Immunity Project

Experiment Update #3

Return to blog home | Posted in: Blog on Apr 10, 2014 by Naveen Jain

We’ve completed the human blood experiments described in our previous blog post.  Results:

In vitro experiment:

Overview

Our vaccine is intended to “teach” the human immune system to act like that of an HIV controller (a person who has a natural immunity to the HIV virus).  The goal of our in vitro experiments is to successfully “vaccinate*” human blood in a test tube.  The step-by-step process for this experiment is as follows:

  1. Draw blood from a human subject who has a specific HLA type (A02.1).  An HLA type is a type of immune system.  This HLA type corresponds to a specific target on the HIV virus.  In other words, the virus target we are using is the one that is matched to people with this HLA type.
  2. Separate a specific type of white blood cell (dendrocytes) from the blood sample given, culture those cells, and add our vaccine prototype to them.  The objective is to get the dendrocytes to phagocytose our vaccine microspheres.  In other words, we want the dendrocytes to “eat” the microspheres like they do in this video  from one of our previous experiments.
  3. Separate another type of white blood cell (T cells) from the blood sample given, culture those cells, and add in the dendrocytes from step 2 to them.  The objective is to get the dendrocytes to “teach” the T cells about the HIV virus targets contained in our vaccine microspheres.
  4. Then we separate more T cells (called CD4 cells) from the blood sample given, culture those cells, and infect them with HIV.
  5. Combine the HIV infected CD4 cells from step 4 and the T cells from step 3 in a test tube to see if the t cells can kill the HIV infected cells.  We measure the result by testing for markers for cell death, and markers for HIV virus suppression (p24 antigen).

Results

  • Subject 1 – We successfully vaccinated this subject’s blood sample and got statistically significant data that shows it can suppress HIV in laboratory-infected cells.  We consider this a positive result.  It’s encouraging but requires confirmation.
  • Subject 2 – This subject’s blood sample had very high negative control signal (essentially “noise”) and was un-interpretable.  We consider this a negative result.

Mouse experiments:

Overview

Our vaccine is intended to “teach” the human immune system to act like that of an HIV controller (a person who has a natural immunity to the HIV virus).  The goal of our mouse experiments is to successfully vaccinate human blood in a mouse.  The step-by-step process for this experiment is as follows:

  1. Draw blood from a human subject who has a specific HLA type (A02.1).  An HLA type is a type of immune system.  This HLA type corresponds to a specific target on the HIV virus.  In other words, the virus target we are using is the one that is matched to people with this HLA type.
  2. Separate all white blood cells from the human blood sample given and inject those cells into the mouse.
  3. Inject our vaccine into the mouse.  The objective is to get the human dendrocytes contained within the white blood cell sample in step 2 to phagocytose our vaccine microspheres in the mouse.  In other words, we want the dendrocytes to “eat” the microspheres like they do in this video from one of our previous experiments.
  4. Draw white blood cells from the mouse.
  5. Separate a specific type of white blood cell (T cells) from the white blood cells drawn in step 4 and culture those cells.
  6. Separate more T cells (called CD4 cells) from the blood sample given in step 1, culture those cells, and infect them with HIV.
  7. Combine the HIV infected CD4 cells from step 6 and the T cells from step 5 in a test tube to see if the T cells can kill the HIV infected cells.  We measure the result by testing for markers for cell death, and  markers for HIV virus suppression (p24 antigen).

Results

  • Round 1 (sixteen C57BL/6 mice) – This experimented was halted after step 2 as this group of mice failed to fully integrate the transfused human blood cells.  We consider this a negative result.
  • Round 2 (fourteen C57BL/6 mice) – This experiment was halted after step 2 as this group of mice failed to fully integrate the transfused human blood cells.  We consider this a negative result.
  • Round 3 (fourteen JAX NOD “scid” mice) – This group of mice fully integrated the transfused human blood cells but no vaccination event occurred.  We think this is because adding external components to humanized mice introduces the risk that those components will perform sub optimally.  We consider this a negative result.

We’ve decided against pursuing further mice experiments.  While we think we could eventually make a humanized mouse model work, it’s clear that we’d likely need a few iterations to achieve positive results.  Unfortunately, these experiments are expensive and take significant time to complete, so it’s impractical to move forward with them.

Next Steps:

The positive result in our first in vitro experiment is encouraging, but we’d like to have additional positive results before we meet with the FDA.  To accomplish this goal we’re moving forward with confirmatory experiments.  Our next round of in vitro experiments – Round 2 – involves five subjects and will be completed by May 26th.  Due to the inexpensive nature of these experiments, we’re able to use the remaining funds from our crowd funding campaign to complete them.

Round 2 in vitro experiments:

In this round of in vitro experiments we’ll be working on optimizing the model as well as confirming our previous positive result.  Last week we completed our experiment design and obtained all of the necessary supplies.  We’re currently drawing blood from our five volunteers.

We’re continuing to iterate rapidly and make good progress.  We’re honored to have your support and look forward to sharing the results of our new in vitro experiments with you as soon as possible.  Thank you again for helping us make Immunity Project happen.

* Our experiment tests for T-cell activation but not immune system response memory.  We will test for memory in our human clinical trial.