Characterisation of T-cell Response to Keyhole Limpet Hemocyanin (KLH) and Tuberculin Purified Protein Derivative (PPD)

This is an exploratory study to develop methodologies for the assessment of T-cell mediated therapies via skin immune challenges studies in healthy volunteers. The study will investigate what is the most appropriate; skin challenge agent, time and methodology to sample and characterise T-cells in the delayed type hypersensitivity (DTH) skin reaction. The skin challenge agents to be used in this study will be the neoantigen Keyhole Limpet Hemocyanin (KLH) and recall antigen Tuberculin Purified Protein Derivative (PPD). Part A of the study will assess an intradermal (ID) KLH challenge in three subjects to assess if the immune response to KLH is initiated by the innate or adaptive immune system. Each subject will receive one ID dose of 0.1 milligram (mg) KLH and will be assessed for a skin inflammatory response. Part B of the study will assess repeat ID challenges 28 days apart; the objective will be to characterise the T-cell response to each challenge and the kinetics of that response.

For Cohorts 1A and 1B, 16 subjects will receive an initial subcutaneous (SC) 5 mg dose of KLH. Fifteen days later the subjects will receive 0.1 mg ID KLH dose and the response will then be assessed 48 and 120 hours after the initial challenge. The ID KLH challenge will then be repeated 28 days later and the response will be assessed at 48 hours (Cohort 1A, 8 subjects) and at 120 hours (Cohort 1B, 8 subjects) post challenge. For Cohort 2, a repeat challenge of either 2 tuberculin Unit (TU) or 10 TU ID PPD will be administered 28 days apart, to 8 subjects. The first challenge response will be assessed 48 and 120 hours post challenge. The second challenge will be administered 28 days after the first and will be assessed at the same timepoints. The repeat challenge 28 days later will allow an intra-subject analysis and will determine if a subject can be used as their own control. Part C of the study will assess repeat ID challenges of PPD and PBS; the objective will be to characterise the T-cell response to each challenge and the kinetics of that response. For Cohort 1, 6 subjects will receive a 0.1ml ID dose of PBS and another dose 24 hours later. Each challenge will be assessed 48 hours post challenge. Approximately 2 subjects will have an assessment of their normal skin as a control. For Cohort 2, a repeat challenge of either 2TU or 10TU ID PPD will be administered 28 days apart, to 6 subjects. The first challenge response will be assessed 48 post challenge. The second challenge will be administered 28 days after the 1st and will be assessed at the same timepoint. The repeat challenge 28 days later will allow an intra-subject analysis and will determine if a subject can be used as their own control.

The total duration of this study for Part A is 14-18 days plus up to 30 days screening. The total duration of this study for Cohort 1A is 56-60 days plus up to 30 days screening. The total duration of this study for Cohort 1B is 59-63 days plus up to 30 days screening. The total duration of this study for Cohort 2 if 2TU is used is 45-49 days plus up to 30 day screening. The total duration of this study for Cohort 2 if 10TU is used is 48-51 days plus up to 30 days screening. The total duration of this study for Part C Cohort 1 is 15-19 days plus up to 30 day screening. The total duration of this study for Cohort 2 if 2TU is used is 42-46 days plus up to 30 day screening. The total duration of this study for Cohort 2 if 10TU is used is 45-49 days plus up to 30 days screening.


Eligibility Criteria:
Inclusion Criteria:

* Male or female between 18 and 55 years of age inclusive, at the time of signing the informed consent.
* Healthy as determined by a responsible and experienced physician, based on a medical Evaluation.
* Body weight \>= 50 kg and body mass index (BMI) within the range 19.5 to 29.9 kilogram/meter squared (inclusive).
* Female subjects of non-child bearing potential. Females of child bearing potential are eligible to enter if they are not pregnant and willing to use protocol-specified methods of contraception to prevent pregnancy.
* Male subjects with female partners of child-bearing potential must agree to use one of the contraception methods from the time of the first dose of challenge agent until follow-up.
* Capable of giving written informed consent.
* Alanine aminotransferase (ALT) alkaline phosphatase and bilirubin \<or=1.5x upper limit of normal (ULN).
* Normal electrocardiogram (ECG) measurements. Average QT duration corrected for heart rate by Fridericia's formula (QTcF) \<450 millisecond (msec).
* Part B and C cohort 2 only: Subjects with a history of Bacillus Calmette Guérin (BCG) vaccination as evidence by either a BCG scar and verbal confirmation of BCG vaccination or documented medical history of a BCG vaccination with or without a BCG scar

Exclusion Criteria:

* Prior medical history of anaphylaxis, severe adverse reaction to vaccines, allergy to shellfish, asthma (excluding childhood asthma), allergic rhinitis or atopic dermatitis, severe adverse reaction to local anaesthetic, previous tuberculosis infection.
* Current treatment with beta-blockers or angiotensin converting enzyme (ACE) inhibitors.
* History of sensitivity to any of the study challenge agents or components thereof or a history of drug or other allergy that, in the opinion of the investigator or GlaxoSmithKline (GSK) Medical Monitor, contraindicates their participation.
* Received live, attenuated or recombinant vaccine(s) within 2 months of the first KLH or PPD injection or will require vaccination prior to the follow-up visit.
* Part B and C cohort 2 only: From a high risk area of the world for tuberculosis or have close family members with confirmed Mycobacterium tuberculosis (MTB).
* Antibiotics or antiviral therapy after a serious illness within 30 days of study entry.
* Immunodeficiency or autoimmunity, assessed by medical history.
* Presence of tattoos, naevi or other skin abnormalities such as keloids (or history of keloids) that may, in the opinion of the investigator, interfere with study assessments.
* Use of nicotine patches on the arm at screening that would interfere with the injection sites.
* Subjects participating, within 7 days of screening, in recreational sun-bathing, or use of sun-bed, on the area of the skin from wrist to shoulder inclusive.
* The subject has a phobia to needles or minor surgical procedures.
* Current or chronic history of liver disease, or known hepatic or biliary abnormalities (with the exception of Gilbert's syndrome or asymptomatic gallstones).
* History of regular alcohol consumption within 6 months of the study.
* Use of prescription drugs or non-prescription drugs, including NSAIDs, if in the opinion of the Investigator the medication will interfere with the study procedures or compromise subject safety. Subjects must not currently take any of the following: topical steroid cream on the arms, oral or systemic steroids or any other immune-modulators.
* A positive pre-study Hepatitis B surface antigen or positive Hepatitis C antibody result within 3 months of screening
* A positive pre-study drug/alcohol screen.
* A positive test for human immunodeficiency virus (HIV) antibody.
* Pregnant or lactating females.
* Donation of more than 500 milliliter (mL) blood within a 56 day period.
* Participated in a clinical trial and has received an investigational product within the following time period prior to the first dosing day in the current study: 30 days, 5 half-lives or twice the duration of the biological effect of the investigational product (whichever is longer)
* Exposure to more than four new chemical entities within 12 months prior to the first dosing day.
* Part A and part B Cohort 1: The subject has received KLH SC or ID in the past.