p < 0.05) at 24, 36 and 48 h after the challenge, whereas the plasma/serum or urine concentrations of the other factors did not demonstrate any significant changes (p > 0.05). Conclusions: These results would indicate an active and prominent involvement of neutrophils, in addition to the previously demonstrated role of the Th1 lymphocytes, in the clinical DYAR. Copyright © 2011 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: Using a T helper (Th)1/Th2 disease model, we previously showed that genetically determined Th development depends on dendritic cell-derived interleukin (IL)-1α. In Leishmania major infections, Th1 immunity develops if IL-1α is present during T cell priming, whereas at later time points, IL-1α worsens disease outcome. In the present study, we determined the role of IL-1α in other Th2-mediated diseases. Methods: BALB/c mice were subjected to delayed-type hypersensitivity (DTH) or ovalbumin (OVA)/alum-induced allergic asthma in the presence or absence of IL-1α. Results: In DTH, mice treated with IL-1α during sensitization with keyhole limpet hemocyanin (KLH)/alum developed decreased footpad swelling associated with elevated KLH-specific interferon-γ levels. In asthma, significantly decreased airway hypersensitivity responses (AHRs) were detected upon treatment with IL-1α during T cell priming. In contrast to control mice, IL-1α-treated mice showed reduced peribronchial inflammatory infiltrates. The bronchoalveolar lavage (BAL) fluid contained significantly decreased eosinophil numbers (approximately 50%), but 4 times more neutrophils. The BAL fluid of IL-1α-treated BALB/c exhibited reduced amounts of IL-5 and OVA-specific IgE serum levels. In contrast, IL-1α treatment at later time points after sensitization or during allergen challenge worsened AHR, had no effect on lung inflammation and BAL fluid cell composition. Furthermore, cytokine levels (IL-5, IL-13) and antigen-specific IgE were increased or unaltered under these conditions. Conclusion: Similarly to leishmaniasis, IL-1α administration during sensitization of Th2-mediated allergic reactions suppresses the course of disease by shifting the immune response towards Th1, whereas later treatments worsen disease outcome. Future studies will elucidate the therapeutic value of IL-1α in asthmatic patients. Copyright © 2010 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: The cytokine transforming growth factor-β(TGF-β) has important regulatory roles in the immune system. To investigate the role of intact TGF-β signaling during the contact hypersensitivity (CHS) response to a respiratory allergen, we exposed Smad3–/– mice to topical trimellitic anhydride (TMA). Methods: CHS was induced by topical application of TMA. The swelling of the TMA-exposed ears was analyzed, and lymph node, ear tissue and skin biopsies were collected for RNA isolation, histology and histochemical analyses. Lymph node cell proliferation was measured and blood samples were collected for analysis of TMA-specific immunoglobulin. Results: Topical TMA exposure resulted in increased mRNA expression of proinflammatory and suppressive cytokines (IL-1β, TNF-α, IL-6, IFN-γ, IL-4, IL-10, IL-17, IL-23, TGF-β), chemokines (CXCL9, CXCL10, CCL24) and chemokine receptors (CCR7, CCR8, CXCR2), increased numbers of CD3+ T cells in ear tissue, and lymphadenopathy in the Smad3–/– mice. The IL-10 result was confirmed at the protein level by immunohistochemistry. However, the ear-swelling response and infiltration of eosinophils, F4/80+ cells, CD11c+ cells and mast cells were similar in the Smad3–/– mice compared to their wild-type (WT) siblings. While TMA-specific IgE was induced equally in the WT and Smad3–/– mice, the concentration of TMA-specific IgG2a was significantly lower in the Smad3–/– mice. Conclusions: The Smad3 molecule contributes significantly to the regulation of the cytokine and chemokine network during the CHS response to TMA. The lack of Smad3 resulted in a potent Th2 shift, confirmed by strongly impaired IgG2a levels. Copyright © 2009 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: It has been thought that poly-L-lactic acid (PLLA) injections do not have inflammatory side effects. Recent evidence shows that local/regional/systemic delayed adverse effects may appear with its use.Objective: To evaluate the clinical complaints, treatment response and long-term follow-up of non-HIV patients with delayed immune-mediated adverse effects related to PLLA injections.Methods: Prospective, case series study of 10 patients with delayed adverse effects related to PLLA injections. The inclusion criterion was defined as the onset at least 6 months after PLLA use, with 1 or more of the following clinical signs: oedema, skin induration, swelling/tender nodules with or without discharge of pus or filler material. Several systemic manifestations were also included. Patients with immediate side effects were excluded. Patients underwent clinical management and long-term follow-up.Results: The average latency period to the onset of symptoms was 19.2 months (range: 6-60). Tender, inflammatory nodules and facial oedema were commonly seen. One case presented a systemic granulomatous disorder as a complication. After 50.2 months of average follow-up (range: 38-78), 5 patients are in remission, 4 have recurrent bouts and the last case has been lost to follow-up.Conclusion: Although infrequently, local and/or regional and/or systemic delayed and recurrent granulomatous reactions may complicate PLLA gel injections. [ABSTRACT FROM AUTHOR]

Background: Epoxy resins (ERs) are used in paints and other protective coatings, including flooring materials. Bisphenol A diglycidyl ether (BADGE) ERs (BADGE ERs) account for about 75% of the ERs used world-wide. ERs can cause both immediate and delayed allergic reactions, but immediate reactions are rare. Methods: Occupational asthma (OA) was diagnosed on the basis of a specific challenge test combined with the patient’s history of occupational exposure and respiratory symptoms. Results: A 39-year-old nonsmoking construction worker experienced dyspnea when laying ER-containing floors, but not in other situations. He also presented skin symptoms. IgE-mediated allergy to BADGE ER could be verified with both serum IgE antibodies and skin prick tests. The specific bronchial challenge test with BADGE ER caused an immediate asthmatic reaction. On patch testing, a positive reaction was provoked by BADGE ER. Conclusions: This is the first study on a patient exposed to BADGE ER with IgE-mediated immediate OA, based on a positive inhalation challenge test. If work-related respiratory symptoms develop when handling ERs, the possibility of OA should be recognized. Copyright © 2008 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: The T-cell-mediated contact hypersensitivity reaction (CHR) is thought to be involved in the pathogenesis of clinical cutaneous disorders including atopic dermatitis. A novel diaminouracil derivative, CX-659S, has been reported to have an inhibitory activity against picryl chloride (PC)-induced CHR when administered either orally or percutaneously. The inhibitory effect of topical CX-659S was assessed in three CHR models in the present study. In addition, to elucidate the mechanism of action of this compound, we examined the effect of CX-659S on the expression of messenger RNAs for proinflammatory cytokines after elicitation in PC models. Methods: For the in vivo evaluation of the efficacy of CX-659S, we used PC- or oxazolone-induced CHR in mice and 2,4-dinitrochlorobenzene (DNCB)-induced CHR in guinea pigs. CX-659S was topically applied immediately after the hapten challenge in each model. To assess the effect on gene expression of cytokines, we used the reverse transcriptase-polymerase chain reaction (RT-PCR), a semiquantitative technique with specific primers. Results: Topical CX-659S dose-dependently inhibited ear swelling at 24 h after the challenge in the two mouse models. This inhibitory effect was histologically confirmed in the PC model. Topically applied CX-659S also inhibited erythema and edema formation 24 h after challenge in the guinea pig model. CX-659S inhibited the expression of mRNA for proinflammatory cytokines IL-1β and TNF-α in vivo. Conclusions: Topically applied CX-659S showed significant inhibitory activities against CHR models both in mice and in guinea pigs. Inhibition profiles of CX-659S toward mRNA expression for proinflammatory cytokines corroborated these findings. CX-659S thus could be a useful therapeutic agent for allergic cutaneous disorders such as allergic contact dermatitis and atopic dermatitis.Copyright © 2000 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: Experiments were aimed to test the cross-reactivity of immune Th1 cells that mediate contact hypersensitivity (CHS) or inflammatory bowel disease (IBD) to TNP in the mouse. Methods: CBA/J mice were immunized either epicutaneously or intrarectally with TNP and after appropriate time intervals were challenged with antigen in a crossed manner. The CHS reaction was measured by the ear swelling test. IBD was quantified by increase of colon weight and myeloperoxidase level. Both reactions were confirmed histologically. In passive-transfer experiments, mesenteric lymph node cells of animals sensitized intrarectally and peripheral lymph node and spleen cells of mice immunized epicutaneously were used. In some experiments, before being immunized mice were made either unresponsive to the TNP hapten by induction of suppressor T cells, or resistant to suppression after induction of upregulatory T cells. Results: Irrespective of the mode of sensitization upon appropriate challenge with antigen all mice developed a good CHS reaction as well as significant IBD. This cross-reactivity could be passively transferred by immune cells. In mice in which antigen-specific down- or upregulatory cells were induced before sensitization both CHS and IBD to TNP were modulated accordingly. Conclusion: TNP hapten deposited on skin or on mucosal surfaces induces effector cells that recognize antigen independent of its tissue localization, and produce a local inflammatory reaction. TNP-specific up- and downregulatory cells, shown before to regulate the CHS reaction, similarly modulate the generation and development of hapten-induced IBD.Copyright © 2000 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: We have uncovered a role for B–1–B–cell–produced IgM antibody, in the initiation of contact sensitivity (CS) in mice. CS and delayed–type hypersensitivity (DTH) involve recruitment of T cells to the tissues, to be activated by antigen–presenting cells (APC), and then make cytokines. Little is known about low recruitment is initiated. In CS, soon after immunization, the unique B–1 cell subset, responsible for the formation of most IgM, is activated to produce antigen (Ag)–specific IgM for export to tissues. IgM forms complexes with challenge Ag, activating the classical complement (C) pathway, generating C5a, to activate endothelium directly, or indirectly via C5a receptors (R) on mast cells and platelets, that release vasoactive amines (serotonin) and cytokines (TNF–α). These act together to induce vasodilatation, vascular permeability and expression of endothelial adhesion molecules to promote optimal T cell recruitment. Methods and Results: New findings that established this pathway include: (1) absent CS response in C–deficient, or C–inhibited mice; (2) local generation of C5a in CS tissue extracts; (3) absent CS in C5aR[sup –] /[sup –] mice; (4) decreased CS in B cell and B–1–cell–deficient mice, and (5) reconstitution of CS by transfer of B–1 cells, or hapten–specific IgM. Conclusion: These findings indicate that the B–1 subset producing Ag–specific IgM is required early in CS to activate C, to induce vasoactive mediators that initiate local T recruitment. [ABSTRACT FROM AUTHOR]

Background: The exposure of human skin to leaves and branches of litre (Lithraea caustica), a Chilean endemic tree, induces a severe contact dermatitis characterized by swelling and pruritus in susceptible individuals. The allergenic priniciple of litre is 3–pentadecyl (10–enyl) catechol (litreol), which is structurally similar to the allergens isolated from poison oak and poison ivy. All of them belong to a family of compounds named urushiols. As a proelectrophilic allergen, litreol must be intracellularly activated before modifying proteins of individuals exposed to it. As a result, self–peptides derived from litreol–modified intracellular proteins would be presented in the context of class I MHC molecules. We hypothesized that CD8+ T lymphocytes would play a major role during the effector phase of the immune response induced by those modified peptides. In order to test this hypothesis, we investigated the cellular immune response to litreol in Balb/cJ mice. The role of the different lymphocyte subpopulations in this response was assessed by immunodepleting mice of CD4+ or CD8+ T lymphocytes using specific monoclonal antibodies (mAbs). We report the observation that the contact dermatitis induced by litreol has two components: a primary response which does not require TCRαβ+ T cells, and a secondary response mediated mainly by CD8+ T cells and regulated by CD4+ T cells. Our results show that CD8+ lymphocytes play a central role as effectors of the secondary response to litreol. Furthermore, our data suggest that two functionally different CD4+ T subpopulations serve as regulators of the CD8+ T cell function: a CD4+ T helper population sensitive to a low dose of the depleting mAb, and CD4+ T suppressor population which is eliminated only with a high dose of depleting mAb. [ABSTRACT FROM AUTHOR]

A 73-year-old man with mild inactive interstitial pneumonitis and non-small cell bronchogenic carcinoma developed a cell-mediated hypersensitivity pneumonitis within 15 days following a second exposure to paclitaxel. Histological features of transbronchial lung biopsy were consistent with interstitial pneumonitis. Bronchoalveolar lavage showed increased lymphocytes and eosinophils, and decreased helper/suppressor T lymphocyte ratio. Leukocyte migration inhibitory test was positive for paclitaxel. These results support the possibility that paclitaxel-induced pneumonitis is due to delayed type hypersensitivity; they also support the hypothesis of a central role of T lymphocytes in drug-induced pneumonitis. [ABSTRACT FROM AUTHOR]

Tuberculin reactivity decreases with age despite epidemiologic evidence that the elderly are more likely to have been infected. Whether this phenomenon is due to lack of antigenic stimulus or host inability to mount a delayed type hypersensitivity (DTH) response is unclear. In order to determine if the DTH response to tetanus toxoid in an exposed population is a useful tool to understand the phenomenon of lack of tuberculin reactivity in the remotely exposed elderly, a trial of skin testing was undertaken. Seventy-seven residents of a Veterans Affairs domiciliary were skin-tested using solutions of tetanus toxoid, candida and mumps skin test antigen. The 35 subjects who had negative reaction to the tetanus skin test were randomized into two groups: one which received tetanus vaccination before repeat skin testing and one which did not. Positive skin test reactions occurred in 42 patients to tetanus toxoid, 44 to mumps and 37 to candida. Of the 35 randomized, 27 were available for repeat skin tests. None reacted to the repeat tetanus skin test although 5 reacted to other antigens to which they had previously been nonreactive. Tetanus toxoid was equal to other antigens in its ability to elicit a DTH response originally; however antigenic stimulation with vaccination did not elicit positive skin test in nonreactors. Lack of DTH response to tetanus toxoid in recently vaccinated patients implies that nonresponse was secondary to host factors rather than lack of antigenic stimulation. [ABSTRACT FROM AUTHOR]

In this study we first investigated the cellular immune responses in mice with chronic liver injury induced by delayed-type hypersensitivity to picryl chloride (PCl). A continuous reduction, after week 3 of liver injury, was observed in the level of PCl-induced contact sensitivity but not in sheep red blood cell-induced footpad reaction, suggesting the presence of PCl-specific suppression. When spleen cells from mice whose liver had been injured for 1 week were systemically transferred into syngeneic recipients with the liver injury, the elevation in serum lactic dehydrogenase and the decrease in alkaline phosphatase and albumin levels in recipient mice were significantly exacerbated. However, when the liver damage in the donor mouse was allowed to proceed for 3, 5 or 7 weeks, biochemical changes in recipients were reduced to near normal levels. A flow-cytometric assay demonstrated that the number of CD4+ T cells in both spleen cells and liver nonparenchymal cells decreased dramatically during the late phase of liver injury, while CD8+ counts did not. These findings suggest that CD4+ and CD8+ T lymphocytes may contribute to the positive and negative regulation, respectively, of the early and late phases in the chronic development of liver injury. [ABSTRACT FROM AUTHOR]

Provides information on a study which used an extremely sensitive on-line RT-PCR approach to measure mRNA induction. Cause of allergic contact dermatitis; Situation when proliferative responses of lymphocytes of fragrance-allergic patients are increased; Difficulty of measuring constitutive expression using conventional RNA techniques.

Examines the cytokine profile expressed in acute versus spontaneous allergic contact dermatitis lesions on the mRNA and protein level. Presence of T lymphocytes in allergic inflammation; Importance of T lymphocytes; Characteristic for acute lesions of atopic dermatitis.

Describes a case of allergic reactions to epoxy and metal compounds following pacemaker implantation. Patient characteristics; Information on epoxy as an allergen; Treatment administered to the contact dermatitis.