Monday, April 2, 2012

4 Viral Genetics VGV-L Candidate For Treating Chronic Lyme Disease

On Friday I posted about the use of Filgrastim and Ceftriaxone for treating persisting symptoms in a Lyme disease case study as well as the use of Rituximab for treating CFS/ME. I also touched upon Viral Genetics' VGV-L or targeted peptide therapy for treating chronic Lyme disease, and wanted to write an entry about this treatment on its own.

What I can tell you is to some degree limited by the fact that VGV-L's exact design and mechanism is proprietary in nature, so I can only report based on what the researchers and Viral Genetics choose to disclose. But hopefully, what I post here and future publications by Dr. Karen Newell Rogers will shed some light on the matter.

Dr. Karen Newell Rogers from Texas A & M is in the middle of contributing to the following three papers which seem to have a relationship between VGV-L and chronic Lyme disease:
  • S. Harris, E. W. Newell, R. P. Tobin, C. P. Harvey, N. Kurzman, E. M. Hechinger, P. Cipriani, and M. K. Newell. 2010. Comparative Analysis of Peptide Binding, MHC alleles, and B cell activation in patients meeting CDC criterion for Chronic Lyme Disease. (manuscript in preparation).
  • E. Connick, R. Schlichtemeier, J. Folkvord, R. Tobin, C. P. Harvey, and M. K. Newell. 2010. TLR activation of human peripheral blood B cells can be reversed by peptide treatment. 2010. Manuscript in preparation.
  • Cabrera, J. and M. K. Newell. 2010. Polyclonal TLR-induced B cell activation is controlled by Peptide-dependent B cell death (manuscript in preparation). 
All three in preparation, but I think they are tightly related to the same research and stem from this previous publication:

 M. K. Newell, R. P. Tobin, J. H. Cabrera, M. B. Sorensen, A. Huckstep, E. M. VillalobosMenuey, M. Burnett, E. McCrea, C. P. Harvey, A. Buddiga, A. Bar-Or, M. S. Freedman, J. Nalbantoglu, N. Arbour, S. S. Zamvil, and J. P. Antel. 2010. TLR-Mediated B Cell Activation Results in Ectopic CLIP Expression that Promotes B Cell-Dependent Inflammation. Journal of Leukocyte Biology.
Online e-Pub. July 14, 2010.

 Link to free full text this publication: http://www.ncbi.nlm.nih.gov/pubmed/20631258

Originally, I found one patent for this technology online:

http://www.faqs.org/patents/app/20100166789

In this patent, the portion attributed to Lyme disease states:
 "[0116] It is believed according to the invention that Borrelia burgdorferi also produces a Toll ligand for TLR2. Replacement of the CLIP on the surface of the B cell by treatment with a thymus derived peptide with high affinity for the MHC fingerprint of a particular individual, would result in activation of the important Tregs that can in turn cause reduction in antigen-non-specific B cells. Thus treatment with thymus derived peptides could reactivate specific Tregs and dampen the pathological inflammation that is required for the chronic inflammatory condition characteristic of Lyme Disease. With the appropriate MHC analysis of the subject, a specific thymus derived peptide can be synthesized to treat that subject. Thus individuals with all different types of MHC fingerprints could effectively be treated for Lyme disease."
However, I just found out that there are additional patents on this technology of which I was previously unaware. These patents contain a great deal of detail about what these targeted peptides can do and their effect on polyclonal B cells:

http://www.faqs.org/patents/app/20090258027
http://www.faqs.org/patents/app/20100034839
http://www.faqs.org/patents/app/20100166782
http://www.faqs.org/patents/app/20110118175

In addition to the above published paper on CLIP expression, Viral Genetics published the following excerpt in its research newsletter which explains what VGV-L does for HIV in easy-to-understand terms - substitute "Lyme disease" for "HIV" here:
"The conventional approach to HIV vaccines, for example, is to develop therapeutic vaccines to stimulate immune system response. The problem with the conventional approach is that the infected cells are camouflaged and not visible to the body’s immune system. The body’s powerful T-cells are unable to seek out and destroy the infected camouflaged cells because they cannot recognize that the cell is infected.

To understand the issue, think of the Klingon space ship on Star Trek that has its cloaking device activated. The U.S.S. Enterprise has no way of knowing where the enemy is in space. The only hope it has in winning the battle is for the Klingon vessel to be de-cloaked and, once revealed, use their ammunition to destroy it. What’s worse in the case of HIV is that while the infected cell is cloaked, it is also effectively setting off an alarm that triggers the immune system to create inflammation. Why is this important? It turns out that this inflammation is critical for allowing the HIV virus to spread to even more cells.

Many other viruses and bacteria also trigger inflammation but, unlike HIV, the inflammation does not necessarily allow or facilitate the spread of the virus or bacteria itself. * However, in these cases, the inflammation itself is harmful because it creates a hostile and inflamed environment that provides the necessary components for a potential autoimmune reaction that can cause the immune system to attack and damage one’s own body. Viral believes that diseases such as Lyme Disease, Multiple Sclerosis and others involve this inflammatory mechanism.

To use the Star Trek metaphor, what Dr. Newell Rogers has developed with TPT is a de-cloaking device for the body’s immune system to use in its pursuit of invaders. Through the development and use of computational biology programs and databases, Dr. Newell Rogers and her team have created a way to remove the camouflage that is cloaking the infected cells, flagging them with custom peptides that allow the body’s immune system to seek out and destroy them.

The key discovery of the TPT platform is that a self-peptide (in other words, one that is naturally produced and a healthy part of one’s normally functioning immune system) called ―CLIP2 that was until now thought only to exist primarily inside certain immune system cells, is sometimes displayed on the outside of cells, thus leading to harmful inflammation. Dr. Newell Rogers discovered that the products of some pathogen invaders such as viruses and bacteria, when picked up on the surface of certain immune system cells, sometimes incorrectly cause those cells to display CLIP externally (i.e. ―ectopically).

Normally, when an invader strikes, this process may promote needed inflammation early in infection, but it is quickly controlled when a more specific, immune response takes over, allowing a highly-targeted immune response to be marshaled against the pathogen. However, when CLIP is improperly displayed, displayed for too long or displayed chronically, the immune system is marshaled to promote a broad and unspecified inflammation without the specific targeting, leaving open the possibility that this inflammation actually turns against one’s own cells. Replacing CLIP is the focus of Viral’s Targeted Peptides because it turns off the harmful alarm."
Read more from the source - including about individual MHC genetic profiles here:
http://www.viralgenetics.com/investors/press-releases/Research_2.0_Report_Feb1_2011.pdf

One thing which I have thought of (and heard a few patients mention in passing) is that this candidate drug is only for treating inflammation and would only address an autoimmune angle relating to chronic Lyme disease.

However, this is not the case:

If you read the full patents, VGV-L's technology works not only to reduce inflammation, it also works to rebalance the immune system so that it is focused on fighting infection in a targeted manner. And in terms of treatment with VGV-L, patients may not just receive VGV-L alone - but also receive a bacterial antigen and antibacterial (possibly also antiparasitic and/or antiviral)  therapy concurrently to treat their condition.

Refer to this patent: http://www.faqs.org/patents/app/20110118175.

Here is the excerpt from the patent concerning the treatment of infections using this technology - including Lyme disease:
[0169] Bacterial diseases that can be treated or prevented by the methods of the present invention are caused by bacteria including, but not limited to, mycobacteria, rickettsia, mycoplasma, neisseria, Borrelia and legionella.

[0170] Although Applicant is not bound by a specific mechanism of action it is believed that the CLIP inhibitors of the invention displace CLIP from MHC class I and cause down regulation of Treg activity and/or activation of effector T cells such as γδT cells. Downregulation of regulatory function of Treg activity prevents suppression of the immune response and enables the subject to mount an effective or enhanced immune response against the bacteria. At the same time the Treg cell may shift to an effector function, producing an antigen specific immune response. Thus, replacement of CLIP with a peptide of the invention results in the promotion of an antigen specific CD8+ response against the bacteria, particularly when the peptide is administered in conjunction with a tumor specific antigen. Activation of effector T cells also enhances the immune response against the bacteria, leading to a more effective treatment.

[0171] One component of the invention involves promoting an enhanced immune response against the bacteria by administering the compounds of the invention. The compounds may be administered in conjunction with an antigen to further promote a bacterial specific immune response. A "bacterial antigen" as used herein is a compound, such as a peptide or carbohydrate, associated with a bacteria surface and which is capable of provoking an immune response when expressed on the surface of an antigen presenting cell in the context of an MHC molecule. Preferably, the antigen is expressed at the cell surface of the bacteria.

[0172] The compounds of the invention may be used in combination with anti-bacterial agents. Examples of such agents to treat bacterial infections include, but are not limited to, folate antagonists (e.g., mafenide, silver sulfadiazine, succinylsulfathiazole, sulfacetamide, sulfadiazine, sulfamethoxazole, sulfasalazine, sulfisoxazole, pyrimethoamine, trimethoprim, co-trimoxazole), inhibitors of cell wall synthesis (e.g., penicillins, cephalosporins, carbapenems, monobactams, vacomycin, bacitracin, clavulanic acid, sulbactam, tazobactam), protein synthesis inhibitors (e.g., tetracyclines, aminoglycosides, macrolides, chloramphenicol, clindamycin), fluoroquinolones (e.g., ciproloxacin, enoxacin, lomefloxacin, norfloxacin, ofloxacin), nalidixic acid, methenamine, nitrofurantoin, aminosalicylic acid, cycloserine, ethambutol, ethionamide, isoniazid, pyrazinamide, rifampin, clofazimine, and dapsone.
I don't know entirely what the researchers intend to use as a bacterial antigen... An Osp? They are suggesting a peptide or carbohydrate, though, and not a highly immunogenic lipoprotein from the cell's outer membrane - even though that's what I think they would have to use if they were to use an antigen. Reading ahead, though, there is the potential that any of a number of Borrelia burgdorferi antigenic products may be used.

Both items #0171 and #0172 have wording which implies that they are optional treatments, as they use the word, "may be administered"  or "may be used" rather than "will be administered" or "will be used", respectively. I would assume that whether or not these individual treatments are applied depends entirely on the individual patient and their needs and clinical diagnosis.

So, it seems that whether there is current infection or not, VGV-L may be one way to effectively treat chronic Lyme disease and lower inflammation due to runaway immune dysregulation. And if infection is currently present, then it looks like VGV-L will trigger a more targeted immune response towards bacteria rather than the overload that polyclonally expanded B cells can be.

One of the more fascinating sections of the patent is towards the end. The researchers give a number of examples of how their technology was applied and what the results were. Example 13 of this patent appears relevant to demonstrating how Borrelia burgdorferi activators affect tissue and about eliminating excessive B cells which cause inflammation in tissues. They did an in vitro post-mortem study of these actions in mice:

Example 13 - TLR Activators Promote CLIP-MHC HLA Association and CLIP Inhibitor Peptides Reduce an TLR Activator Promoted CLIP-MHC HLA Association

[0480] Methods

[0481] Preparation of Cells: Mice were Sacrificed by Cervical Dislocation. Spleens and lymph nodes were removed; the tissues were minced through cell strainers to create single cell suspensions; red cells were lysed using buffered ammonium chloride followed by addition of phosphate buffered saline and centrifugation to wash out the ammonium chloride; and the cells were counted using trypan blue exclusion to determine live versus dead cell discrimination and to determine the number of cells per tissue.

[0482] Treatments: The spleen or lymph node cells were treated in vitro with various stimuli (TLR activators: CpG ODN (Alexis), LPS (Sigma), Polyl:C (BD Pharmagen), Pam3Cys (Genway); IL-4 (BD Pharmagen), anti-CD40 monoclonal antibody (BD Pharmagen), both IL-4 and anti-CD40 antibody and OspA and Osp C (Genway) and the cells were cultured for the indicated time periods. The cells were grown in RPMI 1640 medium supplemented with standard supplements, including 10% fetal calf serum, gentamycin, penicillin, streptomycin, sodium pyruvate, HEPES buffer, 1-glutamine, and 2-ME as well as (where indicated) the stimuli listed above. The cells were incubated at 37° C. in an atmosphere containing 5% CO2 and approximately 92% humidity. The cells were incubated for 3, 24, and 48 hours. At each time point, the cells from that experimental time were harvested and stained for flow cytometric analysis of cell surface expression of CLIP (MHC Class II invariant peptide/IAb, Santa Cruz) by using the commercially available anti-mouse CLIP/IAb peptide, anti-mouse B220, anti-mouse CD4, anti-mouse CD8, and anti-mouse FoxP3 (all commercially available from Becton Dickinson/Pharmingen). Harvested cells were stained using standard staining procedure that called for a 1:100 dilution of Fitc-anti-mouse CLIP/IAb or isotype control. Following staining on ice for 25 minutes, cells were washed with PBS/FCS and resuspended in 100 microliters and added to staining tubes containing 400 microliters of PBS. Samples were acquired and analyzed on a Coulter Excel Flow Cytometer. The data were analyzed using FloJo software.

[0483] Results

[0484] B cell death, including total B cell death and % CLIP positive B cell death in cells treated with a TLR activator (CpG ODN) alone or in combination with MKN3 in the presence or absence of CLIP was assessed. The results are shown in FIG. 12. FIG. 12 is a line graph having a double Y axis, on one side depicting % total B cell death (diamonds, representing CpG ODN alone and squares representing CpG ODN+MKN3) and on the other side depicting % CLIP+ B cell death (triangles, representing CpG ODN and CLIP alone and Xs representing CpG ODN+MKN3 and CLIP). The data reveal that CpG ODN cause an initial increase in B cell death which after 72 hours appears to level off. The CpG ODN+MKN3 data demonstrate that MKN3 is capable of preventing the increase in B cell death.

[0485] Changes in CLIP positive B cells in spleen versus lymph nodes were also assessed. FIG. 13 is a line graph having a double Y axis, on one side depicting % CLIP+ B cell numbers in spleen (light gray square with solid lines representing CpG ODN alone and dark gray square with solid lines representing CpG ODN+MKN3) and on the other side depicting % CLIP+ B cell numbers in lymph nodes (diamonds with dashed lines representing CpG ODN alone and light gray square with dashed lines representing CpG ODN+MKN3). In both spleen and lymph nodes the addition of the peptide to the cells with CpG ODN resulted in less CLIP positive B cells.

[0486] CLIP positive B6.129 cultured B cells (H-2b haplotype) and H2M-/- (from C3H HeJ mice) cultured B cells were also examined in the presence or absence of treatment with a number of different TLR activators. The data is shown in FIGS. 14A and 14B. As shown in the Figures, several TLR activators were able to induce levels of CLIP+ B cells.

Just so it's clear, this isn't the treatment a patient would receive - Dr. Newell Rogers and her colleagues won't be breaking your neck and removing your tissues if you sign up for a clinical trial, okay?

This is an example of an experiment they did to show that VGV-L technology is effective in reducing the number of ineffective B cells which cause inflammation. The end result measured this change, and also measured the end of the sordid relationship between TLR-promoted CLIP MHC-HLA association in the immune system.

[Edited Apr. 3, 2012: Removed mention of CLIP positive cells - these cells need to be removed not added. ]

Now time for a brief lesson in immunology, based on what normally happens in immune response:


Terminology:
MHC = major histocompatibility complex; key components of T cell immunity. Think of them as immune response genes.
HLA = human leukocyte antigen (think of earlier discussions on this blog about HLA-DR4 and HLA-DR11, and different alleles which respond to infection differently)

So the story goes, B cells express MHC class II. Once antigen has been bound on the antigen receptor on the B cell, the antigen and its receptor are sucked into an endosomal compartment inside the B cell. Then the endsomal compartment fuses with another compartment, the lysosome.

Antigens are broken down into smaller pieces inside the lysosome and then loaded onto the MHC class II component, then the MHC is transported to the B cell surface where the B cell displays the antigen to a CD4+ T cell. This T cell is also known as a helper cell, of which there are two types - Th1 and Th2.

Susceptibility or resistance to many diseases appears to be determined by the genes encoding Major Histocompatibilty Complex (MHC) molecules. Often referred to as immune response genes (or IR genes), these molecules are the key players in restricting T cell activation.

T cells, both CD8 and CD4 positive T cells, recognize antigens only when the antigen is presented to the T cell in association with MHC class I (expressed on all nucleated cells) or MHC class II molecules (expressed on cells that present antigens to CD4+ T cells), respectively.

To sum up:
  1. B cells express MHC class II.
  2. Different people produce different levels of allele variation in MHC locus.
  3. Because of this genetic difference, some people are more or less vulnerable to certain diseases.
  4. The B cell's expression of MHC class II  is noticed by CD4+ T cells.
  5. These CD4+ T cells are known as helper cells - of which there are two types, Th1 and Th2.
  6. CD4+ T cells are a major player in our immune systems for fighting infection.
  7. These helper cells do not kill - they activate and direct other immune cells. They are essential in B cell antibody class switching, in the activation and growth of cytotoxic T cells, and in maximizing bactericidal activity of phagocytes such as macrophages.
Look at these handy diagrams as an overview to what happens with B cells, MHC molecules, and T-cells...


Or, if your learning style is better geared towards watching videos, watch this one (warning: might be preceded by an ad, which you can mostly skip):

A simple overview of the immune system [Time: 5:56]
 



If you've gotten this far, right about now you might be asking yourself, "So what's the big deal? Why is it an issue that there are excess B cells, and how getting rid of them going to make a difference in fighting off Lyme disease if I have a chronic infection?"

Good questions. 


Obviously, you can see so far that one reason to not have certain B cells around is that they trigger autoimmune responses. No one wants that. But there are other reasons to avoid an overzealous non-specific B cell response.

Let me unwind the answer, step by step.

Google "polyclonally expanded B cells Borrelia" and tell me what you find. Or, read on and I'll tell you what I found:

Remember that study on Borrelia burgdoferi that Tunev and Barthold did, where it was noted that there was an outsized yet seemingly inadequate immune response to Borrelia burgdorferi found in lymph nodes? One with ill-formed B cells? This one: http://www.plospathogens.org/article/info%3Adoi%2F10.1371%2Fjournal.ppat.1002066 ?

Well, the phenomenon that's happening there is somewhat different from what is happening in polyclonal B cell activation in general. In polyclonal B cell activation, there can be lots of B cells which are produced which are non-specific. In this case, in Tunev and Barthold's research, a notable percentage of the B cells were Borrelia burgdorferi antigen specific - yet the cells were of low quality and inadequate to the task.

That's different than what is generally understood to be the typical polyclonal B cell activation, which is what I think is the hypothesis behind this treatment, VGV-L. In both cases, what one observes is an overwhelming number of B cells being produced.

[Edit Apr. 3. 2012: Updated correction to describe Tunev and Barthold difference in outcome of B cell activation.]

Polyclonal b cell activation has been thought to be a useful immune defense mechanism early in acute infection. What has not been investigated as much is how it might be a damaging process in chronic infection and immune dysregulation.

And there has been some argument in the microbiological world about whether polyclonally expanded B cell generation is essentially good or evil - the pros of cons of which are discussed in detail in this paper, "Polyclonal B cell activation in infections: infectious agents’ devilry or defense mechanism of the host?"

It's important to settle this argument because dysregulated and mis-targeted B cell antibody responses could result in autoimmunity, whereas impaired antibody responses during an actual infection could result in an immune deficiency.

Either way, over time it has become clearer that the production of these B cells relates to the appearance of an IgM response, and the relevance of the presence of an IgM response - particularly a prolonged IgM response - has also become a subject of heated discussion. See: "IgM in microbial infections: Taken for granted?"

But I digress...

This early paper from 1992 which is about Borrelia's relationship to polyclonal B cell activation, "Evidence for B-Lymphocyte Mitogen Activity in Borrelia burgdorferi-Infected Mice" (full text), has this to say in its abstract:
"We have used the murine model for Lyme disease described by Barthold et al. (S. W. Barthold, D. S. Beck, G. M. Hansen, G. A. Terwilliger, and K. D. Moody, J. Infect. Dis. 162:133-138, 1990) to determine whether the B. burgdorferi B-cell mitogen is expressed during active infection.

To correlate arthritic changes with immune events, we have studied two strains of mice injected with B. burgdorferi; one of them, C3H/HeJ, developed severe disease, and the other, BALB/c, developed only mild disease. C3H/HeJ mice displayed a persistent 10-fold increase in circulating immunoglobulin G (IgG) levels, a 2-fold increase in IgM levels, and a 15-fold increase in peripheral lymph node B-cell numbers, providing evidence of mitogenic activity. Infected BALB/c mice also had evidence for mitogen activity, since the IgG level in serum increased three- to fourfold. 
The bulk of the increase in circulating IgG levels was not directed against B. burgdorferi antigens, supporting the occurrence of polyclonal B-cell activation. Analysis of IgG isotpes pointed out a contrast between C3H/HeJ and BALB/c mice in that levels of all isotypes were elevated somewhat in both strains of infected mice but IgG2a levels were much more dramatically increased in the C3H/HeJ mice (28-fold) than in the BALB/c mice (4-fold). In this study, interleukin-6 levels were found to be persistently elevated in the serum of infected C3H/IHeJ mice. Interestingly, interieukin-6 levels in serum were much lower in the infected BALB/c mice. These findings indicate that the B. burgdorferi mitogen is active in infected animals and may contribute to the inflammatory and immune response to infection."
Right from the start, you get the idea that this paper is going to tell you that the presence of these polyclonally activated B cells have a relationship to IgM and IgG levels.

This is relevant, very relevant - because it can reflect how antibodies to Borrelia burgdorferi are present and how they are picked up in serological testing like ELISA and Western Blots.

Meaningful excerpts from this paper include:
"Immunological abnormalities, including hyperactive B cells, elevated IgM levels in serum, lymphadenopathy, impaired natural killer function, and delayed development of humoral immunity, have been documented in patients with Lyme disease (11, 16, 29, 30, 32). This has suggested a possible involvement of the specific or innate host responses in the pathogenesis associated with stage 2 and 3 disease(32)."
"Because of the persistent nature of infection and the ability of the organism to gain access to the joint and other tissues (5, 15, 29), a B-cell mitogen present during infection could play a role in the pathology of Lyme disease. To support this possibility, it was important to determine whether the mitogen functioned in vivo. This paper provides evidence that a B. burgdorferi mitogen is active in vivo in infected animals.
Three lines of evidence support the conclusion that B-cell activation in vivo is polyclonal or oligoclonal in addition to being antigen specific. 
First, the level of IgG in serum in infected mice was elevated about 10- to 15-fold, with the value ranging from 10 to 15 mg/ml (Fig. 1C). In comparison, the amount of IgG specific for B. burgdorferi antigens was approximated at 0.6 mg/ml (Fig. 2)
Second, the number of B lymphocytes in peripheral lymph nodes of infected animals was increased 10- to 15-fold, with a 5-fold rise in the ratio of B to T cells (Fig. 4). The number of B cells also increased about twofold relative to the number of T cells in spleens from C3I/HeJinfected mice. 
Third, the IgG titer in the serum of infected animals to an unrelated antigen, ovalbumin, was increased 10- to 15-fold, which resembles the increase in the total IgG level (Fig. 3). 
These findings suggest that levels of autoreactive antibodies might be also expanded in infected animals, although anti-collagen antibodies were not identified. Because CD5+ B cells have been shown to produce autoreactive antibodies and are selectively increased in patients with rheumatoid arthritis (7), we determined whether they were expanded in B. burgdorferi-infected animals. No selective increase in the number of B cells of this lineage were found in C3H/HeJ animals at any stage of infection. Further studies are required to determine whether autoreactive antibodies are generated during infection."
So their initial experiment to see if there was an overwhelming B cell response provides us with evidence that yes, there is, and also - while there is a high IgG response, only a small percentage of IgG produced is B. burgdorferi specific. There was at the time no indication that autoreactive antibodies were involved.

(This process can be a precursor to autoimmunity developing - but that's later on.)

A later paper, from 1997, "Why is chronic Lyme Borreliosis chronic?"(full text), also brings up a host of issues related to TLRs, MHC class II, and the relationship between B and T cells in lymph nodes.

Doesn't it seem a little prescient?
"The question remains whether downregulation or even loss of MHC class II molecules on LCs might influence a patient's disease susceptibility. It is MHC class II molecules that bind antigenic peptide fragments, present them to CD4+ Th cells, and induce cytokine secretion and IgG secretion by B cells [55]. In vitro investingations have shown that MHC II class molecules are downregulated on antigen-presenting cells after coculture with Th cell clones in the presence of antigenic peptides of tetanus toxoid or staphylococcal superantigen, which elicit a strong HLA-DR-restricted T cell response.

Several hypotheses were suggested as the cause of this down-regulation. 
(1) Downregulation occurs when antigenic peptides catabolized in macrophages are recognized by CD+4 helper T cells, in order to control the size of a T cell clone and provide a homeostatic mechanism [55]. (2) Downregulation occurs for completion of T-B cell collaboration after antigen presentation, limiting excessive T cell help to the triggered B cells, or (3) it occurs for focusing the T cell repines to one or a few immunodominant peptides.

(4) LCs of patients with AIDS express decreased amounts of MHC class II molecules. Polyclonal B-cell activation, as seen in these patients and in patients with ACA, could cause the appearance of autoantibodies or immunocomplexes that interact with LCs and block their surface-staining characteristics [45]. (5) IL-10, originally identified as a product of Th2 cells, has a significant inhibitory influence on the antigen-presenting functions of macrophages and LCs by downregulation of MHC class II molecules. In fact, LCs pretreated with IL-10 were converted from specifically sensitizing to specifically tolerogenic antigen-presenting cells in vitro and in vivo [56]. In other studies treatment of LC cultures with IL-10 inhibited to upregulation of HLA-DR [57].

(6) Downregulation is initiated for establishment of self-tolerance. This downregulation can protect the antigen-presenting cell by inhibiting the presentation of self-antigens [58]. On the other hand, the downregulation of MHC class II antigens on LCs could result in inadequate presentation of antigens in lymph nodes, which in turn may reduce activation and proliferation of both B and T cells and the secretion of relevant cytokines. This may be what happens in CLB."
Dr. Karen Newell Rogers et al recent patent has this to say about TLRs (Toll Like Receptors) and B cells:
"Many bacteria and viruses produce substances, collectively called Toll ligands, that elicit an immediate response from an individual's immune system. These Toll ligands appear to promote inflammation by activating a wide variety of immune cells to bring them rapidly into battle against the invading pathogen. 
In most cases, these events correlate with a healthy and productive immune response to the pathogen. However, in some cases the Toll ligand binds to a Toll-like Receptor (TLR) on lymphocytes and non-specifically activates immune cells called B and T lymphocytes that would normally to respond to infectious pathogens with an exquisitely specific response. When Toll ligands activate B cells in a non-specific way, the non-specific activation is a pro-inflammatory event that may result in uncontrolled, or even auto-reactive, production of antibodies. When a B cell is activated non-specifically, we have discovered that the B cell expresses an important, small self-peptide called MHC class II invariant peptide, CLIP. In most individuals, a control cell, known as a T regulatory cell (Treg for short), has been shown, to kill the activated B cell.

During a viral or bacterial infection, non-antigen specific B cells in close proximity to an inflammatory or inciting lesion could manage to become activated in a bystander fashion. In those cases, CLIP would remain in the groove and get transported to the cell surface of the B cell. Its presence on the cell surface can be undesirable because if CLIP gets removed from the groove by a self antigen, the B cell would be in a position to present self antigens to self-reactive T cells, a process that could lead to autoreactivity and autoimmune disease. 
For some B cells this may result in death to the B cell by a nearby killer cell, perhaps a natural killer (NK) cell, unless the antigen receptor on the B cell has engaged antigen. Antigen recognition would thereby provide a survival signal for the B cell. However, if a killer cell doesn't remove the potentially autoreactive B cell and it encounters a CD4+ T cell that can recognize that antigen (most likely one that was not in the thymus) the B cell might receive additional help from a T cell specific for the antigen that now occupies the groove (antigen binding location in the MHC molecule). Alternatively, a nearby cell whose job it is to detect damaged self cells, may become activated by the self antigen-presenting B cell. Such a damage detecting cell is, for example, an effector T cell (Teff) such as a gamma delta T cell, also referred to as a γδT cell (γδ refers to the chains of its receptor). The γδT cell can then seek out other sites of inflammation (for example in the brain in MS, in the heart for autoimmune myocarditis, in the pancreas in the case of Type I Diabetes). Alternatively, the γδT cell might attempt to kill the CD4+ T cell that may respond to self antigens."
So based on all this, I think one has to consider that the complex interactions within the immune system related to B. burgdorferi infection have to be paid close attention to - and not just any persisting spirochetes themselves.

I am really interested in seeing what VGV-L - along with supportive and antibacterial treatment together - can do for chronic Lyme disease. It appears it not only prevents autoimmune responses to infection, but redirects the immune response so it can better target infection.

I do wonder, though,  how VGV-L would handle a situation where many B cells are being created and a good percentage of them are antigen specific but are of low quality - such as those mentioned in Tunev and Barthold's research.

* It may be that Lyme disease is more like HIV in that inflammation may allow or facilitate the spread of spirochetes as it encourages vlsE recombination. See: http://www.jimmunol.org/content/167/6/3383.long for one example.

Additional Resources:
Interview with Dr. Karen Newell Rogers: http://www.timeforlyme.org/TFL_newsletter_july_2011_q_a.htm
Marketwatch on VG Pre-IND submission to FDA: http://www.marketwatch.com/story/viral-genetics-submits-pre-ind-document-for-lyme-disease-drug-candidate-to-fda-2012-03-07

[Edit Record: This page was edited 2 times on April 3, 2012.]

If you've made it this far and still want to learn more about VGV-L, there are other posts on this subject on the site. Begin with this link: http://campother.blogspot.com/2012/04/notes-posted-on-vgv-l.html


4 comments:

  1. I want to add a comment here to readers that I may revise this entry. While it does outline what VGV-L is supposed to do and part of the potential process a patient might undergo if they were treated, a more concise explanation of how the immune system might be failing (polyclonal B cell activation and Treg cells) to act appropriately compared to how it would act under normal circumstances is needed here.

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  2. Also, in the Star Trek description of HIV, the cloaking aspect may not apply to Lyme disease - but the inflammation aspect definitely does.

    There is some debate if Borrelia burgdorferi can be intracelluar. In vitro studies and limited in vivo evidence points to this possibility. Mostly, Bb is an extracellular organism, so cloaking may not apply here. HIV, on the other hand, does infiltrate cells and may be hidden.

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  3. A few days after posting this and I want to point out this passage I came across in Tunev and Barthold et al paper on lymphadenopathy in Bb infection:

    source: http://www.plospathogens.org/article/info%3Adoi%2F10.1371%2Fjournal.ppat.1002066

    "Since neither the lymphadenopathy nor the B cell response were significantly different following infection of MyD88−/− mice compared to controls (Figure 7), TLR-mediated inflammatory responses can be excluded as potential triggers of this response, in contrast to apparently similar TLR-4-mediated alterations following S. typhimurium infection [17].

    From this, it is tempting to speculate that it is the expression of specific immune-subversion antigens by B. burgdorferi in the mammalian host that induce overshooting and potentially aberrant T cell independent B cell responses that are neither of sufficient high-affinity nor induce memory responses able to combat primary and repeat infections. The analysis of candidate antigens must await the development of techniques that allow us to comprehensively compare protein expression by culture-grown and tissue-adapted spirochetes within the context of specific tissue sites, such as lymph nodes.

    While the induced B cell response to B. burgdorferi is unable to clear the infection, it does provide immune protection from overt disease. This is indicated by studies in B cell- or CD40L-deficient mice that showed increased signs of tissue-inflammation and disease progression compared to controls [29], [40], [45]. Furthermore, passive transfer of immune serum from infected mice confers immune protection from infection when injected prior to pathogen challenge [26], [30]. Thus, understanding the mechanisms that induce and regulate the borrelia-specific B cell response is of importance."

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  4. Could this be of interest for you?

    Eur J Clin Invest. 2013 Feb 8. doi: 10.1111/eci.12063. [Epub ahead of print]
    Effects of CXCL13 inhibition on lymphoid follicles in models of autoimmune disease.
    Finch DK, Ettinger R, Karnell JL, Herbst R, Sleeman MA.

    http://www.ncbi.nlm.nih.gov/pubmed/23517338

    Panda

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