Immunity: to help or not to interfere?

Immunity: to help or not to interfere?

There is a lot of speculation on the topic of immunology today. Even at a dentist’s reception, patients often ask: «What should I take to improve immunity?»

At the dental faculties of different universities immunology as a separate discipline is not studied. Therefore, it will be very useful to talk with an immunologist about what dentists should know of immunity, when and what drugs to prescribe in order to observe the main principle of medicine — do no harm.

Victor Litus, MD, Professor, Head of the Department of Clinical and Laboratory Immunology and Allergology of the Shupyk National Medical Academy of Postgraduate Education, leading physician-allergist of the EURODERM clinic, believes that drugs cannot be prescribed without a detailed examination of the state of the patient’s immune system. After all, immunity is a complex self-regulating system, which is not always necessary to intervene, despite the patient’s demands.

Natalia Yunakova, Ph.D., Dentist «Myroslava Drohomyretska’s Clinic of Aesthetic Dentistry», assistant professor, Dentistry Department, Shupyk National Medical Academy of postgraduate education on behalf of H-Clinic asked Viktor Litus questions of interest to dentists.

h.: Victor, explain to us, how we can understand that the human immune system can not cope and needs help?

V. L.: Immunity is a system that is constantly learning, improving. From the very birth of a person, it develops algorithms for responses to certain substances, irritants or changes in the body. The older the person, the worse the immune system learns — it grows old, begins to use the already developed algorithms.

Of course, when you carefully take a patient’s history, you notice that, for example, the patient is very often sick, the underlying disease gives frequent relapses, there are constant complaints of rapid fatigue and loss of concentration. In this case, you must necessarily direct him for consultation to general practitioner. Doctors should always remember that the patient should be examined in a comprehensive manner. We must be to some extent psychologists to clearly understand and differentiate the patient’s condition.

Immunologists often hear patients’ complaints simply for life, the vital circumstances with which they relate the deterioration of health in general. This is not an occasion for us to prescribe medication. Indication for the intervention and treatment is the immunogram and the clinical manifestations of a particular process.

h.: In what cases is it necessary to prescribe an immunological examination?

V. L.: Immunological examination is used in various fields of medicine, many doctors cooperate with immunologists. Dentists — less, but they are no exception. Immunological studies are necessary to determine the state of the immune system when the patient is examined. Today, thanks to research at the molecular level, we get more reliable diagnostic information related to the evaluation of the development of inflammatory and autoimmune processes. This, in turn, makes it possible to improve the effectiveness of treatment. On the basis of these data, individual treatment can be planned, a personal approach to each patient can be implemented. Immunological examination is necessary in the following cases: if the infectious pathology is repeated after a certain period of time; the infectious disease is treated for a long time, the conventional methods of treatment are ineffective, an allergic reaction occurs, which was not previously observed; before surgery; if the postoperative period is long and with complications.

h.: Can a dentist influence the immunity in any way?

V. L.: The dentist can correct the so-called «local» functional disorders of the immune system in the oral cavity. To do this, you can use drugs specifically designed for resorption in the oral cavity. A dentist can also advocate and explain the social importance of vaccination, which prevents the spread of epidemics.

h.: Viktor, can a dentist prescribe immunotropic drugs? If so, in which cases and on what grounds?

V. L.: Yes, you can, in particular, in case of herpetic infection, with frequent recurrences of candidal infection in the oral cavity. Due to it, not only the effectiveness of etiotropic therapy will increase, but also the functional activity of the immune system. Of course, if the dentist has any doubts about the choice of the drug, it is necessary to consult with clinical immunologists.

Victor Litus, MD, Professor

h.: One of the most common questions for dentists: is there a difference between immunocorrector and immunomodulator. Which term is more correct?

V. L.: I believe that it is difficult to understand without basic knowledge in the field of immunology, but I’ll try to explain. There is no single generally accepted classification of immunotropic drugs. Drugs that affect the immune system are combined into one large group of immunomodulators. They are divided into immunostimulants, immunosuppressants and immunocorrectors.

The term «modulation» means a change in the state of the immune system in any direction. Depending on the nature of these changes, the immunomodulator can be attributed either to stimulants, or to antidepressants, or to correctors. So, immunomodulators include drugs with direct immunotropic activity, which in therapeutic doses change the functions of the immune system.

The group of immunocorrectors includes pharmacological immunotropic drugs that normalize a specific disorder in the immune system: various components of the T-cell link of immunity, humoral immunity, phagocytosis or complement. In other words, they reduce unnecessarily high rates and raise low ones. Therefore, immunocorrectors are 100% only those drugs that are used in substitution immunotherapy to compensate for the lack of certain substances.

h.: Tell, please, about adaptogens, what is the difference from immunomodulators?

V. L.: Adaptogens are medicines of predominantly plant origin that have a general tonic effect on the functions of the central nervous system, endocrine regulation, metabolic processes, enhance the biochemical and functional adaptation of the organism to adverse effects and increase its resistance to these factors.

Adaptogens prevent depletion of the pituitary-adrenal system during stress. In general, they produce a mild stimulating effect, increasing physical and mental performance, reducing fatigue, reducing the symptoms of asthenia and impaired appetite.

h.: In what cases should adaptogens be recommended, and in what — immunomodulators?

V. L.: The main target of immunomodulators is functional disorders of the immune system, manifested in the form of frequent relapses of infectious and inflammatory diseases of all localizations and any etiology that are not amenable to treatment. There are four main principles of the use of immunomodulators.
First, they can be prescribed in a complex therapy together with antibiotics, antifungal, antiprotozoal or antiviral agents.

Secondly, immunomodulators affecting the production of endogenous interferon can be used to prevent or treat viral infections.

Thirdly, immunomodulators acting on the phagocytic link of immunity can be assigned to patients with both detected and not identified by laboratory tests of immune status disorders. That is, the clinical presentation may be the basis for prescribing the drug.

And the fourth principle — immunomodulators can be used as a monotherapy in the conduct of immunorehabilitation measures, in particular, in case of incomplete recovery after an acute infectious disease.

Thus, a decrease in any immunity parameter revealed in an immunodiagnostic research of a practically healthy person is not a reason to prescribe immunomodulatory therapy for him.

Adaptogens, in contrast, are prescribed, first of all, to improve the working capacity of healthy people, as a means of preventing diseases of infectious and non-infectious genesis, as well as in the period of convalescence, that is, as a general restorative.

h.: Viktor, prescribing a medicine, how can we take into account the patient’s individual sensitivity to a particular drug?

V. L.: Doing a laboratory tests of the sensitivity of the patient’s cells to immunotropic drugs is not always justified. In vitro, cells do not always react to drugs in the same way as they do in the whole body. The implementation of the expected effect of the immunomodulator depends on the phase of the inflammatory process and the state of activity of the target cells of the immunomodulator. The only magic immunomodulator that would solve all the patient’s problems does not exist.

Victor Litus, MD, Professor and Natalia Yunakova, Ph.D., dentist

h.: What immunogram indices should the dentists pay attention to?

V. L.: All immunogram indices are compared with the reference values obtained from the laboratory, taking into account the methods used for the research.

To assess local immunity, attention should be paid to the level of lysozyme as a nonspecific protective factor and the concentration of secretory IgA. During the immunological examination of peripheral blood, the state of T and B systems is assessed, namely: the content of T-lymphocytes (CD3 +) and their subpopulations; T-helpers (CD4 +), T-killers (CD16 +) and T-suppressors (CD8 +), immunoregulatory index — the ratio of T-helpers and T-suppressors; the number of B-lymphocytes (CD22 +), the level of circulating immune complexes.

It is also necessary to investigate the state of specific protective factors — the serum antibodies to parodontopathogenic bacteria: Actinobacillus actinomycetem comitans, Porphyromonas gingivalis, Bacteroides forsythus, Prevotella intermedia, Prevotella melanogenica, Peptostreptococcus, Fusobacterium nucleatum, Actimomycetus viscosus, Veillonella parvula.

Pathogenic microorganisms of oral biofilm and periodontal pockets cause sensitization of periodontal tissues. I am sure that the importance of microbial biofilm in the development of periodontal tissue diseases is well known to you. During these processes, there is an increase in tissue alteration, which can lead to the formation of tissue autoantibodies. The immune system reacts on them differently. In some cases, a protective immune response develops, which persists until the functional state of T and B lymphocytes is impaired. In other cases, as T-suppressors are depleted as a result of chronic exposure to autoantigens, the immune response to antigens is activated, which causes clinical symptoms of the disease.

For a humoral immune response, lymphocytes are responsible. Some of them, upon first contact with the antigen, are transformed into plasma cells and begin to produce immunoglobulins (Ig) specific for this antigen. A dentist should be guided in the meaning and indices of three classes of immunoglobulins, namely IgG, IgM, SIgA.

IgG activates the complement system and binds to certain antigens of the cell surface, resulting in these cells becoming more accessible to phagocytosis.

IgM is able to neutralize foreign particles, cause agglutination and lysis of cells.

SIgA slows the attachment of bacteria to the epithelium of the oral cavity and prevents the penetration of microorganisms into tissues.

h.: In recent years, in dental practice, patients with xerostomia are becoming more common. Tell us about the importance of saliva from the immunological point of view.

V. L.: The main humoral factor of local anti-infectious resistance of the oral mucosa is IgA-antibodies, in particular secretory (SIgA). The sources of SIgA saliva are plasma cells of small and large salivary glands and the mucous membrane of the oral cavity proper. The biological role of SIgA is diverse. SIgA inhibits the binding of microorganisms to the surface of the epithelial cells of the oral mucosa, preventing their penetration deep into the tissues. It also inhibits the attachment of fungi and viruses to the surface of the epithelium. SIgA saliva can alter the metabolism of bacteria, limit the formation of colonies, reduce the virulence of infectious agents. Violation of the barrier function of SIgA can cause many allergic diseases, the development of cellular immune reactions with damage to the mucous membrane.

SIgA saliva, being the main component of the «first line of defense», is also important in regulating the normal microflora of the oral cavity, its dispersal and entry into tissues. Insufficiency of SIgA saliva can lead to disruption of the ratio between the microflora of the oral cavity, especially its conditionally pathogenic forms, and the macroorganism. This manifests itself in the form of an increase in the number of microorganisms, the intensification of their aggressive properties, and the appearance of forms that rarely or not at all occur in healthy people.

The amount of IgG and especially IgM in saliva is insignificant, but in the gingival fluid they together with serum IgA represent the whole mass of immunoglobulins, corresponding to approximately the same concentration in serum.

A large amount of IgG, IgM, complement, neutrophils of leukocytes in the tooth-gingival sulcus forms a firm protection from the invasion of microorganisms in this area. Any discord in this protection system contributes to possible quantitative and qualitative changes in microbial biofilm followed by the development of inflammatory-destructive processes in periodontal tissues.

h.: Viktor, at last, what advice could you give to dentists who are more closely interested in immunological processes in the body? Where can they find information to navigate in such a complex and interesting science as immunology?

V. L.: Clinical immunology is studied throughout life, reading articles in peer-reviewed journals with impact factor. Basically, these are English-language editions. Attend conferences where we can ask each other questions. One of the fundamental books is «Oral microbiology and immunilogy» Richard J.Lamont, Robet A.Burne, Marilyn S.Lantz, Donald J.LeBlanc, published in 2016. I think for those who are interested, it will serve as a good start.

I will be happy if my answers are useful to readers. Immunology is a complex science, so we are always close. You send patients to us for advice, and we also do not forget about dentists. Complex approach and patient’s health is the main thing.