What is Paternal Lymphocyte Immunization (PLI)?

In Paternal Lymphocyte Immunization (PLI), white blood cells from the intended father are separated
from his blood and injected into the mother. Given that both the mother's and the father's genes are
present in pregnancy tissues, PLI (LIT) Therapy helps the mother's immune system build immunologic
tolerance to the genetically alien pregnancy tissues. If a woman has had several miscarriages or failed
IVF attempts, she may benefit from this treatment. Immunological issues are typically a cause for these
miscarriages or failures.

This therapy is used to address these shortcomings and raise the success rate. PLI Therapy was created
to assist in preparing the immune system for pregnancy so that the immune system may assist in
acclimatising the potential mother's body to foreign cells.

When is PLI (LIT) Therapy in IVF Necessary or Recommended?

PLI (LIT) Therapy in IVF is typically used following several unsuccessful IVF cycles and possible
immunologic causes of poor implantation.

A normal pregnancy would allow the foetus to grow in the mother's uterus, and the growth would
continue as an allograft that benefits from the foetus' and mother's immunological tolerance. However,
there are instances where the mother's immune system rejects the foetus. Primary RPL (Recurrent
Pregnancy Loss) aborters and Secondary RPL aborters are the two basic categories into which recurrent
pregnancy losses may be divided. The secondary RPL aborters have at least one normal pregnancy, but
the primary aborters have no history of normal pregnancy. Hormonal, Metabolic, or Uterine
abnormalities are a few of the main reasons, even if the cause may not be discovered in 50% to 60% of
instances.

Who can benefit from Paternal Lymphocyte Immunization (PLI) Therapy?

Up to 5% of couples who are of childbearing age may experience recurrent miscarriages. The women
who experience recurrent miscarriages or numerous IVF failures owing to immunological reasons, PLI
(LIT) Treatment can help them. Although additional research is required, it has been demonstrated that
PLI increases the live birth rate in women who experience recurrent miscarriage and implantation
failure.

How Does PLI Help Fertility Outcomes?

When immunological causes for unsuccessful embryo implantations are suspected, PLI (LIT) Therapy is
frequently carried out. It is thought that because the developing embryo and foetal tissues are produced
from both the mother and father's DNA, the mother's immune system mistakenly views proteins formed
from the husband's share of the genome as foreign and attacks the developing baby. Paternal
Lymphocyte Immunization (PLI) was created to make the mother's immune system ready for pregnancy
so that it can help acclimate the potential mother's body to foreign cells rather than fighting and
destroying the embryo or foetus.
By introducing paternal proteins, antigens, and cellular structures to the developing embryo or foetus in
a "friendly" manner before they may be deemed toxic and lead to the termination of early pregnancy,
PLI Therapy is expected to alleviate this detrimental reaction.

Benefits of PLI (LIT) Therapy in IVF

When a woman experiences repeated miscarriages, PLI treatment is one of the highly preferred medical
procedures incorporated to increase her chances of getting pregnant. When individuals with
immunological disorders take this treatment, the success rates are significantly greater. The benefits
listed below demonstrate why LIT treatment is one of the greatest approaches to increasing their
chances of pregnancy:

Significantly Higher Rate of Success

Patented & Researched Technology

Having No Long-term Side Effects

Single Seating Procedure

Minimum Chances of Negative Side Effects

Safe Procedure

Simple and Easy Treatment

Possible Side-Effects Resulting from PLI

There were no significant adverse effects, such as graft versus host disease, allergy, or autoimmune
issues, found in large research involving 4500 instances of Paternal Lymphocyte Immunization. The
majority of adverse effects were local in nature. A burning feeling, swelling, irritation, redness, and pain
or discomfort in the vaccinated arm, along with swelling, are just a few examples of these local yet trivial
responses. A defining feature of LIT treatment is the presence of blisters at the injection sites. Malaise, a
little temperature rise, and skin rashes are just a few examples of systemic symptoms that may appear.

What is Lymphocyte Immunization Therapy (LIT)?

Lymphocyte Immunization Therapy (LIT) is a therapeutic option for couples with idiopathic recurrent
miscarriages and unexplained infertility. It is an immunotherapy treatment aimed at improving
pregnancy outcomes in women with recurrent pregnancy loss or repeated implantation failure. LIT
works by introducing paternal antigens into a prospective mother to reduce the chances that her
immune system will reject an embryo/fetus.
Under normal circumstances, the immune system should allow for a fetus to grow even though half the
proteins of the fetus are different from the mother's since they are of paternal origin. However, in some
cases, it is possible the maternal immune system fails to recognize that the fetus is not harmful and
therefore it may "attack" the embryo.

A prior introduction of paternal factors through LIT could induce active immunological tolerance from
the maternal immune system to “acclimate” the maternal immune system to the paternal proteins of
the embryo.

How does LIT work?

More specifically, the proposed LIT mechanisms of action includes a humoral response with the
production of anti-idiotype and asymmetric-blocking antibodies preventing maternal rejection of the
fetus. This involves stimulating the maternal immune system to produce antibodies such as Anti-
paternal cytotoxic antibody (APCA), Ab2, anti-T cell receptor (TCR) idiotypic antibodies, MLR-Bf, and
progesterone-induced blocking factor (PIBF). These antibodies help prevent the maternal immune
system, particularly T and NK cells, from recognizing paternal HLA antigens by blocking these antigens.
Additionally, LIT is reported to reduce NK cell activity, downregulate the expression of maternal IL-2
receptors, shift the immune response toward Th1, improve the Th1/Th2 balance, and increase Treg
responses over Th17 responses.

LIT was originally recommended by Dr Alan E. Beer, a pioneer in the field of reproductive immunology
and although it has been shown to increase in live birth rates and decreased miscarriage rates in
numerous uncontrolled studies and case reports, it is nevertheless still considered experimental and is
not FDA or otherwise approved as an official treatment and that there is no randomized controlled data
to support its efficacy. For this reason, unfortunately, LIT is not universally available and its use varies by
country and region, often making it less accessible for patients worldwide that might need it.

Current systematic review data suggests up to a 45% increase in live-birth rate.

Efficacy data overall supports the utility of LIT although controversy does exist. There are numerous
studies that support positive impact, increase in live birth rates and decreased miscarriage rates,
although no well-done randomized controlled trial(s) exist to prove that this therapy is beneficial in
cases recurrent implantation failure and/or recurrent pregnancy loss beyond any doubt.

The most recent systematic review and meta-analysis from the American Journal of Reproductive
Immunology demonstrates that there is a 45% increase in live birth for patients doing LIT compared to
those who received placebo or no treatment (RR= 1.97,95% CI= 1.53-2.53). In addition the results of the
analysis showed:

• A trend towards benefit with paternal LIT

Studies have also shown varying degrees of effectiveness based on individual immune profiles and
underlying causes of infertility or pregnancy loss.

The treatment is usually administered in multiple sessions. The exact number of sessions and timing
depends on the individual case and protocol recommended by the reproductive immunologist. Although
usually individually tailored to meet the specific needs of each patient, a typical LIT Immunotherapy
protocol is performed by intradermal injections of isolated mononuclear cells with 15 to 30 day intervals
in one or more “priming” or “maintenance” sessions followed by one or more “booster” sessions at
specific points during pregnancy. Usually these include:

1) Confirmation of pregnancy (on a positive doubling hCG test)

2) Detection of fetal heartbeat (6-8 weeks)

3) Nuchal Translucency scan (11-14 weeks)

Less or more LIT sessions may be required based on patient clinical history and primary and pregnancy
monitoring lab test results.

Pregnancy monitoring testing of LAD, NK cells, Regulatory T-Cells (Tregs), NK cell cytotoxicity and
Th1/Th2 cytokine ratio is advisable to evaluate therapeutic efficacy of LIT and to adjust number and
frequency of LIT sessions.

The initial results of the treatment should be generally visible at 4-12 weeks. Additional sessions can be
necessary for full effect. Fertility therapy or natural attempts at conception should be considered within
the 1–3-month time frame following treatment. Of course, all individuals are different so there will be
variations from one person to the next.

2) Skin diseases (i.e. SLE, porphyria, allergies)

3) Cancer 4) Chemotherapy treatments

5) Severe: metabolic and systemic disorders

6) Abnormal platelet function (blood disorders, i.e. Hemodynamic instability, Hypofibrinogenemia,

7) Chronic Liver Pathology

8) Anti-coagulation therapy

9) Underlying Sepsis

10) Systemic use of corticosteroids within two weeks of the procedure.