NRL of Immunology

Since the beginning of 2020, NRLI offers a range of tests for evaluation of SARS-CoV-2 specific antibody and T-cell response. The proposed tests are extremely useful for evaluation of patients with primary and secondary immune deficiencies, chronic viral infections and unexplained fever, "chronic fatigue syndrome", malignancies and allergies.

Research studies performed at NRLI are related to the homeostasis and regeneration of lymphocyte subsets, the regulation of the immune response and its disorders in chronic infections, the possibilities for immunomodulation of adaptive and natural immune response. NRLI has established collaborations with the Medical Universities in Sofia, Plovdiv, the Biology Department of Sofia University, the institutes of Microbiology and Molecular Biology at the Bulgarian Academy of Sciences, etc. A long-term collaboration exists with the National Institute of Health and Medical Research of France (INSERM), the Medical Faculty of UPEC and the Department of Clinical Immunology of the University Hospital A. Mondor”, Creteil, France, as well as the Immunology Department of Tor Vergata University in Rome, Italy. The laboratory staff has co-authored over 200 scientific publications in Bulgarian and international scientific journals.

• Quantitative determination of serum (plasma) immunoglobulins (IgG, IgM, IgA)
• Immunophenotyping of blood cells by flow cytometry, basic panel
• Immunophenotyping of blood cells by flow cytometry, individualized panel
• Immunophenotyping of chronic lymphoproliferations
• IGRA tests for diagnosis of tuberculosis infection
• IGRA tests for SARS-CoV-2 cellular immune response
• Phagocytic activity by flow cytometry
• Leukocyte activation by flow cytometry
• Antigen-specific T – lymphocytes (EBV, CMV, HIV, SARS-CoV-2) by flow cytometry
• Flow cytometry test for basophilic degranulation
• T-cell functional activity by spontaneous and mitogen-induced production of IFN-gamma
• IgG anti-nuclear autoantibodies - immunoblot analysis
• IgE allergen-specific antibodies - immunoblot analysis

1. Gesheva V., Kerekov N., Nikolova K., Mihaylova N., Todorov T., Nikolova M., Tchorbanov A., Suppression of dsDNA-specific B lymphocytes reduces disease symptoms in SCID model of mouse lupus. Autoimmunity. 2014 May;47(3):162-72. (IF 2.75)
2. Kerekov N., Ivanova I., Mihaylova M., Nikolova M., Prechl J., Tchorbanov A., Built-in adjuvanticity of genetically and protein-engineered chimeric molecules for targeting of influenza A peptide epitopes. Immunol Res. 2014 Oct; 60(1):23-34. (IF 3.53)
3. Avramov T., Vetskova E., Nikolova M., Dinko Valev, Manolova A., Tafradgiiska M., Kostadinov D. Tchalacov I. Therapeutic approaches to the treatment of recurrent respiratory papillomatosis of the aerodigestive tract (a clinical study), Biotechnology & Biotechnological Equipment, 2014, 28:4, 668- 673 IF 0.38
4. I Alexiev, A Shankar, A.M.J. Wensing, D Beshkov, I Elenkov, M Stoycheva, D Nikolova, M Nikolova and W M. Switzer. Low HIV-1 transmitted drug resistance in Bulgaria against a background of high clade diversity diversity J. Antimicrob. Chemother. (2015) doi: 10.1093/jac/dkv011 (IF=5.3)
5. N. Yancheva, I. Elenkov, T. Tchervenyakova, I. Gabarska, G. Kirilov, M. Nikolova, M. Alexandrova. Deficiency of Vitamin D in HIV Infected Patients and Its Effect on Some of the Immunological Parameters. World Journal of AIDS, 2015, 5,182-188; (IF 0.80)
6. Nikolova M, Wiedemann A, Muhtarova M, Achkova D, Lacabaratz C, Lévy. Subset- and Antigen- Specific Effects of Treg on CD8+ T Cell Responses in Chronic HIV Infection.Y.PLoS Pathog. (2016) Nov 9;12(11):e1005995. doi: 10.1371/journal.ppat.1005995. eCollection 2016 (IF 7.00)
7. M. Alexandrova, E. Golkocheva-Markova, А. Timchev, N. Yancheva, I. Elenkov, I. Alexiev, P. Teoharov, T. Varleva, M. Nikolova. HCV co-infection compromising the effects of c-ART – an insight from the HIV-positive population in Bulgaria International Journal of Science and Research (IJSR), Sep 2016 , ISSN (Online): 2319-7064 (IF 0.23)
8. Alexiev, I., Shankar, A., Dimitrova, R., Gancheva, A., Kostadinova, A., Teoharov, P., Golkocheva, E., Nikolova, M., Muhtarova, M., Elenkov, I., Stoycheva, M., Nikolova, D., Varleva, T., Switzer, W.M. Origin and spread of HIV-1 in persons who inject drugs in Bulgaria (2016) Infection, Genetics and Evolution IF (2.59)
9. Vetskova, E., Aleksandrova, M., Avramov, T., Nikolova, M. Immunomodulatory effects of BCG in recurrent respiratory papillomatosis evaluated in vitro (2016) Comptes Rendus de L'Academie Bulgare des Sciences, 69 (5), pp. 645-652. (IF 0.23)
10. Nikolova, M., Wiedemann, A., Muhtarova, M., Achkova, D., Lacabaratz, C., Lévy, Y.Subset- and Antigen-Specific Effects of Treg on CD8+ T Cell Responses in Chronic HIV Infection (2016) PLoS Pathogens, 12 (11) (IF 6.18)
11. Alexiev I, Alexandrova M, Golkocheva-Markova E, Teoharov P, Gancheva A, Kostadinova A, Dimitrova R, Elenkov I, Chervenjakova T, Stoycheva M, Nikolova D, Varleva T, Nikolova M. High rate of hepatitis B and C co-infections among people living with HIV-1 in bulgaria: 2010-2014. AIDS Res Hum Retroviruses. 2016 Nov 14. [Epub ahead of print] (IF 1.95)
12. Alexiev, I., Shankar, A., Dimitrova, R., Gancheva, A., Kostadinova, A., Teoharov, P., Golkocheva, E., Nikolova, M., Muhtarova, M., Elenkov, I., Stoycheva, M., Nikolova, D., Varleva, T., Switzer, W.M. Origin and spread of HIV-1 in persons who inject drugs in Bulgaria (2016) Infection, Genetics and Evolution, 46, pp. 269-278. (IF 3.3)
13. Gokengin, D., … Nikolova, M., .. Z., Yurin, O. HIV care in Central and Eastern Europe: How close are we to the target? (2018) International Journal of Infectious Diseases, 70, pp. 121-130. (IF 4.1)
14. Marcus, …., Nikolova, M., Muhtarova, M., Kantarjiev, T.,… Johnston, L.HIV serostatus knowledge and serostatus disclosure with the most recent anal intercourse partner in a European MSM sample recruited in 13 cities: Results from the Sialon-II study. (2017) BMC Infectious Diseases, 17 (1) (IF 3.01)
15. Mirandola, M., … Nikolova, M., Muhtarova, M., Kantarjiev, T., ..Noack, P., Peeling, R., Johnston, L. Socio-demographic Characteristics, Sexual and Test-Seeking Behaviours Amongst Men Who have Sex with Both Men and Women: Results from a Bio-behavioural Survey in 13 European Cities (2017) AIDS and Behavior, 21 (10), pp. 3013-3025. (IF 3.89)
16. Amicosante, M., …., Nikolova, M., … Fuentes-Alcala, Z.Current use and acceptability of novel diagnostic tests for active tuberculosis: A worldwide survey [Uso atual e aceitabilidade de novos testes diagnósticos para tuberculose ativa: Um inquérito mundial](2017) Jornal Brasileiro de Pneumologia, 43 (5), pp. 380-392. (IF 2.6)
17. Yancheva N , Strashimirov D , Hrischev V , Tchervenyakova T, Nikolova M , Aleksiev I Three cases of non-Hodgkin's lymphoma in HIV-infected Bulgarian patients. Infez Med. 2018 Jun 1;26 (2):155-159.
18. Ivanova, I.I., Mihaylova, N.M., Manoylov, I.K., Makatsori, D., Lolov, S., Nikolova, M.H., Mamalaki, A., Prechl, J., Tchorbanov, A.I. Targeting of Influenza Viral Epitopes to Antigen-Presenting Cells by Genetically Engineered Chimeric Molecules in a Humanized NOD SCID Gamma Transfer Model (2018) Human Gene Therapy, 29 (9), pp. 1056-1070.
19. Николов Г.С., Тодорова Я.Д., Николова М.Х., Емилова Р.Г.,Христова Д.М., Костова-Шахид П.Й. , Петрунов Б.Н Субпопуляции Т-регуляторных клеток у пациентов с IGE- обусловленной аллергией журнал микробиологии, эпидемиологии и иммунобиологии. 2019; (6) DOI: https://doi.org/10.36233/ 0372-9311-2019-6-65-71
20. R Emilova , V Manolov, Y Todorova , N Yancheva , I Alexiev , M Nikolova Elevated Labile Iron Levels in CD4 and CD8 T Cells From HIV Positive Individuals With Undetectable Viral Load AIDS Research and Human Retroviruses DOI: 10.1089/AID.2020.0010 (IF 1.823)
21. I Alexiev, E Golkocheva-Markova, A Kostadinova…. Maria Nikolova . The prevalence of hepatitis B and C co-infections among people with HIV-1 in Bulgaria: 2010-2015 Future Virology Vol. 14, No. 12 Short Communication Published Online:30 Jan 2020 https://doi.org/10.2217/fvl-2019-0092 (IF: 1.83)
22. M. Nikolova, Y. Todorova, R. Emilova et al. Induction of humoral and cellular immune responses to COVID‐19 mRNA and vector vaccines: A prospective cohortstudy in Bulgarian healthcare workers. J Med Virol. 2022;1–11. IF 2.33
23. Y. Todorova, R Emilova, V Milanov, E Bachijska J Atanasova, A Bajkova, M Nikolova Eicosanoid and cytokine levels differentiate between stages of MTB infection. 2022 Folia Medica, vol. 65, no. 3, pp. 399-406. https://doi.org/10.3897/folmed.65.e80599 (Q4, IF 0.54)
24. R Emilova, Y Todorova, M Aleksova, I Alexiev, L Grigorova, R Dimitrova, N Yancheva, M Nikolova. Reactive oxygen species (ROS) features on t-cell subpopulations in people living with HIV. HIV Glasgow, 23–26 October 2022, Glasgow, UK / Virtual (wiley.com) JIAS 25, IssueS6 Supplement: Q1, IF 5.39
25. Elitsa Golkocheva-Markova, Ani Kevorkyan, Ralitsa Raycheva, Chiydem Ismailova, Viliana Yoncheva, Tencho Tenev, Radoslava Emilova, Lyubomira Grigorova, Ivan Baltadzhiev, Radka Komitova. Assessment of hepatitis E seropositivity among HIV-infected patients in Bulgaria. The Brazilian Journal of Infectious Diseases, 26, Issue 1,2022, 102329. Q3, IF 3.257
26. Lazova, S.; Dimitrova, Y.; Hristova, D.; Tzotcheva, I.; Velikova, T. Cellular, Antibody and Cytokine Pathways in Children with Acute SARS‐CoV‐2 Infection and MIS‐C—Can We Match the Puzzle? Antibodies 2022, 11, 25. Q2 IF 1.67
27. Nadya Ivanova-Aleksandrova, Heliana Dundarova, Boyko Neov, Radoslava Emilova, Irina Georgieva, Rayna Antova, Krasimir Kirov, Jiri Pikula, Kateřina Zukalová & Jan Zukal. Ectoparasites of Cave- Dwelling Bat Species in Bulgaria. 2022. Proceedings of the Zoological Society, 1-6. Q3, IS 0.71
28. T. Bolyarova-Konova, L. Stefanov, Z. Kolarov, R. Grozdanova, and M. Nikolova, “Anti-cyclic Citrullinated Peptide Antibody and Rheumatoid Factor and the Relationship between Periodontitis and Rheumatoid Arthritis”, C. R. Acad. Bulg. Sci., vol. 75, no. 3, pp. 451–457, Mar. 2022. , IF 0.33
29. Eleonora Kaneva, Georgi Nikolov, Yana Kandova, Bogdan Petrunov. A seroepidemiological investigation of toxocariasis in forestry workers in Bulgaria. Comptes rendus de l’Acad´emie bulgare des Sciences, 2022; Tome 75, No 5, 686-693. Q3, IF 0.33
30. I Rainova, R Harizanov, I Kaftandjiev, N Tsvetkova, R Enikova, M Videnova, E Kaneva and Y Todorova. Prevalence of Toxoplasma gondii among different groups of patients in Bulgaria and algorithm for diagnosis of toxoplasmosis, applied in the National Reference Laboratory for Diagnosis of Parasitic Diseases, Bulgaria. World Journal of Advanced Research and Reviews, 2022, 14(03), 116– 123, eISSN: 2581-9615
31. Emilova, R., Todorova, Y., Aleksova, M., Dimitrova, R., Alexiev, I., Grigorova, L., Yancheva, N., & Nikolova, M. (2022). Determination of intracellular reactive oxygen species in T-cell subsets of HIV+ patients on continuous cART. Problems of Infectious and Parasitic Diseases, 50(1), 5–11. Q4
32. Георги Николов. Алергенни протеинови семейства. Алергии Хиперсензитивност Астма, 2022, том 18, № 2: 44-53.
33. M Aleksova, Y Todorova, R Emilova, M Baymakova, N Yancheva, M Nikolova. Pre-existing immunity to beta-coronaviruses HKU1 and OC43 may affect susceptibility to SARS-CoV-2 infection Acta Microbiologica Bulgarica. 38 / 4 (2022), 294 – 300.
34. Ngoc, K., Trifonova, I., Nikolova, M., Emilova, R., Todorova, Y., Gladnishka, T., Christova I., 2022. Association between Serum Concentrations of IL-6 and IL-10 and COVID-19 Severity. Acta Microbiologica Bulgarica, vol. 38, no. 4, pp. 289-93. (Q4, IF20220.17)
35. Trifonova, I., Ngoc, K., Nikolova, M., Emilova, R., Todorova, Y., Gladnishka, T., Christova, I., 2023. Patterns of cytokine and chemokine expression in peripheral blood of patients with COVID-19 associated with disease severity. International Journal of Immunopathology and Pharmacology, vol. 37, pp. 1–12. Doi. 10.1177/03946320231163681 (Q2, IF 3.22)
36. Aleksova, M., Todorova, Y., Emilova, R., Baymakova, M., Yancheva, N., Andonova, R., Zasheva, A., Grifoni, A., Weiskopf, D., Sette, A., Nikolova, M., 2023. Virus-Specific Stem Cell Memory CD8+ T Cells May Indicate a Long-Term Protection against Evolving SARS-CoV-2. Diagnostics, vol. 13, 1280. https://doi.org/10.3390/diagnostics 13071280. (Q2, IF 3.71)
37. Todorova, Y., Emilova, R., Koleva, V., Ivanov, I., Stoikov, I., Nikolova, M., 2023. Expression of membrane-bound β-Klotho on peripheral blood CD4+ and CD8+ T lymphocytes of healthy subjects. Biotechnology & Biotechnological Equipment, vol. 37, no. 1, 2199887, DOI: 10.1080/13102818.2023.2199887 (Q3, IF2023 1.63)
38. Vangelov, D., Aleksova, M., Todorova, Y., Emilova, R., Kapincheva, N., Yancheva, N., Koleva, V., Nikolova, M., 2023. Immune Response to SARS-COV-2 in Patients with Chronic HIV Infection. Probl Infect Parasit Dis, vol. 51, no. 1, pp. 5–11. (Q4)
39. Alexiev, I., Shankar, A., Pan, Y., Grigorova, L., Partsuneva, A., Dimitrova, R., Gancheva, A., Kostadinova, A., Elenkov, I., Yancheva, N., Grozdeva, R., Strashimirov, D., Stoycheva, M., Baltadzhiev, I., Doichinova, T., Pekova, L., Kosmidis, M., Emilova, R., Nikolova, M., Switzer, W.M., 2023. Transmitted HIV Drug Resistance in Bulgaria Occurs in Clusters of Individuals from Different Transmission Groups and Various Subtypes (2012–2020). Viruses, vol. 15, 941. https://doi.org/10.3390/v15040941 (Q1, IF20235.71)
40. Todorova, Y., Emilova, R., Milanov, V., Bachiyska, E., Atanasova, Y., Baikova, A., Nikolova, M., 2023. Eicosanoid and cytokine levels differentiate between stages of MTB infection. Folia Medica, vol. 65, no. 3, pp. 399-406. https://doi.org/10.3897/folmed.65.e80599 (Q4, IF20230.54)
41. Manolov, V., Georgiev, O., Vasilev, V., Emilova, R., Petrova, I., Hadjidekova, S., Angov, G., Kunchev, T., Tzatchev, K., Traykov, L. and Pencheva, V. 2023. Iron Metabolism Dysregulation and Atherosclerotic Changes in Obstructive Sleep Apnoea, Proceedings of the Bulgarian Academy of Sciences. Sofia, Bulgaria, 76(10), pp. 1625–1632. doi: 10.7546/CRABS.2023.10.17. (Q3, IF2023 0.38)
42. Nikola Ralchev Ralchev, Nikola Kerekov, Nikolina Mihaylova, Mariann Kremlitzka, Diana Hristova, Julian Dzhorev, Anna Erdei, Andrey Ivanov Tchorbanov, Targeted suppression of Dpt-specifik B cells in humanized Rag2-yc-mouse model of HDM allergy,Scandinavian Jurnal of Immunology, (Q3, IF 3.889)