Active clinical trials for "Hypersensitivity, Delayed"

This study is being conducted to see effectiveness of auto-inoculation of a wart in multiple viral warts. Patients with recurrent, multiple warts of all types, are being recruited for the study. A wart is excised, minced and then inoculated in a subcutaneous pocket made on the volar aspect of forearm. Patients are to be reviewed after every 4 weeks to note any reduction in number warts.

The treatment of allergic contact dermatitis (ACD) can be unsatisfactory, and that other skin diseases such as atopic dermatitis have an increased likelihood of ACD, improved systemic treatments are needed. This research study explores the effectiveness of Baricitinib in treating Delayed-Type Hypersensitivity (allergic) versus Irritant Skin reactions. Subjects for this study need to be healthy males between the ages of 18 and 40. This study will evaluate this by injecting antigens as well as applying them on top of the skin to the forearm then measure the effects of Baricitinib by skin and blood testing.

This dose finding, multi-cohort study is designed to evaluate the safety and efficacy of intradermally-injectedTNX-2100, synthesized SARS-CoV-2 peptide antigens and assess the presence and magnitude of DTH reactions.

To determine the frequency of delayed-type hypersensitivity (DTH) reactions in HIV-positive patients to two doses of two envelope glycoprotein antigens prepared differently. To determine whether patients who have previously demonstrated a DTH response to intradermal MGStage HIV-1 gp160 IIIB baculovirus (MicroGeneSys) have a reproducible response to a repeat injection of gp160 and whether there is cross-reactivity to intradermal HIV-1 rgp160 IIIB vero cell expressed (Immuno-AG). PER 4/5/95 AMENDMENT: To also determine whether patients who respond to HIV-1 rgp160 IIIB baculovirus (MicroGeneSys) have cross-reactivity to intradermal skin tests of HIV-1 rgp160 MN (Immuno-AG). Previous studies in individuals immunized with gp160 suggest that a skin test response in immunized patients can be used as a surrogate marker for new proliferative and cytotoxic responses induced by vaccination.

Whilst validated tools exist to enable inpatient penicillin assessment and de-labelling, limited evidence is available regarding the safety and efficacy in the outpatient clinic. The ability to deliver point-of-care penicillin allergy testing for a large cohort of patients, without skin testing, will improve patient access to testing and utilization of preferred penicillin antibiotics.

To determine the safety of intradermal gp160 in HIV seropositive individuals who are asymptomatic and have a relatively intact immune system. To determine whether there is evidence of a delayed-type hypersensitivity (DTH) response (a "positive" skin test) in these patients, and also the dose of gp160 that elicits a delayed-type hypersensitivity (DTH) response. Early immunity to HIV may play an important role in the long interval between virus infection and the onset of clinical disease. Immune responses have been demonstrated in HIV-infected individuals within weeks to months of infection. Although none of these responses has been shown to be protective, it is possible that boosting anti-HIV immune responses through immunization may slow the progression of HIV infection. DTH responses to HIV-derived recombinant envelope glycoprotein could provide a means of measuring an important immune function in infected patients, and serve as an easily measured surrogate marker of cellular immunity. In addition to eliciting local, cutaneous DTH responses, intradermal inoculation of skin test antigens may be immunogenic, resulting in new antibody production and cellular immune responses. This study allows direct comparison of gp160 administered intradermally with alum-adjuvanted intramuscular preparation with respect to immunogenicity in HIV seropositive patients.

This study will be conducted in 2 cohorts. In Cohort A, approximately 40 subjects will participate in a single-center, open-label, non-randomized, parallel-group trial to investigate the molecular mechanisms involved in delayed-type hypersensitivity (DTH) to various antigens and assess the most appropriate skin challenge antigen to study the effect of systemic treatments on T cells. Following evaluation of the results in Cohort A, approximately 20 healthy volunteers will be enrolled in Cohort B. This cohort will be a single-center, double-blind, randomized, two-arm, placebo-controlled study to evaluate the effect of corticosteroid treatment on the molecular and cellular phenotype of delayed hypersensitivity response to one if the antigens previously studied in Cohort A.

Ultraviolet (UV) light is part of normal sunlight and has many effects on human skin and health. One of the harmful effects of long-term UV light exposure is that it can cause skin cancer. The mechanism by which UV light causes skin cancer is not entirely understood. One of the ways UV light causes cancer is by modifying DNA molecules in the cells of the skin. Another mechanism involved in cancer formation by UV light is immunosuppression. By this mechanism, UV light inactivates cells of the immune system of the skin. The immune cells are responsible for the detection and destruction of foreign substances and organisms such as bacterias and viruses but they also recognize and destroy cancer cells. UV light is known to prevent cells of the immune system to destroy cancer cells. In laboratory experiments, a medication called denosumab has been shown to diminish the inhibition of ultraviolet-induced suppression of skin immunity. In other words, this medication could block the effect of UV on cells of the immune system and might allow patients taking this drug to be better protected from skin cancer. The objective of this study is to test whether denosumab blocks the immunosuppressive effect of UVB light in healthy subjects. This study is divided into two stages. In the first stage, ten subjects (Cohort 1) will be sensitized to diphenylcyclopropenone (DPCP), a topical sensitizer commonly used for the treatment of alopecia areata and cutaneous warts. By reexposing the subjects to DPCP in incremental doses, dose-response levels of cutaneous hypersensitivity reactions in normal skin will be obtained. This will allow comparison of the normal levels of DPCP-induced cutaneous hypersensitivity (CHS) reaction in non UV-exposed skin (Cohort 1) to the CHS obtained from the two UVB-exposed experimental groups of Cohort 2. In the second stage of the study, 20 subjects (Cohort 2) will be exposed to an immunosuppressive dose of ultraviolet B (UVB) 24 hours prior to DPCP sensitization. This is expected to result in the abolition of CHS upon rechallenge with DPCP. In order to assess whether denosumab can reverse UVB-induced immunosuppression, the subjects will have previously been randomized to receive a single 1mL injection of either 60 mg denosumab (group A; 10 subjects) or 1 mL saline (group B; 10 subjects) two weeks before UVB exposure. CHS reactions elicited by DPCP rechallenge will be compared between the denosumab and saline groups.

BCG vaccination has been found to provide greater protection against TB in the UK than in Malawi. This study compares immune responses in BCG-vaccinated and unvaccinated teenagers and young adults in Malawi and in the UK.