2) When SARS-COV-2 enters the body, many components of the immune system, recognize it as foreign and mount a response to eliminate it.
3) For laymen, it is not always easy to "navigate" among all the abbreviations used. In this thread, we will try to offer a quick overview of some of the key elements of the immune system and their differences.
Antibodies are proteins that are part of the immune system's response to antigens. These Y-shaped molecules are produced by specialized white blood cells called B cell
5) NAbs stands for neutralizing antibodies. NAbs are particularly important because they can block the ability of the pathogen to infect host cells or cause harm. They do this by preventing the pathogen from binding to its target receptors on host cells,
6) Immunoglobulins refer to a broader group of proteins that include antibodies, as well as other related proteins, such as cytokines and chemokines. They are classified into different classes and subclasses based on their structure and function, such as IgA, IgG, IgM ...
7) ๐ฟ๐๐๐๐๐ง๐๐ฃ๐๐ ๐๐ฃ๐ฉ๐๐๐ค๐๐๐๐จ ๐๐ฃ๐ฉ๐-๐, ๐๐ฃ๐ฉ๐-๐, ๐๐ฃ๐ฉ๐-๐๐ฝ๐ฟ
These terms refer to different types of antibodies that target specific components, spike protein (S), nucleocapsid protein (N), and receptor-binding domain (RBD).
8) To put it simply ๐, we can therefore have, anti-S NAbs or anti-N NAbs but also anti-S IgG or anti-RBD IgM.
B cells are primarily involved in producing antibodies to recognize and neutralize antigens, while T cells have diverse functions, including coordinating immune responses, killing infected cells, and regulating immune reactions.
11) There are several types of T cells. Helper T cells play a crucial role in coordinating the immune response by activating other immune cells, such as B cells and cytotoxic T cells. Cytotoxic T cells directly attack and kill cells that have been infected with viruses.
12) Regulatory T cells help to regulate and suppress immune responses to prevent excessive inflammation and autoimmune reactions.
Among these T cells, two of them, play a key role against SARS-COV-2, CD4 and CD8 T cell
CD4 T cells, also known as helper T cells have a central role in coordinating immune responses. CD4 T cells recognize antigens presented by antigen-presenting cells, such as macrophages and dendritic cells. Once activated..
14) ...CD4 T cells release chemical signals called cytokines that help to activate other immune cells, such as B cells and cytotoxic T cells.
CD8 T cells, also known as cytotoxic T cells are primarily responsible for recognizing and killing infected cells or other abnormal cells.
15) We would like to end this thread, with a very good study which summarizes the action of the immune system including others immune cells.
Thanks for reading ๐
2) This study describes the emergence of the SARS-CoV-2 Omicron subvariant JN.1 in Tamil Nadu, India between November and December 2023. JN.1 rapidly replaced the previously dominant XBB variant.
3) 66 JN.1 positive samples underwent whole genome sequencing. The majority of patients were middle-aged, with equal male/female representation. Over 50% had diabetes and 21% had hypertension
2) The study analyzed data from household surveys and serological testing of over 5,800 individuals from 2,514 households in Utah from January to April 2021.
Around 12.8% of individuals showed serological evidence of prior SARS-CoV-2 infection, and 17.4% of households ...
3) ...had at least one positive individual.
A mathematical model was developed to estimate household transmission dynamics while accounting for variability, age/size heterogeneity, and test accuracy.
2) The paper analyzes aggregated foot traffic data from mobile devices to measure mobility and contact patterns across different place categories (restaurants, retail, etc.) in New York City neighborhoods during the COVID-19 pandemic in 2020.
3) It finds distinct mobility networks and indoor contact patterns (crowdedness, dwell time) vary across place categories and neighborhoods, driven by the local distribution of points of interest and human activities.
2) SARS-CoV-2 has undergone two major evolutionary jumps - from pre-Omicron variants to Omicron BA.1, and from XBB variants to BA.2.86/JN.1. These resulted in increased genetic divergence.
3) Variants like BA.1, XBB.1.5, BQ.1.1, and JN.1 displayed high relative growth advantages (116%, 80%, 71%, 93% respectively) allowing them to outcompete other co-circulating variants.
2) The study investigated the persistence of SARS-CoV-2 in tissues of patients who had recovered from mild COVID-19. Samples were collected from various tissues at 1 month, 2 months, and 4 months post-infection.
3) Viral RNA was detected in tissues like the liver, kidney, stomach, intestine, brain, blood vessels, lung, breast, skin, and thyroid across the timepoints, with detection rates gradually decreasing over time.
2) The study aimed to understand how repeated vaccination with the ancestral SARS-CoV-2 mRNA vaccine induces antibodies that can neutralize Omicron variants, which have mutations that allow immune escape.
3) They analyzed blood samples from 41 individuals who received three doses of the BNT162b2 mRNA vaccine. Samples were collected at various time points to track the immune response.